Reviews in Fish Biology and Fisheries (2004) 14: 207–237
Springer 2005
Bycatch quotas in the Gulf of Mexico shrimp trawl fishery: can they work? Sandra L. Diamond Department of Biology, Texas Tech University, Lubbock, TX 79409-3131, USA (Phone:+1-806+742-1999; Fax:+1-806-742-2963; E-mail:
[email protected] Accepted 26 October 2004
Contents Abstract Introduction History of US bycatch programs GOM shrimp trawl fishery Bycatch in the GOM shrimp trawl fishery Case study: 1. The New Zealand squid fishery and Hooker’s sea lions Case study: 2. Pacific halibut in the Alaska groundfish trawl fisheries Case study: 3. Pacific halibut in the Canadian groundfish trawl fishery Case study: 4. New Zealand multi-species fisheries Discussion Acknowledgements References
page
207 208 209 210 211 216 218 221 222 223 227 227
Key words: bycatch, bycatch quotas, bycatch reduction, fisheries management, groundfish fisheries, Gulf of Mexico, multi-species fisheries, red snapper, shrimp trawl fisheries Abstract Bycatch of unwanted, prohibited, or protected species is a problem in most commercial fisheries. Trawl fisheries are particularly prone to bycatch problems because trawls are not species-selective. In this paper, I review the history of finfish bycatch research in the Gulf of Mexico shrimp trawl fishery and explore the use of quotas to reduce finfish bycatch by examining four fisheries that currently use bycatch quotas: (1) the arrow squid trawl fishery of New Zealand, which uses fleet bycatch quotas for sea lion bycatch, (2) the Alaskan groundfish trawl fisheries, which use fleet quotas under a ‘‘vessel incentive program’’ for prohibited species, (3) the groundfish trawl fishery of British Columbia, Canada which uses individual vessel bycatch quotas for prohibited species, and (4) the multi-species trawl fisheries of New Zealand, which use catch balancing, or individual transferable quotas, for most commercially landed species. Based on the bycatch quota experiences in these fisheries, elements of successful bycatch quota programs include: (1) individual accountability, in the form of individual or cooperative bycatch quotas, rather than fleet quotas, (2) 100% observer coverage, (3) relatively small, manageable fleets, (4) limited landing ports that can be easily monitored, particularly if observer coverage is incomplete, (5) reliable enforcement, (6) penalties that are true disincentives, and (7) some flexibility in the system for fishermen to have alternatives to manage their bycatch. The Gulf of Mexico shrimp trawl fishery, with an estimated 20,000 licensed boats, is currently too large for individual bycatch quotas to be practical, although individual or cooperative bycatch quotas would be excellent strategies for reducing the bycatch of a smaller fleet. Mobile closed areas might be beneficial for reducing the bycatch of particular species, but these shortterm closures would require real-time monitoring of bycatch rates and vessel monitoring systems on all vessels. However, under any management regime, incentives and/or rigorously enforced disincentives are the key to successful bycatch reduction.
208 Introduction Bycatch in commercial fisheries involves issues of economic, ethical, and ecological importance; thus, bycatch and how it is managed is attracting increasing attention from fishery managers, commercial and recreational fishermen, environmental groups, and the general public. Bycatch can have significant economic impacts on directed fisheries because the catch quotas allotted to directed fisheries are often reduced to account for the fish caught as bycatch in other fisheries. In terms of ethics, many people feel that because most individuals caught as bycatch are discarded overboard, that bycatch fish are ‘‘wasted’’, or killed without providing some direct benefit to humans. As fishery resources have declined, society has demanded more efficient use of resources, so these issues of allocation and waste have increased in significance. In addition, the bycatch of species that are protected, threatened, or endangered is also generally condemned by society, even when the bycatch is unintentional. From an ecological perspective, bycatch can lead to overfishing because it increases the uncertainty around estimates of total fishing mortality, making it difficult for fisheries managers to assess sustainable fishing levels (NMFS, 1998). Finally, the biological and ecological impacts of bycatch are poorly understood in terms of bycatch effects on non-target marine populations, on marine communities through changes in food web and competitive interactions among species, and on ecosystems due to changes in energy transfer. Bycatch can be defined as ‘‘the portion of the catch that is discarded at sea dead or injured to an extent that death is the result’’ (Hall et al., 2000). Bycatch includes individuals of species that are targeted in other fisheries, juveniles of species that would be valuable if caught as adults, and species that have no economic value, but that may be important to marine ecosystems. Additional categories of bycatch are protected species such as marine mammals, sea birds, and sea turtles, which are species that fall under special conservation laws (Hall et al., 2000), prohibited species, or species that are reserved for other commercial or recreational fisheries, and regulatory discards, or individuals that must be discarded because of regulatory measures such as size limits, bag limits, or closed seasons (NMFS, 1998). High grading is
the discarding of small individuals of the target species because larger individuals have higher value, or discarding of species with a lower value to capture individuals of higher value (Hall et al., 2000). Hall (1996) also listed eight classification criteria for bycatch, including (1) the level of spatial stratification, (2) the level of temporal stratification, (3) the level of control fishers have over the bycatch, (4) the frequency of occurrence, (5) the predictability of occurrence, (6) the ecological origins of bycatch, (7) the level and type of impact, and (8) legal or economic considerations. Some bycatch species are restricted in time and space due to limited ranges, patchy distributions, or seasonal movements. Stratification in time and space indicates the degree of separation between bycatch species and fisheries, and indicates situations in which bycatch can be reduced by time and area closures, by fishermen moving to a different location, or by fishing at a different time of day or year. Level of control indicates the differences between fisheries like the tuna purse-seine fishery in the eastern tropical Pacific, where fishermen deliberately net schools of dolphins to catch the tuna that are swimming beneath them, and fisheries where fishermen are unaware of bycatch until the net is retrieved. However, even with passive gear, fishermen can exert some control over their bycatch by the configuration of their net, the length of the tow, or other measures. The frequency of occurrence ranges from rare to common; rare bycatch species are either low in abundance or invulnerable to fishing gear. Ecological origins of bycatch refer to ecological, life history, or physiological characteristics that affect why and how bycatch species are captured. Expanding on Hall’s definitions, most of these factors are combined in the category concerning predictability. A predictable bycatch means that there is a high probability that a given piece of fishing gear will catch a particular bycatch species, for example, a predictable bycatch occurs in a nonrandom place or time, when fishermen have a high level of control over catching a bycatch species, when bycatch is caught frequently, or when a bycatch species exhibits characteristics or behaviors that increase the probability of being caught. The category concerning level of impact indicates how much effort will probably be spent on reducing bycatch in a particular fishery. The more that is
209 known about where, when, how, and why species are caught as bycatch, the more options there are for reducing the bycatch. Most fisheries have some degree of bycatch. Bycatch occurs because different species overlap at least temporarily in time and space and because fishing gear is not very selective in terms of species. Fisheries are called ‘‘multi-species’’ fisheries when the overlapping species have economic value and can be landed, but are considered ‘‘high bycatch’’ fisheries when overlapping species are discarded. Trawl fisheries are particularly prone to bycatch, because, in a single tow, they capture species that are distributed in small patches over a large area (Murawski and Finn, 1988). Thus, many trawl fisheries are multi-species fisheries and trawl fisheries also have higher bycatch rates than most other fisheries (Alverson et al., 1994).
History of US bycatch programs Although recognition of bycatch problems and techniques to reduce bycatch have probably been around as long as there have been fisheries (Hall et al., 2000), the magnitude of worldwide bycatch was highlighted by a United Nations report in 1994 that estimated fish discards at 27 million mt, about 25% of the worldwide catch (Alverson et al., 1994). In the US, efforts to quantify and reduce bycatch have been ongoing for decades (Higgins and Pearson 1927, Roelofs 1950, a, b). One of the earliest and most publicly visible bycatch issues in the US was the capture of dolphins in tuna purse seines in the eastern tropical Pacific (Hall et al., 2000). Due to extensive observer programs, changes in gear and procedures, training of fishermen, and management actions taken during the 1970s and 1980s, dolphin mortality was reduced from an estimated 133,000 in 1986 to 1877 in 1998 (Hall et al., 2000). Many other bycatch issues emerged in the 1980s, particularly bycatch of protected species, such as marine mammal bycatch in gill net fisheries in the North Pacific, California, and New England (Jones, 1981, Gilbert and Wynne, 1984; Diamond and Hanan, 1986; Wendell et al., 1986), seabird bycatch in North Pacific gill net fisheries (Ainley et al., 1981), and turtle bycatch in Gulf of Mexico (GOM) and South Atlantic shrimp trawl fisheries (Crouse et al., 1987; Holland 1989; Pearce et al., 1989). During the
1990s, the focus of bycatch programs widened to include the bycatch of fishes and invertebrates, and several legislative actions to reduce bycatch were initiated, such as the requirement for bycatch reduction devices (BRDs) in shrimp trawls in the South Atlantic and the GOM (Murray et al., 1992; Federal Register, 1998), and the requirement for New England shrimp trawlers to use Nordmore grates (Ross and Hokenson, 1997). In 1996, the Magnuson–Stevens Act was amended to include a requirement to ‘‘reduce bycatch to the extent practicable’’ in the nation’s fisheries. Despite these efforts, in 2002, an environmental group called Oceana petitioned the Secretary of Commerce to ‘‘initiate rulemaking to establish a program to count, cap, and control bycatch in the nation’s fisheries’’ (Oceana, 2002). One of the specific requests detailed in this letter was to set bycatch caps or quotas, and to close fisheries when either the target species total allowable catch (TAC) or the bycatch quota is reached. In March 2003, the US government declined to initiate rulemaking, stating that solutions were better found for individual fisheries at the regional level (Federal Register, 2003b). In response to comments on bycatch quotas, the National Marine Fisheries Service (NMFS) responded that bycatch limits as well as other approaches to bycatch reduction, including area closures and gear restrictions, should be considered (Federal Register, 2003b). The use of caps or quotas to reduce bycatch can be classified under the management strategy called incentive/disincentive programs (Alverson et al., 1994). This strategy involves using incentives, which are related to the ability to continue fishing, and disincentives, which can include closure of the fishery, temporary loss of the right to fish, fines, expulsion from the fishery, or reduction of future quotas, to induce fishermen to make fishing choices that reduce bycatch. Programs such as these can be successful when the incentives and disincentives are clear, when the disincentives are rigidly enforced, when comprehensive data collection systems can be put into place, and when the political climate allows a fair and equitable system to be implemented initially (Alverson et al., 1994). Individual transferable bycatch quotas, where fishermen are given ownership rights to the resource, are often recommended as a combination of effort reduction and
210 which use fleet quotas under a ‘‘vessel incentive program’’ for prohibited species, (3) the groundfish trawl fishery of British Columbia, which uses individual vessel bycatch quotas for prohibited species, and 4) the multi-species trawl fisheries of New Zealand, which use catch balancing, or individual transferable quotas, for most commercially landed species. Finally, I investigate the similarities and differences between these fisheries and the GOM shrimp trawl fishery and make recommendations and suggestions on using bycatch quotas and other options to manage finfish bycatch in the Gulf of Mexico shrimp trawl fishery.
GOM shrimp trawl fishery The Gulf of Mexico shrimp trawl fishery is one of the most valuable fisheries in the United States, generating landings worth about $500 million annually (NMFS, 2003a). The fishery started in 1917 off Louisiana (Condrey and Fuller, 1992), and shrimp harvest grew from 15,000 mt in 1918 to a peak of 130,200 mt in 1986 (Fisheries Statistics of the United States 1942–1977, NMFS, 2003a). Recent annual landings, which are primarily from Louisiana and Texas, have varied between 85,000 and 110,000 mt since the mid-1980s (Figure 1). The fishery targets three species of Penaeid shrimp: brown
350
140
300
120
250
100
200
80
150
60
100 50 0 1960
40
Shrimp effort Shrimp catch
20
Shrimp Catch (1000s of mt)
Shrimp Effort (1000s of days)
incentive/disincentive programs. Individual quotas are thought to move the impetus for bycatch reduction to the individual fishermen and to change the thinking of fishermen from short-term profits to long-term resource management (Alverson et al., 1994). However, there are some problems with individual quota programs in that management and regulatory costs for these programs can be prohibitive, opportunities for young fishers to enter the fishery may be limited, and high grading can be significant. The use of any incentive/disincentive program and how it might be used to reduce bycatch must be evaluated individually for each fishery (Alverson et al., 1994), and any program must be tailored to accommodate the needs of participants, the logistics of the fishery, and the goals of the fishery managers. The purpose of this paper is to explore the potential use of quotas to reduce bycatch in the GOM shrimp trawl fishery. First I briefly detail the characteristics of the GOM shrimp trawl fishery that are relevant to bycatch reduction, and the history of bycatch reduction measures in this fishery. Next, I explore case histories of fisheries where four types of incentive/disincentive programs are used to manage bycatch. These fisheries are the (1) a squid trawl fishery of New Zealand, which uses fleet bycatch quotas for sea lion bycatch, (2) the Alaskan groundfish trawl fisheries,
0 1970
1980
1990
2000
Year Figure 1. Shrimp effort and catch in the Gulf of Mexico shrimp trawl fishery. Shrimp trawl effort (grey line) is measured in thousands of standardized days and is based on information from the National Marine Fisheries Service (J. Nance, NMFS – Galveston Laboratory, unpubl. data). Shrimp catch (black line) includes the catch of brown, white, and pink shrimp by otter trawls and unspecified trawls, and is measured in thousands of mt (NMFS, 2003a).
211 shrimp (Farfantepenaeus aztecus), which is the primary species, white shrimp (Litopenaeus setiferus), which is the secondary species, and pink shrimp (Farfantepenaeus duorarum), using mainly otter trawls. Because these species live only one year, annual landings vary mostly in response to environmental conditions (Nance, 1993a,b), and no TAC is set for these species. None of these species have ever been considered recruitment overfished, or fished down to such a low level that the stock’s ability to replace itself is impaired (Nance, 1993a,b), although there are regulations, such as the Texas Closure for brown shrimp (Nance et al., 1989), designed to prevent the harvesting of individuals at too small a size, called growth overfishing. The shrimp trawl fishery is an open access fishery, with an estimated 20,000 vessels participating in state and federal waters (NMFS, 1998). Over 16,000 vessels, ranging from about 8 to 28 m in length, had state shrimp licenses in 1998 (Table 1, Woodward et al., 2002). Vessels have only been required to apply for a federal shrimp permit since December 2002 (Federal Register, 2002). As of July 2003, about 2800 vessels had applied for a permit (NMFS-SEFC Permit Office, unpubl. data), although the actual number of
working vessels in the fleet is unknown. Total effort for all three species has been estimated at about 250,000 standardized fishing days per year during the 1990s, down from the peak of almost 350,000 effort days in 1987 (Figure 1, Nance et al., 1998). Current economic conditions in the shrimp fishery are depressed. Imports of farm-raised shrimp from Southeast Asia and South America have heavily impacted shrimp markets, and wild shrimp from the GOM now make up only 14% of the domestic shrimp market (Haby et al., 2003). In 2002, the European Union raised its tariffs on imported shrimp from Thailand, leading to dumping of foreign shrimp on US markets and a drastic reduction in price (Haby et al., 2003). The situation was so bad that in 2003, the US government provided emergency disaster relief of $17.5 million to GOM shrimpers (Federal Register, 2003c).
Bycatch in the GOM shrimp trawl fishery Since the 1980s, bycatch in the Gulf of Mexico shrimp trawl fishery, first of sea turtles and more recently of finfish, has been one of the most
Table 1. Number of state shrimp licenses for shrimping in state waters by state and vessel length (m) in 1998 Length (m)
Florida
Alabama
Mississippi
Louisiana
Texas
>6.2 6.2–7.7 7.7–9.2 9.2–10.8 10.8–12.3 12.3–13.8 13.8–15.4 15.4–16.9 16.9–18.5 18.5–20.0 20.0–21.5 21.5–23.1 23.1–24.6 24.6–26.2 >26.2 Total
27 43 73 162 189 149 123 57 47 49 181 47 19 6 7 1179
263 260 181 42 65 74 51 38 32 24 21 19 23 15 3 1111
119 118 82 77 120 137 137 101 87 65 55 51 62 41 9 1261
4531 1788 1124 713 487 252 273 152 151 80 44 68 44 34 37 9778
83 133 156 297 436 283 223 93 60 172 399 203 226 155 69 2988
The table is taken from Woodward et al., (2003). Data for Florida, Mississippi, and Texas are from NMFS, Southeast Regional Office. Alabama data are from the Alabama Department of Conservation and Natural Resources. Data for Louisiana are from the Louisiana Department of Wildlife and Fisheries. All information is for 1998 except for Mississippi, which uses data from 2000.
212 controversial and intractable fishery management problems in the region. All species of sea turtles that occur in US waters are listed as either threatened or endangered, and trawling has been implicated as a major source of mortality (Crouse et al., 1987; NRC, 1990). Regulations that GOM shrimp trawls carry turtle excluder devices (TEDs), which are hard grates or soft liners that allow turtles to escape the nets, went into effect in federal waters in Spring 1990 (Federal Register, 1987), despite fierce protests from the shrimp industry. Populations of Kemp’s ridley turtles have increased dramatically since that time, from fewer than 800 nests at the primary nesting beaches in Mexico in the mid-1980s (Marquez Millan et al., 1989) to over 8000 nests in 2003 (Burchfield and Pena, 2003). This increase is due at least partly to TED regulations. TEDs are still being refined to further reduce the catch of larger turtles such as leatherbacks (Federal Register, 2003a). Fishery managers first noticed finfish bycatch in the GOM shrimp trawl fishery in the 1930s (Gunter, 1936; Lindner, 1936), but until the 1980s, most researchers concluded that bycatch had little effect on non-target fish populations. This lack of effect was thought to be because (1) bycatch fish are mostly juveniles and natural mortality is so high in the juvenile stage that most bycatch fish would not have survived to adulthood anyway (Lunz et al., 1951), (2) bycatch had been occurring for decades without major changes in species composition or numbers taken (Keiser, 1976; Bryan et al., 1982), and (3) environmental factors were thought to have a stronger influence on populations than bycatch (Gunter, 1956). Some authors believed that bycatch could be beneficial to fish stocks by reducing competition for food, thus increasing the sizes of fish that were left through density dependent compensation (Lunz et al., 1951; Gunter 1956; Bryan et al., 1982). In the 1950s, the pet food industry began to utilize bycatch, and by 1952, there was a directed fleet of trawlers targeting the juvenile groundfish that had previously been discarded in the shrimp trawl fishery. This fishery averaged over 40,000 mt landed annually between 1957 and 1977 (Roithmayr, 1965; Fisheries Statistics of the United States, 1977) and then dropped to less than 100 mt landed in 1978. The sudden drop in
Table 2. A summary of the literature on bycatch characterization and the population effects of bycatch in the Gulf of Mexico and the South Atlantic shrimp trawl fisheries Author
Year
Species
Gulf of Mexico and South Atlantic NMFS
1992a 1995 1998 1999 2000 2004
Protocol for bycatch characterization All All Atlantic croaker Atlantic croaker All
1956 1969 1976
All Small brown shrimp All
1980 1982 1982
Groundfish All LA vs TX catch rates Snappers and groupers Offshore species Selected species Red snapper Red snapper Red snapper Offshore species Red snapper All
NMFS Nance et al. Diamond et al. Diamond et al. Scott-Denton Gulf of Mexico Gunter Berry and Benton Chittenden and McEachran GMFMC Pellegrin Watts and Pellegrin Gutherz and Pellegrin
1986
Nichols et al. Powers et al. Gutherz and Pellegrin Goodyear and Phares Nichols Nichols et al. Goodyear Pellegrin et al.
1987 1987 1988 1990 1990a 1990 1991 Undated 1992 1992 1994 1994
Goodyear Nichols and Pellegrin Goodyear Nichols Wallace and Robinson Cortes Goodyear Nichols Nichols Schirripa and Legault Workman Gulf of Mexico – Florida Siebenaler Burgess and Snyder Meyer et al.
Red snapper Offshore species Red snapper King and Spanish mackerel 1994 Recreational shrimp bycatch 1995 Atlantic sharpnose shark 1995 Red snapper 1996a Red snapper 1996b Mackerels and cobia 1999 Red snapper 1999 Red snapper
1952 1993 1999
All All, inshore Seagrass beds, fishes
213 Table 2. (Continued) Author
Table 2. (Continued) Year
Species
Baum et al.
2003
Seahorses
Gulf of Mexico – Mississippi Warren
1981
All
Gulf of Mexico – Louisiana Gunter 1936 Lindner 1936 Adkins 1993 Baltz 1993
All All All All, inshore
Gulf of Mexico – Texas Bryan et al. Fuls Carter and Colura Colura and Bumguardner
1982 1995 1996 2001
All All, coastal bays Bycatch survival Bycatch survival of selected species
Gulf of Mexico – Mexico Castro-Gonzales et al.
1998 2000
Chemical composition of bycatch Small brown shrimp
South Atlantic Anderson Keiser Vaughan et al. Peuser Vaughan and Nance
1968 1977 1991 1996 1998
All All Weakfish Selected species Mackerels and cobia
South Atlantic – Florida Anderson and Gehringer
1965
All
South Atlantic – Georgia Knowlton Hoese
1972 1973
All, nearshore All, nearshore
South Atlantic – South Carolina Keiser Bearden et al. Harris and Dean
1976 1985 1998
All All, sounds and bays King and Spanish mackerel
South Atlantic – North Carolina Roelofs Latham Lunz et al. Fahy Fahy Fahy Brown and McCoy
1950b 1951 1951 1965a 1965b 1966 1969
All All, Pamlico Sound All, Pamlico Sound All All All Selected species
Arreguin-Sanchez and Castro-Melendez
Author
Year
Species
Wolff Purvis and McCoy
1972 1974
Diamond
1999
All All, Core and Pamlico Sounds All, estuarine and nearshore
‘‘All’’ as a species indicates that the study was a general characterization of bycatch in a particular area. Studies from the South Atlantic shrimp trawl fishery are included because the fisheries are so similar.
landings was primarily due to rising fuel costs, declining catch per unit effort for groundfish, and higher shrimp prices, which caused most of the trawlers to return to shrimping (GMFMC, 1980). During turtle bycatch research on shrimp vessels in the 1980s, finfish bycatch was again observed to be a significant component of the catch. ‘‘Finfish’’ bycatch, which consists mainly of juvenile fishes, adults of small fish species, and many species of invertebrates, totals an estimated 100,000 to 400,000 mt annually (Nichols et al., 1987, Nichols et al., 1990). Red snapper (Lutjanus campechanus), a species with large directed commercial and recreational fisheries is the most controversial fish species caught as bycatch in the GOM. On average, an estimated 25–30 million juvenile red snapper are caught annually in shrimp trawls (Ortiz et al., 2000). Red snapper bycatch is an especially contentious issue because strict regulations on directed red snapper fisheries (commercial and recreational) have been in place since 1990 (Goodyear, 1995), when a stock assessment for red snapper showed that 90% of the mortality on age 0 and 1 fish was caused by bycatch (Goodyear and Phares, 1990). The problem of shrimp trawl bycatch in the GOM and the South Atlantic was considered to be of such magnitude that the Magnuson Fishery Conservation and Management Act was amended in 1990 to include bycatch research. This amendment mandated the creation of a program to assess the impact of incidental harvest by the shrimp trawl fisheries, including the nature and extent of bycatch, its effects on fish stocks, and ways to reduce the bycatch (Hoar et al., 1992). Starting in 1992, observers sponsored jointly by the shrimp industry (through the Gulf and South Atlantic
214 Fisheries Development Foundation, or GASFDF) and NMFS rode aboard paid volunteer shrimp boats to characterize the bycatch and to test BRDs (see Scott-Denton, 2004 for details), using sampling protocols developed by NMFS (NMFS, 1992a, b). Between 1992 and 1997, before BRDs were required in federal waters, bycatch in the GOM made up an average of 84% of the catch by weight and 71% by number. Several hundred species were documented in the catch, with longspine porgy (15%, Stenotomus caprinus), brown shrimp (9%), and Atlantic croaker (9%, Micropogonias undulatus), making up the largest components of the overall catch by weight, although catches varied by season and location (Nance et al., 1997). In all, an average of 28 kg per hour, or 1350 organisms per hour were captured during trawling in the GOM (Nance et al., 1998). In addition to the NMFS/GASFDF observer study, other bycatch characterization studies were conducted during the 1990s, with researchers riding aboard commercial boats or trawling with commercial gear from research boats to characterize the bycatch in local areas. Other studies focused on estimating the magnitude of the bycatch and on assessing the population-level effects of bycatch for certain species (see the literature summary in Table 2). Bycatch reduction using gear modifications was also a major focus of bycatch research during the 1990s. BRD designs were evaluated by NMFS, state fishery agencies, Sea Grant agents, and university biologists using controlled comparison studies (modified nets versus unmodified nets) aboard research and commercial vessels (see the literature summary in Table 3). These controlled studies showed that although BRDs were effective at reducing the bycatch of species such as Atlantic croaker, fish like red snapper that orient to structure are very difficult to passively remove from nets using BRDs. These fish are attracted to the net, which they apparently consider to be structure (NMFS, 1998). In addition, most studies found that bycatch reduction using BRDs was extremely variable and depended not only on BRD design, but also on the placement of BRDs in the net, individual fishing practices, and fishing conditions. More recent advances in bycatch research in the Southeastern US include improvements in the statistical methods used to estimate the magnitude
Table 3. A summary of the literature on bycatch reduction in the GOM and South Atlantic shrimp trawl fisheries including gear modifications, gear selectivity studies, management alternatives, and studies of fish behavior in trawls Author
Year
Subject
Gulf of Mexico and South Atlantic Watson et al. 1986 Watson 1989 Renaud et al. Watson and Taylor Renaud et al. Workman et al. NMFS Watson Watson et al. Workman et al. GSAFDF NMFS Watson Watson Branstetter Watson and Shah Nance et al. Watson et al. Gulf of Mexico Berry and Harvey Nichols NMFS Perret and Bowman Workman and Watson Ehrhardt Watson et al. Engaas et al. Nichols Watson et al. Foster and Scott-Denton Parsons
Gulf of Mexico – Florida Coleman et al. Coleman et al. Steele et al.
Gear selectivity Fish behavior and trawl design 1990 Bycatch reduction of TEDs 1990 Gear selectivity 1991 Bycatch reduction of TEDs 1992 BRDs 1992b Protocol for BRD testing 1993 BRDs 1993 BRD design 1994 BRDs 1995 BRDs 1995 BRDs 1995 BRDs 1996 BRDs 1997 BRDs 1997 BRDs 1998 BRDs 1999a BRDs
1964 Mesh selectivity 1990b Bycatch reduction alternatives 1993 BRDs 1993 Butterfly and skimmer nets 1995 BRD certification 1996 TEDs/BRDs 1997 BRDs 1999 BRDs 1999 BRDs 1999b BRDs 2004 BRDs 2004 Red snapper behavior /BRDs
1991 1992 2002
Gulf of Mexico – Louisiana Rogers et al. 1994 Rogers et al. 1997a
BRDs BRDs BRDs
BRDs BRDs
215 Table 3. (Continued) Author Rogers et al. Rogers et al.
Year
Subject
1997b BRDs 1998 BRDs
Gulf of Mexico – Texas Fuls
2001
BRDs
South Atlantic Christian and Harrington Rulifson et al. Christian et al. Harrington SAFMC
1987 1992 1993 1996 1996
TEDs/BRDs BRDs BRDs BRDs BRD testing protocol manual BRD technology transfer
Vendetti et al. South Atlantic – South Carolina Wenner Whitaker et al. Stender and Barans South Atlantic – North Carolina Holland Pearce et al. McKenna and Monoghan Coale Murray et al. Bahen et al.
1996
1987 1989 1994
TEDs Closures Tongue vs. 2-seam trawls
1989 1989 1991
Bycatch reduction Bycatch reduction BRDs
1992 1992 1993
Skimmer trawls Management TED/BRD combinations BRDs
McKenna and Monaghan Coale et al. Murray et al. Murray et al. Gearhart McKenna McKenna et al. Lupton Hines et al.
1993 1994 1994 1995 1996 1996 1996 1998 1999
Morris
1999
Skimmer trawls BRDs Large mesh webbing Large mesh webbing BRDs BRDs BRDs Low profile skimmer trawls BRDs
‘BRDs’ as a subject indicates that one or more specific BRD designs were tested, usually against a control or unmodified net. Studies from the South Atlantic shrimp trawl fishery were included because the fisheries are so similar.
of bycatch and new techniques for estimating effort in the shrimp fleet (see the literature summary in Table 4). Statistical methods include simulations to uncover biases in different estimation methods, the use of lognormal distributions and Bayesian analyses to estimate bycatch, and an exploration of using spatial analyses to fill in estimates for strata without sufficient data. Recent research in estimating shrimp fleet effort includes the use of electronic logbooks, improvements in data collection, and improvements in the statistical estimation of effort. Although the ecosystem effects of shrimp trawling have recently become high priority topics for investigation in other areas of the world, there are relatively few ecosystem studies targeting GOM shrimp trawl bycatch (see literature summary in Table 5). Ecosystem effects include indirect bycatch effects on non-bycatch species and communities and the effects of trawling on bottom habitats. Certification procedures for BRDs were created by NMFS during the early 1990s to ensure that the BRDs used by fishermen met specific criteria for bycatch reduction, particularly for species of management concern. Originally, certification for BRD designs in the GOM was based on reductions of age-0 and age-1 red snapper bycatch mortality of 44% as compared to fishing mortality from 1984 to 1989 (Federal Register, 1998). Currently, only Florida and Texas require BRDs in state waters of the Gulf of Mexico. In federal waters, BRDs were required in the GOM in 1998. Two BRDs, the Jones-Davis BRD and the Gulf Fisheye, have been certified for use in the GOM since 1998 (Foster and Scott-Denton, 2004), but the specific position of the BRD in the net has not been regulated in federal waters of the GOM. Unfortunately, bycatch reduction using BRDs during actual commercial fishing operations has not lived up to expectations. Based on the 1998 NMFS/GASFDF observer program aboard commercial vessels, it was estimated that about 23% of juvenile red snapper escaped from nets with certified BRDs compared to control nets (Nichols, 1999). That estimate included a particular placement of the Fisheye BRD that has since been disallowed, and the reduction in red snapper bycatch improved to 41% reduction when those data were removed from the analysis. It was hoped that further reductions would occur as fishermen be-
216 Table 4. A summary of the literature on statistical techniques for estimating total bycatch from samples, estimating effort in the shrimp trawl fisheries and estimating bycatch reduction using BRDs Author
Year
Gulf of Mexico and South Atlantic Shah 1999 Diamond Nichols Nichols Gulf of Mexico Nance Nance Griffin and Shah Nichols et al. Ortiz et al. Gallaway et al. Gallaway et al. Griffin Jones Jones Nance
Subject
Estimating reduction 2003 Estimating 2004a Estimating 2004b Estimating
BRD bycatch bycatch bycatch
1992
Estimating shrimp trawl effort 1993b Estimating shrimp trawl effort 1995 Estimating shrimp trawl effort 1995 Estimating bycatch reduction 2000 Estimating bycatch 2003a Electronic logbooks 2003b Electronic logbooks 2004 Estimating shrimp trawl effort 2004a Estimating bycatch 2004b Estimating bycatch 2004 Estimating shrimp trawl effort
Eastern Tropical Pacific Perkins and Edwards
1996
Estimating bycatch
Middle East Ye
2002
Estimating bycatch
Australia Wassenberg et al.
1998
Burridge and Robbins Heales et al. Heales et al. Heales et al.
Research vs. commercial tows 2000 Statistics of BRD tests 2000 Subsampling bias 2003a Subsampling bias 2003b Subsampling bias
Studies from locations other than the Gulf of Mexico are shown because the topics are relevant to estimating bycatch regardless of location.
came more familiar with using BRDs, so a projected 50% overall reduction of red snapper bycatch was used in 1999 to set the TAC of red
Table 5. A summary of the literature on the ecosystem effects of shrimp trawl bycatch in the Gulf of Mexico Author
Year
Subject
Gulf of Mexico Cushing
1984
Discards and shrimp production Shrimp and fish interactions Ecosystem models Ecosystem models Ecosystem models Ecosystem models Ecosystem effects Ecosystem models
Sheridan et al. Browder Brown et al. Browder Browder Martinez et al. Martinez et al. Gulf of Mexico – Florida Hensley and Hensley
1984 1983 1991 1992 1993 1993 1996 1995
Effects on sooty terns and brown noddies
Gulf of Mexico – Texas Fertl
1994
Effects on bottlenose dolphins
Gulf of Mexico – Mexico Arreguin-Sanchez et al.
2004
Harvesting strategy effects on ecosystems
snapper in the directed fisheries at 9.12 million pounds annually between 2000 and 2005 (RFSAP, 1999). In addition, a red snapper rebuilding plan was drafted calling for red snapper bycatch reductions of up to 80% to be phased in over time (GMFMC 2002). Contrary to these optimistic projections, observations from the 2001–2003 observer program showed that bycatch reduction has declined over time, and now averages only 11.7% for red snapper and 16.5% for all species (Foster and Scott-Denton, 2004). The reason for the observed decrease in bycatch reduction is that fishermen modify their nets or change their practices to reduce the loss of shrimp, which also reduces the efficiency of BRDs. Recent advances in technology such as the use of infrared lights and low-light video cameras during BRD testing (Foster and Scott-Denton, 2004) and stricter regulations and enforcement on BRD placement should help to improve BRD performance in future, but it is unlikely that gear modifications alone will make trawl nets completely speciesselective, or even meet the level of bycatch reduction required by the red snapper rebuilding plan.
217 Case study: 1. The New Zealand squid fishery and Hooker’s sea lions The trawl fishery for arrow squid (Nototodaurs sloanii) in the Auckland Islands off New Zealand is managed by a fleet bycatch quota. The squid fishery began in 1979 and has been managed by New Zealand’s Quota Management System (QMS), which is an individual transferable quota, or ITQ system, since 1986. Hooker’s sea lions (Phocarctos hookeri), a threatened pinniped species, are incidentally killed in squid trawls near their rookeries (Maunder et al., 2000). The Hooker’s sea lion population is currently estimated at about 13,000 animals (Manley et al., 2002). Because Hooker’s sea lions are protected, a kill limit for them has been set each year starting in 1992 by the Ministers of Fisheries and Conservation based on population models of sustainable mortality levels (Table 6, Maunder et al., 2000). The limit, initially called the MALFIRM, or maximum allowable fishing-related mortality, and now called the FRML, or fishing-related mortality limit, is the estimated level of mortalities that a marine mammal population can sustain while still reaching management objectives such as population growth (Thomas, 2002). Based on the provisions of the 1996 Fisheries Act, the Minister of Fisheries is legally obligated to insure that the limit is not exceeded (Royal Forest and Bird Protection Society of New Zealand, 2003a). Department of Fisheries observers are supposed to monitor at least 20% of the effort per year (Maunder et al., 2000), and the number of sea lion kills is estimated by extrapolation of the data they collect (see Manley et al., 2002). Although the MALFIRM or FRML was never above 80 animals until the 2003/2004 season, annual estimated sea lion deaths ranged from 14 in 1998/99 to 123 in 1996/97 (Table 6). During the 1997/98 season, the bycatch quota was reduced 20% from 79 to 63 animals because of a mysterious illness that killed over 53% of the pups born that year and an unknown number of adults, perhaps as many as 20% of the adult population. Similarly, about 25% of the pups born in both 2002 and 2003 also died of disease (Royal Forest and Bird Protection Society of New Zealand, 2003b). Squid landings in the Auckland Islands trawl fishery have always been variable, ranging from
950 tons to over 34,000 tons since 1986, although the Auckland Islands quota has never been below 30,000 tons. The catch has ranged from 3% to 114% of the total allowable commercial catch, or TACC (Royal Forest and Bird Protection Society of New Zealand 2003b, New Zealand Ministry of Fisheries, 2004a). Much of the variability in landings is due to environmental conditions, because arrow squid are an annual species similar to Penaeid shrimp in the GOM. According to one environmental group, research into squid ended in 1993 (Royal Forest and Bird Protection Society of New Zealand, 2003b), so the squid quota is now set arbitrarily, although apparently the quota was originally set on the basis of average catches levels (McKoy, 1988 cited in Boyd and Dewees, 1992). In 2001, there were 25 boats in the New Zealand squid fleet (Thomas, 2002), mostly foreign vessels fishing for New Zealand companies (Royal Forest and Bird Protection Society of New Zealand, 2003b), although not all of them fished at the Auckland Islands. Effort in the Auckland Islands fishery between 1987 and 1995 ranged from a low of 666 tows in 1992 to a high of 5218 tows in 1989, with observer coverage ranging from 7% to 24% (Manley et al., 2002). The fishery usually runs from about February to May, although excessive kills of Hooker’s sea lions caused the season to close early in five of the nine fishing years since 1995 (Table 6). The 2002/03 season was initially closed on March 29, 2003 with an estimated 79 sea lions killed, exceeding the quota of 70. This estimate was based on a default ‘‘strike rate’’ of 9.4%, or 9.4 sea lions killed per 100 tows (Logan, 2003) that was applied when the squid fleet failed to maintain the minimum level of 20% observer coverage. The squid industry challenged the closure in court on the basis of gear modifications (sea lion exclusion devices, or SLEDs) that reduced the bycatch rate of sea lions (80–90% escapement with 20–40% survival), an observed strike rate in the early season of 1.3%, and disagreement about whether sea lions killed while testing the SLEDs should be counted against the industry (Logan, 2003). The court estimated that only 30 sea lions had been killed, and reopened the fishery. The agreement between the industry and the New Zealand government for reopening the season was that the fleet would maintain a minimum of 20% observer coverage, or the season would be closed again (New Zealand Ministry of
218 Table 6. The Auckland Islands arrow squid fishery of New Zealand and the bycatch of Hooker’s sea lions Year
TACC
Squid Catch
1986/87 1987/88 1988/89 1989/90 1990/91 1991/92 1992/93 1993/94 1994/95 1995/96 1996/97 1997/98 1998/99 1999/2000 2000/01 2001/02 2002/03 2003/04
32,333 32,333 35,933 42,118 30,190 30,190 30,369 30,369 30,369 30,369 30,369 30,369 30,369 32,369 32,369 32,369 32,369 32,369
16,025 7021 33,462 19,859 10,658 10,861 1551 34,534 30,683 14,041 19,843 7344 950 6241 3254 11,502 6887 34,634
MALFIRM or FRML
Sea Lion Kills
Closure
32 63 63 69 73 79 79/63a 64 65 75 79 70 62+27 from SLED testing/124
33 141 117 21 82 17 32 109 101 123 62 14 71 67 84 79/39 118
4-May-96 28-Mar-97 27-Mar-98 None 8-Mar-00 None 13-Apr-02 Noneb Nonec
The fishing season runs from about February to May, so landings for 1986/87, for example, took place in 1987. Data were obtained from the New Zealand Ministry of Fisheries (2004b). After 1996, closures were enacted when the maximum allowable fishing-related mortality (MALFIRM), now called the fishing-related mortality limit (FRML), was reached. The arrow squid catch is variable because it is an annual species, and therefore highly affected by environmental conditions. a The 1997/98 MALFIRM was adjusted by 20% downward when a mysterious disease killed many of the sea lion pups and adults. b The 2002/03 fishery was initially closed on 29 March 2003 when an estimated 79 sea lions were killed, but the closure was stopped by a court injunction obtained by the fishing industry, and an alternate procedure for estimating mortalities resulted in an estimated mortality of 39 sea lions. The fishery voluntarily closed at the end of June. c The initial 2003/04 closure date of 22 March 2004 was set aside by a court order, which allowed for 124 sea lion mortalities instead of the 62 sea lions allowed to be caught as bycatch in the Operational Plan, plus 27 sea lions that were estimated would be killed while testing the sea lion excluder devices, or SLEDS.
Fisheries, 2003a,b). For the 2003/04 season, the Ministry of Fisheries set a kill limit of 62 sea lions, excluding the estimated 27 sea lions that potentially could be killed during SLED testing. This limit was also challenged in court, and the court allowed for continued fishing providing incidental sea lion captures did not exceed 124 (New Zealand Ministry of Fisheries, 2004b). The 2004/05 Draft Operational Plan explains the options on setting the FRMT in future years (New Zealand Ministry of Fisheries, 2004b). The arrow squid fishery is worth $50 million or more annually, depending on landings, so early closures can result in the loss of millions of dollars. It has been estimated that early closures cost up to $20 million (NZD) per year, but since landings in the squid fishery are so variable (Thomas, 2002), financial losses in any given year
due to closures are hard to estimate. An analysis of losses in the squid fishery due to sea lion quotas estimated that the squid fishery is much more sensitive to closures than the sea lions, i.e. the fishery shows much greater losses than the sea lion population shows gains under the closures (Maunder et al., 2000). Even with the sea lions killed in the squid fishery, the sea lion population is not in danger of extinction, and may actually be at carrying capacity (Breen et al., 2003). The squid fishery also has other controls to manage the take of bycatch species. A 12 nautical mile closure around the sea lion breeding grounds was instituted in 1982 (Maunder et al., 2000), and this area was inducted into the Marine Reserve Program in January 2003 (New Zealand Ministry of Fisheries, 2003c). An additional management measure that operates in the squid fishery and
219 other fisheries is the vessel monitoring system (VMS) that was introduced in 1994 (Meister, 1999). All foreign vessels inside the 200-mile exclusive economic zone (EEZ), all New Zealand vessels larger than 28 m and all vessels targeting orange roughy, scampi, squid, and tuna carry automatic transponders whose signals are picked up by satellite, so that the vessels locations are constantly monitored. The VMS system is useful for enforcement of prohibited areas, and for matching catches to areas fished. The New Zealand Air Force also contributes to surveillance, and planes can detect dumping at sea and other infractions (Meister, 1999).
Case study: 2. Pacific halibut in the Alaska groundfish trawl fisheries The groundfish fisheries in the eastern Bering Sea (BSAI) are some of the largest and most valuable fisheries in the US (NMFS, 1998). Flounders such as yellowfin sole (Limanda aspera) and rock sole (Lepidopsetta bilineata), rockfishes (Sebastes spp.), sablefish (Anoplopoma fimbria), pollock (Theregra chalcogramma), and Pacific cod (Gadus macrocephalus) are caught primarily with trawl gear, although other gears are also used for some species. Fishermen can catch several species with the same trawl gear, and the target species is determined by the composition of the retained or landed catch (Renko, 1998). All target species have quotas, and many other species are caught as bycatch, including six prohibited species, which are Pacific halibut (Hippoglossus stenolepis), Pacific herring (Cluepa harengus pallasi), Pacific salmon and steelhead trout (Onchorhynchus spp.), king crabs (Paralithodes and Lithodes spp.), and Tanner crabs (Chionoecetes spp). Fleet bycatch quotas exist for these species, and target fisheries are closed when the bycatch quota for any species is reached. In the past several years, many fisheries have closed early due to fleet bycatch quotas being reached, particularly the quotas for Pacific halibut and Pacific herring (NMFS, 2003b). In addition to fleet bycatch limits, individual vessel bycatch rates are also calculated and can be used to prosecute fishers whose monthly bycatch rates exceed a preset standard rate. In the 1950s through the 1970s, most of the Bering Sea fisheries in US waters were conducted
by foreign nations such as Japan and the USSR. In 1976, the US expanded its fishery management to 200 miles and prohibited foreign fishing except to licensed vessels under specific conditions, which included mandatory observer coverage (Renko, 1998). A preliminary Fishery Management Plan (FMP) for Bering Sea groundfish fisheries was implemented in 1977, in large part to instigate rebuilding of the Pacific halibut stocks, which had been declining since the 1960s (Witherell and Pautzke, 1997). The final FMP took effect in 1982, although the fisheries at that time were still primarily conducted by foreign vessels. The first bycatch cap was written as an amendment to the FMP for Chinook salmon (O. tshawytscha) in foreign trawl fisheries. The limit was 55,250 salmon, allocated among the foreign nations, and any nation that exceeded their allocation was prohibited from fishing for the rest of the season. In 1983, the FMP was amended to reduce the bycatch of Pacific halibut, Pacific salmon, and king and Tanner crabs by specified percentages over a 5-year period. This program was an incentive/disincentive program, with supplemental fishing rights given to nations that reduced bycatch, while nations with high bycatch faced expulsion from the fishery or low quota rights the following year (Alverson et al., 1994). The Japanese fleet, by setting up individual vessel bycatch accounts, was very successful at reducing bycatch. The total bycatch allowance was initially allocated among three vessel associations, and each association then allocated species quotas among member vessels (Alverson et al., 1994). If a vessel exceeded its individual bycatch quota for any species, it either had to purchase unused bycatch shares from another vessel, which were rarely available, or stop fishing. Between 1985 and 1988, the fisheries transitioned from foreign fisheries to domestic fisheries, first using joint venture operations, and then moving to fully domestic operations by 1991. During the transition time, although there were relatively few regulations placed on the domestic fleet to give domestic fishermen a competitive edge (Trumble, 1992), limits for the catch of prohibited species (called PSC limits) in certain areas were specified for king crab, Tanner crab, and Pacific halibut in the flatfish fisheries (Witherell and Pautzke, 1997). When bycatch limits were reached, vessels were prohibited from fishing in that area.
220 Disincentives such as the loss of fishing rights were also used in some joint-venture USSR fishing operations (Fisher, 1992). These disincentives were effective at reducing halibut bycatch rates by over 90% (Renko, 1998). In 1989, the PSC limits were extended to all trawl fisheries, and by 1992 halibut bycatch limits were extended to non-trawl fisheries. The bycatch quotas were changed at that time from total allowable catch to total allowable mortality, acknowledging that not all halibut caught as bycatch are killed (Renko, 1998). PSC limits were also allocated by fishery and season. By 1990, although the groundfish fisheries were still open access fisheries, over 90% of the Alaska groundfish were caught with trawl gear from 226 vessels (Renko, 1998). Bycatch mortality information was gathered by onboard observers, under a mandatory observer program. All domestic groundfish vessels over 125 feet in length were required to carry an observer at all times. Vessels between 60 and 125 feet were required to carry an observer for 30% of the fishing days each fishing quarter (Renko, 1998). Vessels less than 60 ft were not required to carry observers. Bycatch rates were expanded to estimate bycatch totals, and individual fisheries were closed when the halibut bycatch quota was met. The fleet quota was based on a fixed amount, rather than a percentage of the estimated halibut population, which was intended to ratchet down the bycatch amount, similar to the bycatch reduction strategy used in the joint venture fleet (Renko, 1998). Halibut bycatch limits triggered fishery closures in several groundfish fisheries for the first time in 1990, leaving allocated quotas of the target species unharvested, and losing an estimated $15 million in the Gulf of Alaska and $41 million in the BSAI (Renko, 1998). Six closures were implemented in 1994, 12 in 1995, and 14 closures in 1996 due to halibut limits being reached (Witherell and Pautzke, 1997). Closures have continued through the present day (NMFS, 2003b). The North Pacific Fishery Management Council (the North Pacific Council) moved in 1990 to reduce bycatch by introducing vessel incentives and disincentives. Suggested measures included the ‘‘penalty box’’ program, where vessels with high bycatch rates would be temporarily suspended from fishing; the bycatch credit system, where vessels with low bycatch rates would gain additional fishing access after the open access fisheries
were closed; and the reserve system, where vessels with low bycatch rates would gain a reserved portion of the halibut quota (Renko, 1998). After much discussion, the North Pacific Council adopted the penalty box program, with the idea of holding individual operators responsible for excessive bycatch rates. Unfortunately, the penalty box program was disapproved by the Secretary of Commerce based on concerns about due process and the use of preliminary observer data as the basis for sanctions (Witherell and Pautzke, 1997; Renko, 1998). The North Pacific Council then implemented the vessel incentive program, or ‘VIP’, which used monetary penalties rather than lost fishing time for vessels exceeding monthly bycatch rate standards (Witherell and Pautzke, 1997; Renko, 1998). These penalties were designed to be so high that it would be economically advantageous for vessels to comply with the bycatch standard. Although proposed penalties in the VIP program were a maximum of $400,000–$500,000 per month, with the potential for permit restrictions and vessel seizures, the penalties finally established by the NOAA General Counsel were very different, with a penalty of $50,000 per month for first time offenders, and a maximum of $90,000 for repeat offenders. Bycatch rates (ratio of halibut bycatch to groundfish catch by weight) were based on verified observer data and standards were set before the season opening. The VIP program was initially implemented in groundfish fisheries with high historic halibut bycatch rates, fisheries that took a large proportion of the halibut bycatch allowance compared to groundfish, and fisheries that closed early because they reached halibut bycatch limits (Renko, 1998). By 1993, the VIP was expanded to all Alaska trawl fisheries. Unfortunately, due to insufficient staff resources, very few cases have been prosecuted. Between 1991 and 1996, only four notices of violation were issued, for violations that occurred in 1991. By 1997, only two of the cases were settled, one after an appeal, and one prior to the hearing (Renko, 1998). Under the VIP program, penalties are based solely on observer data. This causes a fundamental change in the relationship between fishermen and observers compared to using observer data aggregated at the fleet level to impose catch quotas. Because the data is the only evidence used to enforce penalties, the methods used by observers to sample hauls, including how sample hauls are se-
221 lected, the percentage of sampled hauls, the distribution of samples within a haul, and the minimum acceptable sample size became critical points for enforcement. In addition to using acceptable sampling methods, observers must adhere to seven regulatory elements, which are (1) that NMFS will randomly predetermine the hauls to be sampled, (2) that the observer will take samples at random from throughout the haul, (3) that the observer will take samples prior to the sorting of the haul by the crew, (4) that the observer will sample a minimum of 100 kg of fish from each haul sampled, (5) that the observer, while at sea, will report the data to NMFS at least weekly for sampled hauls, (6) that upon request, the observer will allow the vessel operator to see all observed data, and (7) that the observer must sample at least 50% of a vessel’s total number of trawl hauls retrieved while the observer was aboard (Renko, 1998). Approved statistical methods for estimating bycatch rates from observer data, including 95% confidence limits, were developed. Enforcement action for vessels whose lower boundary on the 95% confidence limit of their bycatch rate exceeds the standard can only be taken after the observer’s sampling methods have found to be acceptable, the observer has adhered to the regulatory elements, and the observer’s scales have been tested for accuracy (Renko, 1998). Starting in 1993, bycatch rates extrapolated to the total haul have been posted by permit numbers and boat name on the Internet so the rest of the fleet can exert peer pressure on the ‘‘dirty’’ fishermen to lower high bycatch rates (NMFS, 2003c). In 1995, a private company called Sea State began contracting with vessels in the fleet to provide real time estimates of bycatch rates so that known ‘‘hot spots’’ could be avoided (NMFS, 1998). The observer’s reports are transmitted to the company, which then combines the reports, and returns aggregated information on bycatch rates by location to participating vessels. Whether the Sea State program has been effective at reducing bycatch has been debated. Developers of the program claim that the program has been very successful, particularly with reducing crab bycatch in the rock sole fishery, but reductions of halibut have been more questionable. In recent years, vessels that do not participate in the program have had lower halibut bycatch rates than vessels that do participate (Holland and Ginter, 2001), but this difference
could have been due to many factors, including targeting on different groundfish species with lower bycatch rates, and differences in fishing locations. An evaluation of the VIP program by Renko (1998) concluded that the program was ineffective at reducing bycatch or changing the behavior of fishermen. Problems included the lack of enforcement, the minor nature of the penalties, which are well within the cost of doing business, the lack of complete coverage on vessels less than 125 ft in length, the length of time between the offense and any resolution, and the fact that the fishermen can influence five out of the seven regulatory elements concerning sampling that are necessary for enforcement. The regulatory elements that fishermen can influence include observers taking random samples from throughout the haul, taking samples prior to sorting by the crew, weekly reporting to NMFS, sampling a minimum of 100 kg of fish from each sampled haul, and observing 50% of the vessel’s total hauls while the observer is onboard. If any of these requirements are not met, or if the scales used by the observer are not accurate, regardless of the reason, then the observer data cannot be used for enforcement.
Case study: 3. Pacific halibut in the Canadian groundfish trawl fishery The British Columbia groundfish trawl fishery is the largest fishery by volume on Canada’s west coast, with annual landings of approximately 140,000 mt, worth an estimated $60–65 million (CAD). The fishery targets demersal fishes such as rockfishes (Sebastes spp.), and flatfishes (flounders, soles), mackerels (Scomber spp), and roundfishes such as greenlings (Hexagrammos spp.), lingcod (Ophiodon elongatus), Pacific cod, sculpins (Procottus spp.), and Pacific hake (Merluccius productus). The trawl fishery has existed since the 1940s, although it expanded rapidly in the 1960s because of foreign fishing fleets. Canada expanded its fisheries management zone to 200 miles in 1977, and Fisheries and Oceans Canada began managing the groundfish trawl fishery in 1979 with time and area closures, license limitations, TACs and trip limits (Fisheries and Oceans Canada, 2003). In 1997, the Canadian government began an Individual Vessel Quota system to manage the groundfish trawl fishery, and this
222 system now encompasses 25 species in 55 speciesarea groups. In 1999, the groundfish trawl fleet consisted of 142 licensed vessels, of which 88 reported landings (Fisheries and Oceans Canada, 2003), although by 2000, there were only 70 active vessels (Fisheries and Oceans Canada, 2000). As with the US groundfish trawl fisheries, Pacific halibut bycatch has been a problem in the British Columbia groundfish trawl fishery, but Canada has been very aggressive in reducing halibut bycatch in this fishery. Starting in 1995, bycatch quotas by area were instituted in the groundfish trawl fleet in areas with the highest bycatch rates. The bycatch quota was reached on October 1, 1995, and the groundfish trawl fishery was shut down for that year. Bycatch caps were implemented in additional areas in 1996 and 1997. In 1996, Canada instituted an individual vessel bycatch quota (IVBQ) for its trawl fleet, which helped reduce total fleet bycatch from 681 mt in 1995 to 140 mt in 1996. Vessels could opt to be part of the IVBQ program (Option A), which required them to pay for 100% observer coverage. More than 90% of the fleet carried observers in 1996 (IPHC, 1997). Observers monitored 1095 trips and observed 21,312 tows in 1996 (IPHC, 1997). Another 27 vessels chose not to participate in the program, opting for more restrictive landing requirements and only 15 days of observer coverage per year (Option B, IPHC, 1996). Option B vessels were required to stop fishing when the fleet bycatch cap was reached, they had caps on their target species, and all landings were monitored. An additional option was available for small vessels that fished only in inside waters in the Strait of Georgia, where they were required to pay for contract dockside observers. Individual bycatch quotas were obtained by dividing the fleet quota by the number of vessels in the program in each area, and were administered by trimester. When a vessel’s IVBQ was reached in a specific area during a trimester, the vessel was required to stop fishing in that area until the next trimester, although it could continue fishing in another area if additional bycatch quota remained in that area. Pacific halibut mortality in Canadian groundfish trawls has continued to decline, with less than 120 mt caught annually in 1998–2000 (IPHC 1996–2001). While the large drop in overall bycatch has been credited mostly to the accountability by individual vessels afforded by the IVBQ, other management mea-
sures that were not directed at halibut mortality have also played a role, including requirements for larger mesh sizes, and fishery closures to prevent overfishing of target species (IPHC 1998b).
Case study: 4. New Zealand multi-species fisheries Since 1986, New Zealand has managed most of its fisheries through individual transferable quotas, a system called the quota management system, or QMS. Initially, 161 stocks of 28 species or species groups were brought into the QMS, but more species have been added since that time. The system consists of the Total Allowable Catch, which includes commercial, recreational, and Maori (native) fisheries, and the Total Allowable Commercial Catch (TACC), which is the commercial quota only. In the New Zealand multi-species trawl fisheries, 5–10 ITQ species can be caught together (Boyd and Dewees, 1992). Unlike bycatch management in other countries, under QMS there is no requirement that fishing for a target species stop fishing when the quota of a bycatch species is reached (Annala, 1996), except for the catch of protected species like marine mammals and seabirds. Bycatch of commercial species is managed by catch balancing, or finding quota to cover the catch (Peacey, 2002). Between 1986 and 2001, fishers were required to have ITQ to cover all the QMS species in their catch, or to have non-QMS species listed on their fishing permit before they went fishing (Bess, 2002; Peacey, 2002). However, there was a loophole that a reasonable defense for catching a species without quota or a species not listed on the permit was if the taking of that species was an inevitable consequence of catching the target species; in other words, bycatch. Fishers had to cover their QMS catch in retrospect by using up to 10% uncaught quota from the previous year, borrowing up to 10% quota from the following year, surrendering the catch to the government, buying or leasing ITQ from another fisher by the end of the year, fishing ‘on behalf’ of another quota holder, trading off bycatch of one fish stock against the ITQ of another fish stock taken in the same fishery, or paying a fee called a ‘‘deemed value’’ (Peacey, 2002). Small quota holders had trouble buying quota to match their catch in the early days of the
223 QMS because it was much easier to sell than buy, particularly near the end of the season, so the government allowed the bycatch trade-off scheme (Boyd and Dewees, 1992). Although the rules regarding bycatch trade-offs were fairly restrictive, some fishers used the trade-off system to target species for which they had no ITQ (Peacey, 2002). The deemed value was a price set for each kg of bycatch in excess of ITQ, which could be refunded if the fisherman found quota to cover the catch. The purpose of the deemed value was to balance two competing purposes: it had to be low enough to act as an incentive for fishermen to land bycatch rather than discard it, but high enough to discourage fishermen from catching species for which they had no quota (Peacey, 2002). NonQMS species must be discarded at sea (Bess, 2002). During the first two years of the QMS, 15 TACs were exceeded out of 160 in 1986/87 (9% of stocks), seven of which were due to bycatch in trawl fisheries, and 33 were exceeded in 1987/88 (20%), 17 due to bycatch in trawl fisheries (Peacey, 2002). In 1987/88, the average overrun was 18% over TACC, while the maximum was 74% (Boyd and Dewees, 1992). The number of overruns decreased during the early 1990s (Annala, 1996), with 17% of the stocks exceeding the TACC in 1991/92, the majority of those by a small amount (Peacey, 2002). In 1993/94, only 22 of 179 TACS (12%) were overcaught, leading scientists to believe that changes in fisherman behavior as they gained experience with the QMS and ‘‘fine-tuning’’ the quotas in relation to the catch were successful at reducing bycatch (Annala, 1996). However, by 2000/01, overages occurred in 27% of the 240 stocks in the QMS, and overruns were much greater than previously (Peacey, 2002). Reasons for these overruns may have been that the new species brought into the QMS were ones for which biological and catch information was lacking, leading fishery managers to set the TAC too low (Peacey, 2002). Under the catch-balancing system, there were persistent overruns in some fishstocks such as SNA2 snapper, which is caught both as a target species with longline gear, and as a bycatch species in trawl gear. The deemed value was not enough of a disincentive to trawling for snapper, and overages were as large as 50% in 1999/2000 and 2000/01. These problems caused the catch-balancing system to be redesigned in 2001 (Peacey, 2002).
Under the new catch-balancing system, the ITQ was redefined to be the right to receive the annual share of the TACC, while the actual quota became the annual catch entitlement, or ACE, which is based on the ITQ. Fishers can no longer lease ITQ, they can only use or buy ACE, and this can be done before or after fishing. Deemed values are now the only deterrents to fishermen taking catch that they cannot cover with ACE. If deemed values are not paid, the fishing permit is suspended, and fishing without a permit is a criminal offense. Misreporting of catch is also a criminal offense (Peacey, 2002). If deemed values are inadequate to restrict the catch to the TACC, then an overfishing threshold can now be set for a fish stock. This works on an individual rather than a fleet basis – if a fisherman’s catch exceeds his ACE by more than the overfishing threshold, he can be excluded from the fishery. The deemed value, as the primary deterrent to bycatch and overfishing, is now set at a level to encourage fishers to cover their catches with ACE. Part of the deemed value is refundable, and is paid by the end of the month, and part is non-refundable, and is paid by end of the year. Deemed values can be adjusted, and can also be set on a sliding scale based on the amount of overage. The idea is to make the costs of fishing without ACE greater than any profit that might be realized. Initial results from the SNA2 snapper fishery, which was consistently overfished under the old catch-balancing system, indicate that the new program is working (Peacey, 2002). The catch-balancing program, while solving some of the problems with fishery management in New Zealand, has not adequately addressed bycatch issues (Meister, 1999). Bycatch of commercial non-QMS species is still a problem, as is bycatch of species that have no commercial value. Fishers are currently unable to add non-QMS commercial species to their permits because of a moratorium on permits, and the ‘‘bycatch exemption’’ for non-QMS species expires in September 2004. New Zealand plans to bring 50 more species under the QMS system in 2004, so that additional species will be covered by the catch-balancing program (Bess, 2002). However, ITQs are not designed to preserve biodiversity, so bycatch of noncommercial species, such as invertebrate species on seamounts that are caught as bycatch in the orange roughy fishery, has been relatively ignored (Smith
224 undated). The Ministry of Fisheries, recognizing that the QMS system has not dealt effectively with non-quota species, has written a draft proposal for managing the environmental effects of fishing (New Zealand Ministry of Fisheries, 2003b). The plan proposes to (1) classify coastal marine species, particularly associated or dependent species, based on population viability, (2) set standards to maintain all species above the long term viability level, and (3) institute fisheries management practices to consider risks and to demonstrate that fishery effects on associated and dependent species are within acceptable limits.
Discussion Based on the bycatch quota experiences in different fisheries around the world, elements of successful bycatch quota programs include: (1) individual accountability, in the form of individual bycatch quotas or IBQs, (2) 100% observer coverage, (3) relatively small, manageable fleets, (4) limited landing ports that can be readily monitored, particularly if observer coverage is less than 100%, (5) reliable enforcement, (6) penalties that are true disincentives, and (7) some flexibility in the system for fishermen to have alternatives to manage their bycatch. IBQs are much more effective at reducing bycatch than fleet bycatch quotas. Fleet bycatch quotas induce fishermen to fish as quickly as possible so they can make their profit before the bycatch quota is reached (even if the target fishery is managed under an ITQ system), and they reward ‘‘bad’’ behavior because the fleet bears the cost of high bycatch rates while individuals reap the benefits of fishing without regard to consequences. IBQs have a higher chance of success because individual are accountable for their own fishing practices and incur both the benefits and costs of high bycatch rates. Under any quota system, the self-reporting of bycatch rates is not reliable, so complete observer coverage is essential. Without complete observer coverage, much of the data will have to be estimated or interpolated, making enforcement difficult if not impossible, as shown with the New Zealand sea lion take in the 2002/03 arrow squid fishery. Small manageable fleets and limited landing ports are necessary so that observation and enforcement
programs are practicable and affordable. Problems with enforcement increase in direct proportion to the geographic extent of the fishery, the number of fishing units, and the number of landing points (NRC, 1999). In addition, the larger the fleet or the territory that must be covered, the more difficult and expensive observation and enforcement becomes. Management agencies also have to have the money, personnel, and political will to make enforcement a priority; if there is no enforcement, there will be little compliance. In addition to enforcement, penalties must be consistent, unavoidable, swift, and more costly than the benefits gained. The US has shown little inclination to support harsh disincentives for individuals, as shown by the difference in the fines recommended by the North Pacific Council in the Alaska VIP program compared to those instituted by the NOAA General Counsel. Without true disincentives, either financial or fishery-based, quotas of any sort will be useless at controlling bycatch. Finally, fishermen must have alternatives, for example, multiple target species where fishermen can switch targets to lower bycatch rates, stratification of bycatch and target species in time or space so that fishing can be moved or delayed until bycatch conditions are more favorable, or flexible quota trading, that allows fishers to manage their bycatch over the long term such as the course of a season or year. Fisheries with unpredictable bycatch, where bycatch largely overlaps the target species in time and space, where bycatch of a particular species is rare, and where fishermen have little control over bycatch are unlikely to be successful under quota management because the only way that fishermen can avoid bycatch is to stop fishing. In these instances, gear modification to increase selectivity or effort reductions may be the best solutions to bycatch. The shrimp trawl fishery in the GOM as it is prosecuted today has many characteristics that make bycatch reduction by quotas, even IBQs, unlikely to succeed. These characteristics are related to (1) the size, extent, and manageability of the fleet, (2) the logistics of shrimp trawling, (3) the characteristics of the fishery and the bycatch, and (4) the statistical estimation of total bycatch. First, obtaining complete mandatory observer coverage on the GOM shrimp trawl fleet will be extremely challenging due to the size of the fleet, its spatial extent, and the historic lack of restric-
225 tive management. The fishery is huge, with an estimated 20,000 boats and vessels participating (NMFS, 1998). An estimated 2800 permitted vessels work in the offshore areas where the bycatch of red snapper is highest. Recreational fishermen in some areas can also use trawl gear to catch shrimp for personal use, and they also contribute to the bycatch problem, although their exact numbers are unknown (Wallace and Robinson, 1994). Recent economic difficulties in the fishery may have reduced the fleet size by some amount, but this reduction may have been offset by the availability of relief funds. The spatial extent of the fleet is also huge, from Florida to the Texas/ Mexico border, encompassing 1631 miles of coastline and 186,200 square nautical miles of ocean in the EEZ. Ports and landings are spread throughout the region, making both observation and enforcement very complicated. Because the shrimp stocks have never been recruitment overfished, no TAC is set, and there is currently no mandatory observation program, no effort limitations such as limited entry, or limits on the amount of gear permitted. Fishermen have only recently been required to apply for a permit to fish in federal waters. The major limitations in the fishery are time and area closures to prevent growth overfishing, and the requirements for TEDs and BRDs. TED requirements in particular were an extremely bitter and contentious issue in this fishery. This history of almost no restrictive management and the aftereffects of the historical problems with TED regulations may make it difficult to enlist cooperation from the fishing community for IBQs and for mandatory, complete observer coverage. The primary reason that fleet size would have to be reduced before quotas could be implemented is that obtaining complete observer coverage on a fleet this large would be prohibitively expensive. The voluntary observer program from 1992 to 1997, which cost about $1000 per sea day observed (J. Nance, NMFS, pers. comm.), covered less than 1% of the estimated effort. The Alaskan groundfish fishery observer program, which covers a fleet of less than 250 vessels, costs over $8 million annually, paid for by industry and supported by ‘‘pass through’’ funding from various sources (NMFS, 1998). Even if the GOM shrimp fleet were reduced by 50%, the number of observers and the cost of a mandatory observa-
tion program would be enormous. Also, the size of participating boats would have to be considered. Although offshore vessels are often larger than inshore boats, many of the shrimp boats are small and stay out for long periods of time. It may not be possible to take observers on the smaller boats. Logistically, observations in shrimp trawl fisheries are much more complicated than observations in the groundfish trawls, due to the smaller mesh sizes (1.5–1.75 in. or 3.8–4.5 cm in the GOM versus 5.5–8 in. or 14–20.3 cm in the North Pacific), the larger number of species caught, and the small size of individuals retained in the nets. In the North Pacific, fishermen tow one net. Individuals caught are generally over 300 mm in length and weigh an average of 0.5 kg, making the required sample of 100 kg equivalent to about 200 individuals. In the GOM, individuals caught in shrimp trawls are usually less than 150 mm in length and weigh an average of 0.02 kg. In the volunteer observer program, observers sampled 12 kg per hour towed and sampled only one of the two to four nets (NMFS 1992a,b). Since tows typically last 4–12 h, samples generally weighed about 48–144 kg, which is equivalent to 2300–7000 individuals sampled per net. Vessels in the North Pacific are typically either catcher boats that deliver to factory ships for processing or catcher/processors, so the total weight of the net is known to within ounces, making the expansion of the sample to the total net by weight a fairly easy calculation. In the shrimp trawl fishery, the total net is never weighed by the fisherman because the cod end is emptied onto the deck or culling tray and the shrimp are sorted and processed (heads removed) by hand. Observers weigh the total net, usually by shoveling the catch into baskets, which are then weighed individually on a hanging scale. Without an accurate measure of total weight, expansion of the sampled bycatch to the total net is questionable. In addition, if only one net is sampled, there is an assumption that the catch of the other nets is the same in terms of weight, species, and numbers, an assumption that is usually violated. Another problem with sampling methods in GOM shrimp trawls is the randomness of the sample. Based on the NMFS protocol, observers are required to mix the catch with a shovel to ensure a random sample, but this is sometimes difficult due to the weight of the catch,
226 the position of the culling tray, the size of the boat, or weather conditions. In addition, some species such as crabs may redistribute themselves after the catch is mixed by simply walking away, making it difficult to get a truly random sample. Therefore, while a procedure such as the NMFS protocol produces bycatch estimates that, when summed over the fleet, are reasonable for science and management, the uncertainty of the estimates may make legal enforcement of quotas on individual vessels extremely difficult. One option would be to pull out only red snapper from the total catch of all nets, but this can only done with the help of the fishermen and introduces the potential for fishermen to hide some of the catch. Technological solutions, such as using scales and data loggers that are attached to each net to weigh the total catch, have potential to solve some of the problems such as measuring the total weight, but many logistical problems remain. The characteristics of the shrimp trawl fishery and the characteristics of the bycatch, particularly the bycatch of red snapper, make quota management of bycatch problematic. First, there is no flexibility in the fishery in terms of target species because there are no other potential target species in the bycatch. The individuals are too small or unmarketable. Other fisheries in the GOM are struggling with sustainability of fishing on the target species, so switching to another fishery is not a viable option. Flexibility in terms of fishing within a season might be possible if there is stratification of shrimp and the bycatch species. For total bycatch (all species combined), finding stratification between shrimp and bycatch will be difficult for several reasons. There are so many species in the bycatch that some species will always overlap with shrimp. Most of the bycatch species are widespread in the GOM and very mobile, making it difficult to separate the catches of shrimp and bycatch. Most fishermen already avoid bycatch as much as possible because bycatch makes sorting their nets harder and more timeconsuming, which can cost them money in lost time, extra crew or fuel. However, bycatch catch rates are still high. So, although IBQs would allow fishermen to find their own solutions to controlling total bycatch, fishermen may not be able to finetune their operations enough to significantly reduce total bycatch. Avoiding the bycatch of red snapper is also difficult, because bycatch of red
snapper is unpredictable and relatively infrequent, with an average catch rate for an individual fisherman of six snapper per hour (NMFS, 1998). There is a potential to use the data from the volunteer observer program or fishery-independent data to look for stratification in the catch of shrimp and snapper by time and area, but the coverage of these data sets is sparse both temporally and spatially. A real-time monitoring program like the Sea Star program used in Alaska would be extremely useful in this fishery to provide data on stratification. One method of providing flexibility would be to use tradable quotas under an IBQ system for overages of either total bycatch or red snapper bycatch. Another promising alternative to IBQs is a community or cooperative bycatch quota (CBQ), which is the type of system that was so successful with the Japanese fleet in the Alaska groundfish fishery. Under this system, quotas are allotted to a group or cooperative rather than an individual, which then allows for flexibility in fishing among the members of the group. Finally, many of the problems that were found in the Alaska groundfish fisheries will be apparent in the GOM shrimp trawl fishery as well. These include the problems inherent in using observer data for enforcement purposes, such as the ability of the fishermen to influence the data collection, and the fact that not all hauls can be observed so there will be some estimation of bycatch. Bycatch estimation has historically been a problem in this fishery, with much debate concerning the best methods to use to estimate total bycatch from a sample, and the effects of uncertainty and variability on the estimates (Ortiz et al., 2000; Diamond, 2003). In additional to problems that are specific to the shrimp trawl fishery, setting up an IBQ management system will involve the typical problems of quota management, such as (1) identifying the objectives, (2) quota allocation, (3) transfer and accumulation policies, (4) setting TAC, (5) setting penalties, and (6) evaluating the program. There are three main questions that need to be asked when identifying the goals of a quota management program for the GOM shrimp trawl fishery. First, is the goal of the program to control the bycatch of red snapper only, or all bycatch species? If the goal only involves bycatch of red snapper, then only the offshore vessels need to be observed. Observations will also be much simpler because it is easier to select red snapper out of all nets than
227 to sample the nets for total bycatch. However, this would be an incredible waste of potential datagathering capabilities, and assumes that other species are unimportant ecologically as well as economically. An observer program just for red snapper would probably cost exponentially more per fish than red snapper sell for commercially. The best idea may be to monitor several of the most vulnerable or ecologically important bycatch species (however these are defined) to use as indicator species for the health of GOM communities, as well as monitoring the catch of red snapper. The second question is whether the goal of the quota program is to limit bycatch or to reduce bycatch. If the goal is to limit bycatch, then quotas should be set at a proportion of the estimated population. If the goal is to reduce bycatch, then quotas should be set at a specific weight or number and the bycatch will decrease as population rebuilds. Third, if the perceived problem with the bycatch is that it is wasted, should bycatch be landed? Ecosystem models may be the best tools to use to answer this question from an ecological perspective, but from an economic perspective, it is probably not sensible to fill the hold with lowvalue bycatch rather than high-value shrimp. Quota allocation refers to how the initial bycatch allocations would be set, for example, by an individual’s historical shrimp landings, historical effort in the fishery, or the size of the gear used. Transfer and accumulation policies involve limits on how much of the quota an individual or company could acquire. Additional issues would be whether the quota allocations would be owned or leased, which involves the level of rights the fishermen have in transferring quotas. Setting the initial TAC would also be a concern to fishermen. Penalties for overages should be specified, as well as penalties for activities such as high grading. Finally, questions about program evaluation should be specified in advance, including: how will the program be evaluated? What are the criteria for determining whether the program is successful? Clearly considering all of these factors in advance, in cooperation with the fishing community and other interested parties, can be the determining factor in whether IBQs work or not. In summary, the GOM shrimp trawl fishery is currently too large for IBQs to be practical, although IBQs or CBQs would be excellent strategies for a smaller fleet. However, a smaller fleet may
preclude the necessity for bycatch quotas in the GOM shrimp trawl fishery, since the reduction in effort combined with the current modifications to make trawl gear more selective may be all that is needed to reduce bycatch to desirable levels. At current levels of effort, BRDs could still be effective at reducing red snapper bycatch if the exact position of the BRD in the net was specified and only specific haulback procedures were allowed, but monitoring and enforcement would have to be increased significantly for these measures to be successful. Mobile closed areas might be beneficial at reducing bycatch of particular species like red snapper, but these would require real-time monitoring of bycatch rates, such as the system used in the Sea Star program in Alaska. Under this type of program, shrimpers or observers aboard shrimp boats would send in their bycatch rates and position after each tow, and the rates would be collated and plotted immediately. Areas of high bycatch rates or areas exceeding a certain bycatch threshold would be closed for a specified length of time. This system would work best if vessel monitoring systems were also required so that the closed areas could be enforced. Areas that had high bycatch rates over an extended time could be closed to shrimping permanently. However, in any management scenario, incentives and/or rigorously enforced disincentives are the key to successful bycatch reduction.
Acknowledgements I would like to thank Pam Baker and Environmental Defense for funding this project, Todd Neahr for his hard work in the library, and Kari Dupler and Erica Jennings for their editorial skills. Jim Nance, Paul Starr and David Witherell gave me lots of their time and helpful advice. Two anonymous reviewers improved the paper with helpful comments.
References Adkins, G. (1993) A comprehensive assessment of bycatch in the Louisiana shrimp fishery. Louisiana Department of Wildlife and Fisheries, Marine Fisheries Division, Technical Bulletin No. 42.
228 Ainley, D.G., DeGange, A.R., Jones, L.L. and Beach, R.J. (1981) Mortality of seabirds in high-seas salmon gill nets. Fish. Bull. 79(4), 800–806. Alverson, D.L., Freeberg, M.H., Murawski, S.A. and Pope, J.G. (1994) A global assessment of fisheries bycatch and discards. Food and Agriculture Organization Fisheries Technical Paper No. 339, 233 pp. Anderson, W.W. (1968) Fishes taken during shrimp trawling along the South Atlantic coast of the United States, 1931– 1935. Bureau of Commercial Fisheries Biological Laboratory, Contribution No. 92. United States Fish and Wildlife Service, Special Scientific Report–Fisheries No. 570, Brunswick, GA, 60 pp. Anderson, W.W. and Gehringer, J.W. (1965) Biological–statistical census of the species entering fisheries in the Cape Canaveral area. U.S. Fish and Wildlife Service Special Scientific Report – Fisheries No. 514, 79 pp. Annala, J.H. (1996) New Zealand’s ITQ system: have the first eight years been a success or a failure? Rev. Fish Biol. Fisher. 6, 43–62. Arreguin-Sanchez, F. and Castro-Melendez, R.G. (2000) On the interdependence of sequential fisheries: the brown shrimp, Farfantepenaeus aztecus, fisheries in the northwestern Gulf of Mexico. Crustaceana 73(Part 3), 333–343. Arreguin-Sanchez, F., Zetina-Rejon, M., ManickchandHelleman, S., Ramirez-Rodriguiz, M. and Vidal, L. (2004) Simulated response to harvesting strategies in an exploited ecosystem in the southwestern Gulf of Mexico. Ecol. Model. 172(2–4), 421–432. Bahen, J.J., Murray, J.D. and Rulifson, R.A. (1993). Development and evaluation of finfish separator device and TED combination to reduce bycatch in the shrimp fishery. Final Report to MARFIN, Award No. NA17FD0101-01. University of North Carolina Sea Grant Program, North Carolina State University, Raleigh, NC. Baltz, D.M. (1993) Patterns in the distribution and abundance of fishes and macroinvertebrates in a Louisiana marsh: shrimp bycatch in the inshore, fishery-independent trawl samples. Final Report to MARFIN, Award No. NA17FF0263-01. Louisiana State University, Coastal Fisheries Institute, Baton Rouge, LA. Baum, J.K., Meeuwig, J.J. and Vincent, A.C.J. (2003) Bycatch of lined seahorses (Hippocampus erectus) in a Gulf of Mexico shrimp trawl fishery. Fish. Bull. 101(4), 721–731. Bearden, C., Low, R., Rhodes, R., Van Dolan, R., Wenner, C., Wenner, E. and Whitaker, D. (1985) A review and analysis of commercial shrimp trawling in the sounds and bays of South Carolina. South Carolina Marine Resources Center, Technical Report No. 61, 51 pp. Berry, R.J. and Harvey, J.B. (1964) Mesh selectivity studies. U.S. Department of Interior, U.S. Fish and Wildlife Service, Bureau of Commercial Fisheries Biological Laboratory, Galveston, TX. Berry, R. J., and Benton, R.C. (1969) Discarding practices in the Gulf of Mexico shrimp fishery. Food and Agricultural Organization Fisheries Report No. 57(3), pp. 983–999. Bess, R. (2002) Expanding New Zealand’s quota management system. Paper presented at International Institute of Fisheries Economics and Trade (IIFET) Conference, August 19–22, 2002, Wellington, New Zealand. [cited 2004 October 20].
Available from: http://www.fish.govt.nz/current/press/spconfpap.htm. Boyd, R.O. and Dewees, C.M. (1992) Putting theory into practice: individual transferable quotas in New Zealand’s fisheries. Soc. Natur. Resour. 5, 179–198. Branstetter, S. (1997) Bycatch and its reduction in the Gulf of Mexico and South Atlantic shrimp fisheries. Gulf and South Atlantic Fisheries Development Foundation, Inc., Suite 997, Lincoln Center, 5401 West Kennedy Boulevard, Tampa, Florida, 27 pp. + tables and figures. Breen, P.A., Hilborn, R., Maunder, M.N. and Kim, S.W. (2003) Effects of alternative control rules on the conflict between a fishery and a threatened sea lion (Phocarctos hookeri). Can. J. Fish. Aquatic Sci. 60(5), 527–541. Browder, J.A. (1983) A simulation model of a near-shore marine ecosystem of the north-central Gulf of Mexico. In: Turgeon, K.W. (ed.), Marine Ecosystem Modelling – Proceedings from a workshop help April 6–8, 1982. Frederick, MD. NOAA, Washington, DC, pp. 179–222. Browder, J.A. (1992) An application of the ecosystem approach to fishery management research in the Gulf of Mexico. In: Proceedings of the shrimp trawl bycatch workshop, November 22–23, 1991. St. Petersburg, FL. Center for Marine Conservation, Washington, DC, pp. 8–10. Browder, J. A. (1993) A pilot model of the Gulf of Mexico continental shelf. In: Christensen, V. and Pauly, D. (eds.), Trophic Models of Aquatic Ecosystems. ICLARM Conference Proceedings No. 26, pp. 279–284. Brown, B.E., Browder, J.A., Powers, J. and Goodyear, C.P. (1991) Biomass, yield models and management strategies for the Gulf of Mexico ecosystem. In: Sherman, K. (ed.), Biomass, Yield Models and Management Strategies. AAAS Publication, Westview Press, Boulder, CO, pp. 125–163. Brown, J. and McCoy, E.G. (1969) A review of the North Carolina scrap fishery. North Carolina Department of Conservation and Development, Division of Commercial and Sports Fisheries, Raleigh, NC, Information Series No. 1, 12 pp. Bryan, C.E., Cody, T.J. and Matlock, G.C. (1982) Organisms captured by the commercial shrimp fleet on the Texas brown shrimp grounds. Texas Parks and Wildlife Department, Technical Series No. 31, 26 pp. Burchfield, P.M. and Pen˜a, L.J. (2003) A sea turtle stranding network as part of the Mexico/United States of America population restoration project for the Kemp’s ridley sea turtle. Final report to the National Marine Fisheries Service in partial fulfillment of service order #WC133F-02-SE-0290 [cited 2004 October 19]. Available from: http://www.sefsc.noaa.gov/PDFdocs/CR_Burchfield_Pena_Strandings_rep ort_2003.pdf Burgess, G.H. and Snyder, D.B. (1993) Fish bycatch from inshore shrimp fisheries in Florida. In: Proceedings of the International Conference on Shrimp Bycatch, May 24–27, 1992. Lake Buena Vista, Florida, Southeastern Fisheries Association, Tallahassee, FL, pp. 83–84. Burridge, C.Y. and Robbins, J.B. (2000) Benefits of statistical blocking techniques in the design of gear evaluation trials: introducing the Latin Square design. Fish. Res. 47(1), 69–79. Carter, N. and Colura, R. (1996) Comparison of survival of bycatch associated with bait shrimping in three Texas
229 estuarine areas. Texas Parks and Wildlife Department, Perry R. Bass Marine Fisheries Research Station, Palacios, TX. Castro-Gonzales, M.I., Barrita, J.L.S., Silva,M.E.J., Benavides, S.M. and Romo, F.P.G. (1998) Chemical composition of shrimp by-catch fauna in Veracruz (Gulf of Mexico). Rev. Biol. Trop. 46(2), 249–256. Chittenden, M.E. Jr. and McEachran, J.D. (1976) Composition, ecology, and dynamics of demersal fish communities on the northwestern Gulf of Mexico continental shelf, with a similar synopsis for the entire Gulf. Final Report to Texas Sea Grant (TAMU-SG-76-208). Texas A&M University, College Station, TX. Christian, P.A. and Harrington, D.L. (1987) Loggerhead turtle, finfish, and shrimp retention studies on four turtle excluder devices (TEDs). In: Proceedings of the nongame and endangered wildlife symposium, September 8–10, Georgia Dept. of Natural Resources, Social Circle, GA, pp. 114–127. Christian, P., Harrington, D.L., Amos, D.R., Overman, R.G., Parker, L.G. and Rivers, J.B. (1993) Final report on the reduction of finfish capture in South Atlantic shrimp trawls. Final report on Saltonstall-Kennedy Grant Program Project NA27FD0070-01, December 1993. University of Georgia Marine Extension Service, Brunswick, GA, 81 pp. Coale, J.S. (1992) Changes in bycatch using skimmer trawl in the North Carolina shrimp fishery. MS Thesis. East Carolina University, Dept. of Biology, Greenville, NC. Coale, J.S., Rulifson, R.A., Murray, J.D. and Hines, R. (1994) Comparisons of shrimp catch and bycatch between a skimmer trawl and an otter trawl in the North Carolina inshore shrimp fishery. North Am. J. Fish. Manage. 14, 751–768. Coleman, F.C., Koenig, C.C. and Herrnkind, W.F. (1991) Survey of Florida inshore trawling bycatch and preliminary tests of by-catch reduction devices. First Annual Report to the Florida Department of Natural Resources, National Marine Fisheries Service MARFIN Grant, Number NA37FF0051. Institute for Fishery Resource Ecology, Florida State University, Tallahassee, FL, 25 pp. Coleman, F.C., Koenig, C.C. and Herrnkind, W.F. (1992) Survey of Florida inshore trawling bycatch and preliminary tests of by-catch reduction devices. Second Annual Report to the Florida Department of Natural Resources, National Marine Fisheries Service MARFIN Grant, Number NA37FF0051. Institute for Fishery Resource Ecology, Florida State University, Tallahassee, FL, 21 pp. Colura, R. and Bumguardner, B.W. (2001) Effect of the saltbox catch–bycatch separation procedure, as used by the Texas shrimp industry, on short-term survival of bycatch. Fish. Bull. 99(3), 399–409. Condrey, R.D. and Fuller, D. (1992) The US Gulf shrimp fishery. In: Glanz, M.H. (ed.) Climate Variability, Climate Change, and Fisheries. Cambridge University Press, Cambridge, UK, pp. 89–119. Cortes, E. (1995) Demographic analysis of the Atlantic sharpnose shark, Rhizoprionodon terraenovae, in the Gulf of Mexico. Fish. Bull. 93(1), 57–66. Crouse, D.T., Crowder, L.B. and Caswell, H. (1987) A stagebased population model for loggerhead sea turtles and implications for conservation. Ecology 68(5), 1412– 1423. Cushing, D.H. (1984) Do discards affect the production of shrimps in the Gulf of Mexico? In: Gulland, J.S. and
Rothschild, B.J. (eds.) Penaeid shrimps – their biology and management. Selected papers presented at the Workshop on the Scientific Basis for the Management of Penaeid Shrimp, Key West, FL, November 1981. Fishing News Books, Ltd., Farnham, Surrey, UK, pp. 254–258. Diamond, S.L. (1999) The population-level impacts of shrimp trawl bycatch on Atlantic croaker. Ph.D. dissertation, North Carolina State University, Raleigh, NC. Diamond, S.L. (2003) Estimation of bycatch in shrimp trawl fisheries: a comparison of estimation methods using field data and simulated data. Fish. Bull. 101(3), 484–500. Diamond, S.L. and Hanan, D.A. (1986) An estimate of harbor porpoise mortality in California set net fisheries, April 1, 1983 through March 31, 1984. National Marine Fisheries Service Administrative Report SWR-86-15. Southwest Fisheries Science Center, La Jolla, CA, 40 pp. Diamond, S.L., Crowder, L.B. and Cowell, L.G. (1999) Catch and bycatch: the qualitative effects of fisheries on population vital rates of Atlantic croaker. Trans. Am. Fish. Soc. 128, 1085–1105. Diamond, S.L., Cowell, L.G. and Crowder, L.B. (2000) Population impacts of shrimp trawl bycatch on Atlantic croaker. Can. J. Fish. Aquat. Sci 57, 2010–2021. Ehrhardt, N. (1996) Impacts of TED and BRD designs on overall finfish bycatch reduction and their relative effects on management strategies adopted in directed finfish fisheries. University of Miami – Rosentiel School of Marine and Atmospheric Sciences, Virginia Beach Drive, Miami, FL. Engaas, A., Foster, D., Hataway, B.D., Watson, J.W. and Workman, I. (1999) The behavioral response of juvenile red snapper (Lutjanus campechanus) to shrimp trawls that utilize water flow modifications to induce escapement. Mar. Technol. Soc. J. 33(2), 43–50. Fahy, W.E. (1965a) Report of trash fish study in North Carolina in 1962. North Carolina Department of Conservation and Development, Division of Commercial and Sports Fisheries, Raleigh, NC, Special Scientific Report No. 5, 20 pp. Fahy, W.E. (1965b) Report of trash fish study in North Carolina in 1964. North Carolina Department of Conservation and Development, Division of Commercial and Sports Fisheries, Raleigh, NC, Special Scientific Report No. 7, 13 pp. Fahy, W.E. (1966) Species composition of the North Carolina industrial fish fishery. Commer. Fish. Rev. 28(7), 1–8. Federal Register (1987) Sea turtle conservation; shrimp trawling requirements. 50 CFR Parts 272, 222, 227 and 52 FR 24244. June 27, 1987, Washington, DC. Federal Register (1998) Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Shrimp Fishery of the Gulf of Mexico; Amendment 9. 63(71): 970523122-8022-02. April 14, 1998, Washington, DC. Federal Register (2002) Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Shrimp Fishery of the Gulf of Mexico; Amendment 11. 67(152): 011018254-2153-02. August 7, 2002, Washington, DC. Federal Register (2003a) Endangered and threatened wildlife; sea turtle conservation requirements. 68(35):000320077-230203. February 21, 2003, Washington, DC. Federal Register (2003b) Notice of decision on petition for rulemaking on bycatch. 68(47): 030224043-3043-01. March 11, 2003, Washington, DC.
230 Federal Register (2003c) Financial assistance for fisheries disasters. 68(102): 030506116-3116-01. May 28, 2003, Washington, DC. Fertl, D. (1994) Occurrence, movements, and behavior of bottlenose dolphins (Tursiops truncatus) in association with the shrimp fishery in Galveston Bay, Texas. MS Thesis. Texas A&M University, College Station, TX. Fisher R.B. (1992) Introduction to bycatch. In: Schoning, R.W., Jacobson, R.W., Alverson, D.L., Gentle, T.H. and Auyong, J. (eds.), Proceedings of National Industry Bycatch Workshop February 4–6, 1992. Newport Oregon. Natural Resources Consultants, Seattle, WA, pp. 5–10. Fisheries and Oceans Canada (2000) News release: Groundfish trawl fishery opens. NR-PR-00-36E. 2000 April 28. Available from the internet URL: http://www.pac.dfo-mpo.gc.ca/ comm/pages/release/p-releas/2000/nr0036_e.htm. Fisheries and Oceans Canada (2003) Fish stocks of the Pacific Coast: online book. Available from: http://www-comm.pac.dfo-mpo.gc.ca/publications/speciesbook/groundfish/default_e. htm. Fisheries Statistics of the United States 1942–1977. US Fish and Wildlife Service, Bureau of Commercial Fisheries, Statistical Digest Numbers 36–71. Foster, D.G. and Scott-Denton, E. (2004) Status of bycatch reduction device performance and research in North–Central and Western Gulf of Mexico. Working paper to the Red Snapper Stock Assessment Data Workshop, April, 2004. Document No. SEDAR7-DW-38. Gulf of Mexico Fishery Management Council, The Commons at Rivergate, Tampa, FL. Fuls, B. (1995) Assessment of composition and magnitude of bycatch associated with the commercial shrimp trawling industry in central lower Texas coastal bays during the spring and fall Texas commercial bay-shrimp open seasons. Texas Parks and Wildlife Department, Corpus Christi, TX. Fuls, B. (2001) Evaluation of shrimp trawl bycatch reduction devices in Texas bays. Texas Parks and Wildlife Department, Corpus Christi, TX. Gallaway, B.J., Cole, J.G., Martin, L.R., Nance, J.M. and Longnecker, M. (2003a) An evaluation of an electronic logbook as a more accurate method of estimating spatial patterns of trawling effort and bycatch in the Gulf of Mexico shrimp fishery. North Am. J. Fish Manage. 23(3), 787–809. Gallaway, B.J., Cole, J.G., Martin, L.R., Nance, J.M. and Longnecker, M. (2003b) Description of a simple electronic logbook designed to measure effort in the Gulf of Mexico shrimp fishery. North Am. J. Fish. Manage. 23(2), 581–589. Gearhart, J. (1996) Introduction of large mesh webbing in the belly of a traditional shrimp trawl to reduce bycatch in inshore waters. MS Thesis. Eastern Carolina University, Greenville, NC. Gilbert, J.R. and Wynne, K.M. (1984) Harbor seal populations and fisheries interactions with marine mammals in New England, 1984. Fourth Annual Report, contracts NA-80-FAC-00029 and NA-84-EA-C-0070. Submitted to the Northeast Fisheries Center, National Marine Fisheries Service, Woods Hole, MA, 15 pp. Goodyear, C.P. (1991) Sensitivity of shrimp-bycatch mortality estimates to natural mortality for red snapper. National Marine Fisheries Service, Southeast Fisheries Science
Center, Miami Laboratory, Virginia Beach Drive, Miami, FL. Goodyear, C.P. (1992) Red snappers in US waters of the Gulf of Mexico. Contribution MIA91/92-70. National Marine Fisheries Service, Southeast Fisheries Science Center, Miami Laboratory, Virginia Beach Drive, Miami, FL. Goodyear, C.P. (1994) Red snappers in US waters of the Gulf of Mexico. Contribution MIA93/94-63. National Marine Fisheries Service, Southeast Fisheries Science Center, Miami Laboratory, Virginia Beach Drive, Miami, FL. Goodyear, C.P. (1995) Red snapper in US waters of the Gulf of Mexico. Contribution: MIA-95/96-05. National Marine Fisheries Service, Southeast Fisheries Science Center, Miami Laboratory, Coastal Resources Division, Virginia Beach Drive, Miami, FL, 171 pp. Goodyear, C.P. and Phares, P. (1990) Status of red snapper stocks of the Gulf of Mexico, report for 1990. CRD 89/90-05. National Marine Fisheries Service, Southeast Fisheries Science Center, Miami Laboratory, Coastal Resources Division, Virginia Beach Drive, Miami, FL. Griffin, W. (2004) Discussion of days fished expansion in the Gulf of Mexico shrimp fishery. Working paper to the Red Snapper Stock Assessment Data Workshop, April, 2004. Document No. SEDAR7-DW-6. Gulf of Mexico Fishery Management Council, The Commons at Rivergate, Tampa, Florida. Griffin, W.L. and Shah, A.K. (1995) Estimation of standardized effort in the heterogeneous Gulf of Mexico shrimp fleet. MARFIN Final Report, Award Number NA37FF053. GSAFDF (Gulf and South Atlantic Fisheries Development Foundation) (1995) Continued observer coverage of the Gulf of Mexico and South Atlantic shrimp fisheries to characterize the catch and evaluate the efficiency of bycatch reduction devices. Final Report (Award NA47FM0131). Gulf and South Atlantic Fisheries Development Foundation, Tampa, FL 33609. GMFMC (Gulf of Mexico Fishery Management Council) (1980) Draft Fishery Management Plan for Groundfish in the Gulf of Mexico. Gulf of Mexico Fishery Management Council, The Commons at Rivergate, Tampa, FL. GMFMC (Gulf of Mexico Fishery Management Council) (2002) Red snapper rebuilding amendment scooping document. Gulf of Mexico Fishery Management Council, The Commons at Rivergate, Tampa, FL, Available from: http:// www.gulfcouncil.org/downloads/Red%20snapper%20 scoping%20document%208-21-02.pdf. Gunter, G. (1936) Studies of the destruction of marine fish by shrimp trawlers in Louisiana. La. Cons. Rev., La Dept. of Conservation, New Orleans, LA, Oct. 1936, pp. 18–24, 45–46. Gunter, G. (1956) Should fish and game fishes become more or less abundant as pressure increases in the trash fish fishery of the Gulf of Mexico? LA Dept. of Wildlife and Fisheries, New Orleans, LA, LA Conserv., 11, 14–15, 19. Gutherz, E.J. and Pellegrin, G.J. Jr. (1986) Report on snapper– grouper mortality by shrimp trawlers in the US Gulf of Mexico. Report to the Gulf of Mexico Fishery Management Council, The Commons at Rivergate, Tampa, FL. Gutherz, E.J. and Pellegrin, G.J. Jr. (1988) Estimate of the catch of red snapper, Lutjanus campechanus, by shrimp trawlers in the United States Gulf of Mexico. Mar. Fish. Rev. 59(1), 17–25.
231 Haby, M.G., Miget, R.J., Falconer, L.L. and Graham, G.L. (2003) A review of current conditions in the Texas shrimp industry, an examination of contributing factors, and suggestions for remaining competitive in the global shrimp market. TAMU-SG-03-701. Texas A&M Agricultural Research and Extension Center, Agnes St., Corpus Christi. Hall, M.A. (1996) On bycatches. Rev. Fish Biol. Fisher. 6, 319– 352. Hall, M.A., Alverson, D.L. and Metuzals, K.I. (2000) By-catch: problems and solutions. Mar. Pollut. Bull. 41(1–6), 204–219. Harrington, D.L. (1996) Finfish excluder devices in the South Atlantic shrimp fishery. In: Castro, K., Corey, T., DeAlteris, J. and Gagnon, C. (eds.), Proceedings of the East Coast Bycatch Conference, April 7–8, 1995, Newport, RI. Rhode Island Sea Grant, University of Rhode Island Bay Campus, Narragansett, RI. December 1996, pp. 91–94. Harris, P.J. and Dean, J.M. (1998) Characterization of king mackerel and Spanish mackerel bycatches of South Carolina shrimp trawlers. North Am. J. Fish. Manage. 18(2), 439–453. Heales, D.S., Brewer, D.T. and Wang, Y.G. (2000) Subsampling multi-species trawl catches from tropical northern Australia: does it matter which part of the catch is sampled? Fish. Res. 48(2), 117–126. Heales, D.S., Brewer, D.T. and Jones, P.N. (2003a) Subsampling trawl catches from vessels using seawater hoppers: are catch composition estimates biased. Fish. Res. 63(1), 13–120. Heales, D.S., Brewer, D.T., Wang, Y.G. and Jones, P.N. (2003b) Does the size of subsamples taken from multispecies trawl catches affect estimates of catch composition and abundance? Fish. Bull. 101(4), 790–799. Hensley, V.I. and Hensley, D.A. (1995) Fishes eaten by sooty terns and brown noddies in the Dry Tortugas, Florida. B. Mar. Sci. 56(3), 813–821. Higgins, E. and Pearson, J.C. (1927) Examination of the summer fisheries of Pamlico and Core Sounds, N.C., with special reference to the destruction of undersized fish and the protection of the gray trout, Cynosion regalis. Rep. to the US Commissioner of Fisheries for 1927. B.F. Doc. # 1019., US. Gov. Printing Office, Washington, DC. Hines, K.L., Rulifson, R.A. and Murray, J.D. (1999) Performance of low-profile skimmer trawls in the inshore shrimp fishery of North Carolina. North Am. J. Fish. Manage. 19(2), 569–580. Hoar, P., Hoey, J., Nance, J. and Nelson, C (eds.) (1992) A research plan addressing finfish bycatch in the Gulf of Mexico and South Atlantic Shrimp Fisheries. Gulf and South Atlantic Fisheries Development Foundation, Inc., Tampa, FL, 114 pp. Hoese, H.D. (1973) A trawl study of nearshore fishes and invertebrates of the Georgia coast. Contrib. Mar. Sci. 17, 63–98. Holland, B.F. Jr. (1989) Evaluation of certified trawl efficiency devices (TEDs) in North Carolina’s nearshore ocean. Completion Report Project 2-439-R. North Carolina Department of Natural Resources and Community Development, Division of Marine Fisheries, Morehead City, NC, 38 pp. Holland, D.S. and Ginter, J.J.C. (2001) Common property institutions in the Alaskan groundfish fisheries. Mar. Policy 25, 33–42. IPHC (International Pacific Halibut Commission) (1996) Annual Report, Seattle, WA, 64 pp. Available from:
http://www.iphc.washington.edu/halcom/pubs/annrep/AnnualReport96.pdf. IPHC (International Pacific Halibut Commission) (1997) Annual Report, Seattle, WA, 80 pp. Available from: http:// www.iphc.washington.edu/halcom/pubs/annrep/ar1997.pdf. IPHC (International Pacific Halibut Commission) (1998a) Annual Report, Seattle, WA, 80 pp. Available from: http:// www.iphc.washington.edu/halcom/pubs/annrep/ar1998.pdf. IPHC (International Pacific Halibut Commission) (1998b) The Pacific halibut: biology, fishery, and management. Technical Report No. 40, Seattle, WA, 64 pp. Available from: http://www.iphc.washington.edu/halcom/pubs/techrep/tech0040. pdf. IPHC (International Pacific Halibut Commission) (1999) Annual Report, Seattle, WA, 72 pp. Available from: http:// www.iphc.washington.edu/halcom/pubs/annrep/ar1999.pdf. IPHC (International Pacific Halibut Commission) (2000) Annual Report, Seattle, WA, 76 pp. Available from: http:// www.iphc.washington.edu/halcom/pubs/annrep/ar2000.pdf. IPHC (International Pacific Halibut Commission) (2001) Annual Report, Seattle, WA, 80 pp. Available from: http:// www.iphc.washington.edu/halcom/pubs/annrep/ar2001.pdf. Jones, B. (2004a) EBLUB small area estimation for red snapper bycatch from the Gulf of Mexico shrimp fleet. Working paper to the Red Snapper Stock Assessment Data Workshop, April, 2004. Document No. SEDAR7-DW-31. Gulf of Mexico Fishery Management Council, The Commons at Rivergate, Tampa, FL. Jones, B. (2004b) Spatial modeling of red snapper shrimp fleet bycatch in the Gulf of Mexico. Working paper to the Red Snapper Stock Assessment Data Workshop, April, 2004. Document No. SEDAR7-DW-32. Gulf of Mexico Fishery Management Council, The Commons at Rivergate, Tampa, FL. Jones, L.L. (1981) U.S. research on the incidental take of marine mammals by Japanese salmon mothership fishery: 1981 progress report (Document submitted to the Scientific Subcommittee of the Ad Hoc Committee on Marine Mammals, International North Pacific Fisheries Commission). National Marine Mammal Laboratory, Northwest and Alaska Fisheries Center, NMFS, Seattle, WA, 27 pp. Keiser, R.K. Jr. (1976) Species composition, magnitude and utilization of the incidental catch of the South Carolina shrimp fishery. Technical Report No. 16, South Carolina Marine Resources Center, Charleston, SC, 94 pp. Keiser, R.K. Jr. (1977) The incidental catch from commercial shrimp trawlers of the South Atlantic states. Technical Report No. 26, South Carolina Wildlife and Marine Resources Department, Charleston, SC, 38 pp. Knowlton, C.J. (1972) Fishes taken during commercial shrimping in Georgia’s close inshore ocean waters. Coastal Fisheries Office, Game and Fish Division, Department of Natural Resources, State of Georgia. Contribution Series No. 21, 42 pp. Latham, F.F. (1951) Evidence of fish loss due to shrimping in Pamlico Sound. Committee Report to Atlantic States Marine Fisheries Commission, November 1, 1951, 4 pp. (Appendix B) Lindner, M.J. (1936) A discussion of the shrimp trawl-fish problem. La. Conserv. Rev. 4, 12–17, 51. Logan, M. (2003) Marine mammals and the mistaken minister. Seafood New Zealand 11(4), 18–20.
232 Lupton, O. (1998) Certification of bycatch reduction devices in North Carolina. Report to the North Carolina Division of Marine Fisheries, Grant No. FEG-98-23. Pamlico County Schools, Bayboro, NC 28515, 24 pp. Lunz, G. R., McHugh, J.L., Roelofs, E.W., Tiller, R.E. and Atkinson, C.E. (1951) The destruction of small fish by the shrimp trawlers in Pamlico Sound, North Carolina. Report to the Chesapeake and South Atlantic Sections, Atlantic States Marine Fisheries Commission, November 1, 1951, 13 pp. + Appendices. Manley, B.F., Seyb, A. and Fletcher, D.J. (2002) Bycatch of sea lions (Phocarctos hookeri) in New Zealand fisheries, 1987/88 to 1995/96, and observer coverage. New Zealand Department of Conservation Science Internal Series 42. New Zealand Department of Conservation, Wellington, New Zealand, 21 pp. Available from: http://www.doc.govt.nz/Publications/ 004Science-and-Research/DOC-Science-Internal-Series/ PDF/DSIS42.pdf. Marquez Millan, R., Villanueva, O.A. and Burchfield, P.M. (1989) Nesting population and production of hatchlings of Kemp’s ridley sea turtle at Rancho Nuevo, Tamaulipas, Mexico. In: Proceedings of the First International Symposium on Kemp’s Ridley Sea Turtle Biology, Conservation, and Management, October 1–4, 1985, Galveston, TX. TAMU-SG-89-105. Texas A&M University Sea Grant Program. College Station, TX, pp. 16–19. Martinez, E.X., Nance, J.M., Zein-Eldin, Z.P., Davis, J., Rathmell, L. and Emiliani D.A. (1993) Trawling bycatch in the Galveston Bay system. Galveston Bay National Estuary Program, Webster, TX, GBNEP-34, 185 pp. Martinez, E.X., Nance, J.M. and Zimmerman, R.J. (1996) A model for assessment of ecological interactions among living marine resources in the Gulf of Mexico: implications for bycatch management and shrimp production. Report to the Gulf of Mexico Fishery Management Council, The Commons at Rivergate, Tampa, FL. Maunder, M.N., Starr, P.J. and Hilborn, R. (2000) A Bayesian analysis to estimate loss in squid catch due to the implementation of a sea lion population management plan. Mar. Mammal Sci. 16(2), 413–426. McKenna, S. (1996) Effectiveness of excluder devices on bycatch reduction and shrimp retention. In: Castro, K., Corey, T., DeAlteris, J. and Gagnon, C. (eds.), Proceedings of the East Coast Bycatch Conference, April 7–8, 1995, Newport, RI. Rhode Island Sea Grant, University of Rhode Island Bay Campus, Narragansett, RI, December 1996, pp. 106–112. McKenna, S.A., and Monoghan, J.P. Jr. (1991) Gear development to improve management of commercial fisheries in North Carolina. Saltonstall-Kennedy Award NA90AAHSK- 052; annual contract report to the Gulf and South Atlantic Fisheries Development Foundation (contract 43-01), Tampa, FL. McKenna, S. and Monaghan, J.P. Jr. (1993) Gear development to reduce bycatch in the North Carolina trawl fisheries. Department of Environment, Health, and Natural Resources, North Carolina Division of Marine Fisheries, Morehead City, NC, 59 pp. + Appendices. McKenna, S., Judy, G., Lewis, C. P. and Schoolfield, J. (1996) Evaluation of trawl efficiency devices/bycatch reduction devices in estuarine and nearshore waters of North Carolina. Completion Report for NOAA Award Number NA 47 FF0016, March 1996. North Carolina Division of
Marine Fisheries, Morehead City, NC, 39 pp. + tables and figures. Meister, A.D. (1999) The New Zealand experience with fishery management: lessons learned. Special Paper: Economy and Environment Program for Southeast Asia (EEPSEA), International Development Research Center, Ottowa, Canada. 13th EEPSEA Biannual Workshop, Singapore, November 1999, 25 pp. Available from: http://idrinfo.idrc.ca/archive/ corpdocs/118111/NewZealand.htm. Meyer, D.L., Fonseca, M.S., Murphey, P.L., McMichael, R.H., Byerly, M.M., LaCroix, M.M., Whitfield, P.E. and Thayer, G.W. (1999) Effects of live-bait shrimping on seagrass beds and fish bycatch in Tampa Bay, Florida. Fish. Bull. 97(1), 193–199. Morris, B. (1999) North Carolina bycatch reduction device certification. Report to the North Carolina Division of Marine Fisheries, Grant No. FEG-97-40. Pamlico County Schools, Bayboro, NC 28515, 30 pp. Murawski, S.A. and Finn, J.T. (1988) Biological bases for mixed-species fisheries: species co-distribution in relation to environmental and biotic variables. Can. J. Fish. Aquat. Sci. 45, 1720–1735. Murray, J.D., Bahen, J.J. and Rulifson, R.A. (1992) Management considerations for by-catch in the North Carolina and Southeast shrimp fishery. Fisheries 17(1), 21– 26. Murray, J.D., Diamond, S.L. and Bahen, J.J. (1994) A program to distribute and evaluate bycatch reduction devices in inshore waters of North Carolina. Final Report to MARFIN, Award Number NA37FF038-01, November 1994, University of North Carolina Sea Grant Program, North Carolina State University, Raleigh, NC, 39 pp. Murray, J.D., Gearhardt, J.L., Rulifson, R.A. and Wescott, C.W. (1995) Introduction of larger mesh webbing in the belly and wings of traditional shrimp trawls to reduce bycatch in inshore waters. Saltonstall-Kennedy Final Report, Project Number NA37FD0088-01, February 1995, University of North Carolina Sea Grant Program, Box 8605, North Carolina State University, Raleigh, NC, 75 pp. Nance, J.M. (1992) Estimation of effort in the Gulf of Mexico shrimp fishery. NOAA Technical Memorandum NMFSSEFSC-300. National Marine Fisheries Service, Southeast Fisheries Science Center, Galveston, TX, 12 pp. Nance, J.M. (1993a). Gulf of Mexico Shrimp Fishery Recruitment Overfishing Definition – Workshop 2. NOAA Technical Memorandum, NMFS-SEFSC-323, 12 pp. Nance, J.M. (1993b) Effort trends for the Gulf of Mexico shrimp fishery. NOAA Technical Memorandum NMFSSEFSC-337. National Marine Fisheries Service, Southeast Fisheries Science Center, Galveston, TX, 37 pp. Nance, J.M. (2004) Estimation of effort in the offshore shrimp trawl fishery of the Gulf of Mexico. Working paper to the Red Snapper Stock Assessment Data Workshop, April, 2004. Document No. SEDAR7-DW-24. Gulf of Mexico Fishery Management Council, The Commons at Rivergate, Tampa, FL. Nance, J.M., Garfield, N. and Paredes, J.A. (1989) A study of the social impact of the Texas shrimp closure. In: Thomas, J.S., Maril, L. and Durrenberger, E.P. (eds.), Marine Resources Utilization: Proceedings of a Conference on Social Science Issues. MASGP-89-039. Mississippi-Alabama Sea Grant Consortium, Mobile, AL, pp. 81–83.
233 Nance, J., Scott-Denton, E., Martinez, E., Watson, J., Shah, A. and Foster, D. (1997). Bycatch in the southeast shrimp trawl fishery. A data summary report, SFA Task N-10.03 June 1997. National Marine Fisheries Service, Galveston Laboratory, Galveston, TX, 207 pp. Available from: http://galveston.ssp.nmfs.gov/publications/pdf/512a.pdf. Nance, J.M., Foster, D., Martinez, E., McIlwain, T., Nichols, S., Raulerson, R., Schirripa, M., Scott-Denton, E., Shah, A. and Watson, J. (1998) Report to Congress. Southeastern United States shrimp trawl bycatch program. National Marine Fisheries Service, Southeast Fisheries Center, Southeast Regional Office 9721 Executive Center Drive, St. Petersburg, FL, 154 pp. Available from: http://galveston.ssp.nmfs.gov/publications/ pdf/conbyrep98.pdf. NMFS (National Marine Fisheries Service) (1992a) Shrimp trawl bycatch characterization. Sampling Protocol Manual for Data Collection. National Marine Fisheries Service, Southeast Fisheries Science Center, Galveston, Texas, 4700 Avenue U, Galveston, TX, 62 pp. NMFS (National Marine Fisheries Service) (1992b) Evaluation of bycatch reduction devices. Sampling Protocol Manual for Data Collection. National Marine Fisheries Service, Southeast Fisheries Science Center, Galveston, Texas, Galveston, TX, 62 pp. NMFS (National Marine Fisheries Service) (1993) Cruise results: Shrimp trawl bycatch reduction, NOAA ship Oregon II cruise 92-05 (201), 9/4-29/92. National Marine Fisheries Service, Southeast Fisheries Science Center, Pascagoula Laboratory, Pascagoula, MS. NMFS (National Marine Fisheries Service) (1995) Cooperative research program addressing finfish bycatch in the Gulf of Mexico and South Atlantic shrimp fisheries: a report to Congress. National Marine Fisheries Service, Southeast Fisheries Center, Southeast Regional Office 9721 Executive Center Drive, St. Petersburg, FL, 66 pp. NMFS (National Marine Fisheries Service) (1998) Managing the nation’s bycatch: priorities, programs and actions for the National Marine Fisheries Service. National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Washington, DC, 199 pp. Available from: http://www.nmfs.noaa.gov/bycatchplanonline.pdf. NMFS (National Marine Fisheries Service) (2003a) Commercial fisheries database (Internet database). Available from the internet URL: http://www.st.nmfs.gov/pls/webpls/FT_ HELP.SPECIES Accessed November 11, 2003. NMFS (National Marine Fisheries Service) (2003b) Closure summaries in the Alaskan groundfish fisheries, 1986–2000. (Internet database). National Marine Fisheries Service, Alaska Regional Office. Available from the internet URL: http://www.fakr.noaa.gov/sustainablefisheries/closure.html. Accessed November 11, 2003. NMFS (National Marine Fisheries Service) (2003c) Vesselspecific bycatch rates, 1994–2000. (Internet database). National Marine Fisheries Service, Alaska Regional Office. Available from the internet URL: http://www.fakr.noaa.gov/ 2000/pscinfo.html. Accessed November 11, 2003. Each year’s list can be obtained by changing the year in the URL. NRC (National Research Council) (1990) Decline of the sea turtles; causes and prevention. Committee on Sea Turtle
Conservation, Board on Environmental Sciences and Toxicology, Board on Biology, Commission on Life Sciences, National Research Council. National Academy Press, Washington, DC, 259 pp. Available from: http://books.nap.edu/books/030904247X/html/index.html. NRC (National Research Council) (1999) Share the fish: towards a national policy on individual fishing quotas. Committee to Review Individual Fishing Quotas, Ocean Studies Board, Commission on Geosciences, Environment, and Resources, National Research Council. National Academy Press, Washington, DC, 422 pp. Available from: http:// books.nap.edu/books/0309063302/html/R1.html#pagetop. New Zealand Ministry of Fisheries (2003a) Press release: Auckland Islands squid fishery resumes. April 4, 2003. Available from the internet URL: http://www.fish.govt.nz/ current/press/040403.htm New Zealand Ministry of Fisheries (2003b) Draft strategy for managing the environmental effects of fishing. March 31, 2003. New Zealand Ministry of Fisheries, Wellington, New Zealand. Available from the internet URL: http:// www.fish.govt.nz/sustainability/management_strategy/ SMEEF_3%20Apr_03.pdf. New Zealand Ministry of Fisheries (2003c) Press Release: Announcement of Auckland Islands marine reserve. Available from: http://www.fish.govt.nz/current/press/sp290103. htm. New Zealand Ministry of Fisheries (2004a) Arrow squid (SQU). In: Summary of the Assessments of the Sustainability of Current TACCs and Recent Catch Levels and Status of the Stocks for the 2004-05 Fishing Year, pp. 50–65. Available from the internet URL: http://www.fish.govt.nz/ sustainability/research/stock/status1.html. New Zealand Ministry of Fisheries (2004b) Proposed operational plan to manage the incidental capture of New Zealand sea lions in the squid (SQU) 6T trawl fishery for the 2004–05 fishing year. Initial Position Paper, Consultation Document, September 03, 2004. New Zealand Ministry of Fisheries, Wellington, New Zealand, 28 pp. Available from the internet URL: http://www.fish.govt.nz/sustainability/decisions/ sealions/2004-05-sea-lion-ipp-final.pdf. Nichols, S. (1990a) The spatial and temporal distribution of the bycatch of red snapper by the shrimp fishery in the offshore waters of the US Gulf of Mexico. Report to the Gulf of Mexico Fishery Management Council, National Marine Fisheries Service, Southeast Fisheries Science Center, Pascagoula Laboratory, Pascagoula, MS. Nichols, S. (1990b) Report of the workshop to evaluate potential management alternatives for reducing directed effort and shrimp trawl bycatch of red snapper. Report to the Gulf of Mexico Fishery Management Council, National Marine Fisheries Service, Southeast Fisheries Science Center, Pascagoula Laboratory, Pascagoula, MS. Nichols, S. (1994) Update and revision of bycatch estimate for King and Spanish mackerel 1972–1993. Report to the Gulf of Mexico Fishery Management Council, National Marine Fisheries Service, Southeast Fisheries Science Center, Pascagoula Laboratory, Pascagoula, MS. Nichols, S. (1996a) An update on some issues relating to the distribution of red snapper bycatch. Report to the Gulf of Mexico Fishery Management Council, National Marine Fish-
234 eries Service, Southeast Fisheries Science Center, Pascagoula Laboratory, Pascagoula, MS. Nichols, S. (1996b) An update of bycatch findings for mackerels and cobia in the Gulf of Mexico shrimp fishery. Unpublished Report, National Marine Fisheries Service, Southeast Fisheries Science Center, Pascagoula Laboratory, Pascagoula, MS. Nichols, S. (1999) Overall effectiveness of BRDs. Final Report on the Red Snapper/Shrimp Research Program Summer 1998 Project, National Marine Fisheries Service, Southeast Fisheries Science Center, Pascagoula Laboratory, Pascagoula, MS. Nichols, S. (2004a) Some Bayesian approaches to estimation of shrimp fleet bycatch. Working paper to the Red Snapper Stock Assessment Data Workshop, April, 2004. Document No. SEDAR7-DW-3. Gulf of Mexico Fishery Management Council, The Commons at Rivergate, Tampa, Florida. Nichols, S. (2004b) An update for the Bayesian estimation of shrimp fleet bycatch. Working paper to the Red Snapper Stock Assessment Data Workshop, April, 2004. Document No. SEDAR7-DW-54. Gulf of Mexico Fishery Management Council, The Commons at Rivergate, Tampa, Florida. Nichols, S., Shah, A., Pellegrin, G. and Mullin, K. (1987) Estimates of annual shrimp fleet bycatch for thirteen species in the offshore waters of the Gulf of Mexico. Report to the Gulf of Mexico Fishery Management Council, National Marine Fisheries Service, Southeast Fisheries Science Center, Pascagoula Laboratory, Pascagoula, MS, 27 pp. Nichols, S., Shah, A., Pellegrin, G. and Mullin, K. (1990) Updated estimates of shrimp fleet bycatch in the offshore waters of the Gulf of Mexico. Report to the Gulf of Mexico Fishery Management Council, National Marine Fisheries Service, Southeast Fisheries Science Center, Pascagoula Laboratory, Pascagoula, MS, 25 pp. Nichols, S. and Pellegrin, G. (1992) Revision and update of estimates of shrimp fleet bycatch 1972–1991. Report to the Gulf of Mexico Fishery Management Council, National Marine Fisheries Service, Southeast Fisheries Science Center, Pascagoula Laboratory, Pascagoula, MS. Nichols, S., Nance, J., Goodyear, C.P., Shah, A. and Watson, J. (1995) Some considerations in determining bycatch reduction requirements. Report to the Gulf of Mexico Fishery Management Council, National Marine Fisheries Service, Southeast Fisheries Science Center, Pascagoula Laboratory, Pascagoula, MS. Oceana (2002) Petition for rulemaking, letter addressed to Donald L. Evans, US Secretary of Commerce. February 28, 2002. Available from the internet URL: http://www. oceana.org/uploads/formal_petition.pdf Ortiz, M., Legault, C.M. and Ehrhardt, N.M. (2000) An alternative method for estimating bycatch from the US shrimp trawl fishery in the Gulf of Mexico, 1972–1995. Fish. Bull. 98, 583–599. Parsons, G. (2004) Behavior and swimming performance of red snapper: its application to shrimp trawl bycatch reduction. Working paper to the Red Snapper Stock Assessment Data Workshop, April, 2004. Document No. SEDAR7-DW-4. Gulf of Mexico Fishery Management Council, The Commons at Rivergate, Tampa, FL.
Peacey, J. (2002) Managing catch limits in multi-species, ITQ fisheries. Paper presented at International Institute of Fisheries Economics and Trade (IIFET) Conference, August 19– 22, 2002, Wellington, New Zealand. [2003 March 24]. [cited 2004 October 20]. Available from: http://www.fish.govt.nz/ current/press/pr240303_2.htm. Pearce, K.B., Moye, D.W. and Strasser, S.K. (1989) Evaluation of trawl excluder devices in the Pamlico Sound shrimp fishery Report No. 88-07 to the Environmental Protection Agency and the North Carolina Department of Natural Resources and Community Development, Albemarle-Pamlico Estuarine Study, North Carolina Division of Marine Fisheries, Morehead City, NC, 46 pp. Pellegrin, G. Jr. (1982) Fish discards from the southeastern United States shrimp fishery. In: Fish Bycatch… Bonus from the Sea: a report of a technical consultation on shrimp bycatch utilization held in George, Guyana, 27–30 October 1981. FAO and International Development Research Centre, Ottowa, Canada (IDRC 198-e), pp. 51–54. Pellegrin, G. Jr., Drummond, S.B. and Ford, R.S. Jr., (undated) The incidental catch of fish by the northern Gulf of Mexico shrimp fleet. Draft manuscript. National Marine Fisheries Service, Southeast Fisheries Science Center, Pascagoula Laboratory, Pascagoula, MS. Perkins, P. and Edwards, E. (1996) A mixture model for estimating discarded bycatch from data with many zero observations: tuna discards in the eastern tropical Pacific Ocean. Fish. Bull. 94, 330–340. Perret, W.S. and Bowman, P.E. (1993) Butterfly and skimmer nets in the Gulf of Mexico and their potential use elsewhere. In: Proceedings of the International Conference on Shrimp Bycatch, May 24–27, 1992, Lake Buena Vista, Florida. Southeastern Fisheries Association, Tallahassee, FL, pp. 325–340. Peuser, R. (ed.) (1996) Estimates of finfish bycatch in the South Atlantic shrimp fishery. Prepared by the SEAMAP South Atlantic Committee, Shrimp Bycatch Work Group, Final Report. Atlantic States Marine Fisheries Commission, April 1996, 64 pp. Powers, J.E., Goodyear, C.P. and Scott, G.P. (1987) The potential effects of shrimp fleet bycatch on fisheries production of selected fish stocks in the Gulf of Mexico. Contribution No. CRD 87/88-06. National Marine Fisheries Services, Southeast Fisheries Science Center, Miami Laboratory, Coastal Resources Division, Miami, FL. Purvis, C.E. and McCoy, E.G. (1974) Pink–brown shrimp discard studies in the Core-Pamlico Sound area.North Carolina Department of Natural Resources and Community Development, Division of Marine Fisheries. Renaud, M., Gitschlag, G., Klima, E., Shah, A., Nance, J., Caillouet, C., Zein-Eldin, Z. and Koi, D. (1990) Evaluation of the impacts of turtle excluder devices (TEDs) on shrimp catch rates in the Gulf of Mexico and South Atlantic, March 1988 through July 1989. NOAA Technical Memorandum NMFS-SEFC-254, 165 pp. Renaud, M., Gitschlag, G., Klima, E., Shah, A., Koi, D. and Nance, J. (1991) Evaluation of the impacts of turtle excluder devices (TEDs) on shrimp catch rates in the Gulf of Mexico and South Atlantic, September 1989 through August 1990. NOAA Technical Memorandum NMFS-SEFC-288, 80 pp.
235 RFSAP (Reef Fish Stock Assessment Panel) (1999) September 1999 report of the Reef Fish Stock Assessment Panel. Gulf of Mexico Fishery Management Council, The Commons at Rivergate, Tampa, FL. Available from http://www.gulfcouncil.org./downloads/RFSAP-O99-final.pdf. Renko, B.L. (1998) Management of Pacific Halibut Bycatch in the Alaskan Groundfish Fishery 1990–1996; the Vessel Incentive Program. MS Thesis. University of Washington, School of Marine Affairs, 164 pp. Roelofs, E.W. (1950a) Mesh size and construction as a factor in releasing small fish and shrimp from trawl nets. U.S. Department of the Interior, Fishery Leaflet 382, 12 pp. Roelofs, E.W. (1950b) Observations on the capture of small fish by the shrimp trawls. Reprinted from the 1950 Annual Report of the Institute of Fisheries Research of the University of North Carolina, Morehead City, NC. In: Lunz, G.R., McHugh, J.L., Roelofs, E.W., Tiller, R.E., Atkinson C.E. (eds.) 1951. The destruction of small fish by the shrimp trawlers in Pamlico Sound, North Carolina. Report to the Chesapeake and South Atlantic Sections, Atlantic States Marine Fisheries Commission, November 1, 1951, Appendix A, 4 pp. Roithmayr, C.M. (1965) Review of industrial bottomfish fishery in northern Gulf of Mexico, 1959–1962. Commer. Fish. Rev. 27(1), 1–6. Rogers, D.R., Rogers, B.D., de Silva, J.A. and Wright, V.L. (1994) Evaluation of shrimp trawls designed to reduce bycatch in inshore waters of Louisiana. Final report for MARFIN Award No. NA 17FF0375-01, January 1994. School of Forestry, Wildlife, and Fisheries, Louisiana State University Agricultural Center, Baton Rouge, LA, 230 pp. Rogers, D.R., Rogers, B.D., de Silva, J.A. and Wright, V.L. (1997a). Effectiveness of four industry-developed bycatch reduction devices in Louisiana’s inshore waters. Fish. Bull. 91(1), 129–137. Rogers, D.R., Rogers, B.D., de Silva, J.A., Wright, V.L. and Watson, J.W. (1997b) Evaluation of shrimp trawls equipped with bycatch reduction devices in inshore waters of Louisiana. Fish. Res. 33(1–3), 55–72. Rogers, D.R., Wilson, C.A. and Baltz, D.M. (1998) Behavior of red snapper, Lutjanus campechanus, with respect to trawl modifications to reduce shrimp trawl bycatch. Final Report to MARFIN, Award Number NA57FF0049, 60 pp. Ross, M. R. and Hokenson, S.R. (1997) Short-term mortality of discarded finfish bycatch in the Gulf of Maine fishery for northern shrimp Pandalus borealis. North Am. J. Fish. Manage. 17, 902–909. Royal Forest and Bird Protection Society of New Zealand (2003a) New Zealand sea lions and the squid fishery. [Organization webpage]. Available from: http://www. forest-bird.org.nz/Marine/sealions/squidfishery.asp. Royal Forest and Bird Protection Society of New Zealand (2003b) New Zealand sea lion fact sheet [Organization webpage]. Available from the internet URL: http://www. forest-bird.org.nz/Marine/sealions/factsheet.asp Rulifson, R.A., Murray, J.D. and Bahen, J.J. (1992) Finfish bycatch reduction in South Atlantic shrimp trawls using 3 designs of bycatch reduction devices. Fisheries 17(1), 1–9. Schirripa, M. and Legault, C. (1999) Status of the red snapper in US waters of the Gulf of Mexico: updated through 1998.
Sustainable Fisheries Division Contribution: SFD-99/00-75. Southeast Fisheries Science Center, Sustainable Fisheries Division, Miami, FL, 62 pp. Scott-Denton, E. (2004) Observer coverage of the US Gulf of Mexico and Southeastern Atlantic shrimp fishery, February 1992–December 2003 – Methods. Working paper to the Red Snapper Stock Assessment Data Workshop, April, 2004. Document No. SEDAR7-DW-5. Gulf of Mexico Fishery Management Council, The Commons at Rivergate, Tampa, FL. Shah, A.K. (1999) Statistical Inference on overall reduction rate of BRDs. Final Report on the Red Snapper/Shrimp Research Program Summer 1998 Project, National Marine Fisheries Service, Southeast Fisheries Science Center, Pascagoula Laboratory, Pascagoula, MS. Sheridan, P.F., Browder, J.A. and Powers, J.E. (1984) Ecological interactions between penaeid shrimp and bottomfish assemblages. In: Gulland, J.S. and Rothschild, B.J. (eds.), Penaeid shrimps – their biology and management. Selected papers presented at the Workshop on the Scientific Basis for the Management of Penaeid Shrimp, Key West, FL, November 1981. Fishing News Books, Ltd., Farnham, Surrey, UK, pp. 235–254. Siebenaler, J.B. (1952) Studies of ‘‘trash’’ caught by shrimp trawlers in Florida. Proc. Gulf Carrib. Fish. Inst. 4, 94–99. Smith, P. (undated) Managing biodiversity: invertebrate bycatch in seamount fisheries in the New Zealand Exclusive Economic Zone 1. NIWA (National Institute of Water and Atmospheric Research), Wellington, New Zealand. Available from the internet URL: http://www.worldfish.org/ Blue%20Millennium%20PDFs/Chapter%202-%20Smith%2 0Case%20Study.pdf. SAFMC (South Atlantic Fishery Management Council) (1996) Bycatch reduction device testing protocol manual. South Atlantic Fishery Management Council, 1Charleston, SC. Steele, P., Burt, T.M., Johnston, K.H. and Levett, S. (2002) Efficiency of bycatch reduction devices in small otter trawls used in the Florida shrimp fishery. Fish. Bull. 100, 338–350. Stender, B.W. and Barans, C.A. (1994) Comparison of the catch from tongue and two-seam shrimp nets off South Carolina. North Am. J. Fish. Manage. 14, 178–195. Thomas L. (2002) Giving marine mammals the slip. Seafood New Zealand 10(10), 18–22. Trumble, R.J. (1992) Looking beyond time-area management of bycatch – an example from Pacific halibut. In: Schoning, R.W., Jacobson, R.W., Alverson, D.L., Gentle, T.H. and Auyong, J. (eds.), Proceedings of the National Industry Bycatch Workshop. National Resources Consultants, Seattle, WA, pp. 142– 158. Vaughan, D. and Nance, J. (1998) Estimates of bycatch of mackerel and cobia in US South Atlantic shrimp trawls. Report for Gulf of Mexico and South Atlantic Fishery Management Councils, February 16, 1998. Gulf of Mexico Fishery Management Council, The Commons at Rivergate, Tampa, Florida, 26 pp. Vaughan, D.S., Seagraves, R.J. and West, K. (1991) An assessment of the status of the Atlantic weakfish stock, 1982–1988. Atlantic States Marine Fisheries Commission, Special Report No. 21. National Marine Fisheries Service, Beaufort Laboratory, Beaufort, NC, 29 pp.
236 Vendetti, R.A., Overman, R.G., Parker, L.G. and Harrington, D.L. (1996) Improved methods and procedures for the transfer of technology and the education of constituency groups for devices that will reduce the bycatch in shrimp trawls. Final Report to MARFIN, Award Number NA57FF0051. University of Georgia Marine Extension Service, Brunswick, GA. Wallace, R.K. and Robinson, C.L. (1994) Bycatch and bycatch reduction in recreational shrimping. Northeast Gulf Science 13(2), 139–144. Warren, J.R. (1981) Population analysis of the juvenile groundfish on the traditional shrimping grounds in Mississippi Sound before and after the opening of the shrimp season. MS Thesis. University of Southern Mississippi, 94 pp. Wassenberg, T.J., Burridge, C.Y., Connell, M. and Gribble, N. (1998) A validation of short-duration scientific tows as a representation of long commercial-length tows: comparing the catch rates, size composition and species composition of prawn trawler catch in the far northern Great Barrier Reef, Australia. Fish. Res. 36(1), 35–46. Watson, J.W. (1989) Fish behavior and trawl design: potential for selective trawl development. In: C.M. Campbell (ed.), Proceedings of the World Symposium on Fishing Gear and Fishing Vessels. Marine Institute, St. Johns, NF, Canada. pp. 25–29. Watson, J.W. (1993) Status of knowledge in the United States relating fish behavior to the reduction of bycatch. In: Proceedings of the International Conference on Shrimp Bycatch, May 24–27, 1992, Lake Buena Vista, Florida. Southeastern Fisheries Association, Tallahassee, FL, pp. 185–195. Watson, J. (1995) Summary report on the status of bycatch reduction device development. Presentation to the South Atlantic Fishery Management Council. National Marine Fisheries Service, Southeast Fisheries Science Center, Pascagoula Laboratory, Pascagoula, MS. Watson, J. (1996) Summary report on the status of bycatch reduction device development. Presentation to the South Atlantic Fishery Management Council. National Marine Fisheries Service, Southeast Fisheries Science Center, Pascagoula Laboratory, Pascagoula, MS. Watson, J.W., Mitchell, J.F. and Shah, A.K. (1986) Trawling efficiency device: a new concept for selective shrimp trawling gear. Fisheries 48(1), 1–9. Watson, J.W. Jr. and Taylor, C.W. (1990) Research on selective shrimp trawl design for penaeid shrimp in the United States: a review of selective shrimp trawl research in the United States since 1973. Proceedings of Fisheries Conservation Engineering Workshop, April 4–5, 1990, Narrangansett, RI. Watson, J., Workman, I., Foster, D., Taylor, C., Shah, A., Barbour, J. and Hataway, D. (1993) Status report on the potential of gear modifications to reduce finfish bycatch in shrimp trawls in the southeastern United States 1990–1992. NOAA Technical Memorandum NMFS-SEFSC-327. National Marine Fisheries Service, Southeast Fisheries Science Center, Pascagoula Laboratory, Pascagoula, MS, 131 pp. Watson, J., Foster, and Shah, A. (1997) Report on the results of evaluations of the Jones/Davis BRD. National Marine Fish-
eries Service, Southeast Fisheries Science Center, Pascagoula Laboratory, Pascagoula, MS. Watson, J. and Shah, A. (1997) Results of BRD and proxy analyses. National Marine Fisheries Service, Southeast Fisheries Science Center, Pascagoula Laboratory, Pascagoula, MS. Watson, J., Foster, D., Nichols, S., Shah, A., Nance, J. and Scott-Denton, E. (1999a) The development of bycatch reduction technology in the southeastern United States shrimp fishery. Mar. Technol. Soc. J. 33(2), 51–56. Watson, J., Foster, D., Shah, A. and Nance, J. (1999b) Summer 1998 red snapper/shrimp research program – BRD performance report. Final Report on the Red Snapper/Shrimp Research Program Summer 1998 Project, National Marine Fisheries Service, Southeast Fisheries Science Center, Pascagoula Laboratory, Pascagoula, MS. Watts, N.H. and Pellegrin, G.J. (1982) Comparison of shrimp and finfish catch rates and ratios for Texas and Louisiana. Mar. Fish. Rev. 44(9–10), 44–49. Wendell, F.E., Hardy, R.A. and Ames, J.A. (1986) Assessment of the incidental take of sea otters, Enhydra lutris, in gill and trammel nets. California Department of Fish and Game. Marine Resources Technical Report No. 54, 31 pp. Wenner, C.A. (1987) Results of tests on two different trawl efficiency devices (TED) in South Carolina coastal waters final report. Marine Research Institute, South Carolina Wildlife and Marine Resources Dept., Charleston, SC. Whitaker, J.D., DeLancey, L.B. and Jenkins, J.E. (1989) A study of the experimental closure of South Carolina’s sounds and bays to commercial fishing. South Carolina Wildlife and Marine Resources Dept., Division of Marine Resources, Commercial Crustacean Management Section, Tech. Rep. No. 72, 54 pp. Witherell, D. and Pautzke, C. (1997) A brief history of bycatch management measures foe eastern Bering Sea groundfish fisheries. Mar. Fish. Rev. 59(4), 15–22. Wolff, M. (1972) A study of North Carolina’s scrap fishery. North Carolina Department of Conservation and Development, Division of Commercial and Sports Fisheries, Raleigh, NC, Special Scientific Report No. 20, 29 pp. Woodward, R., Griffin, W. and Wui, Y. (2003) An integrated economic analysis of alternative bycatch, commercial, and recreational policies for the recovery of Gulf of Mexico red snapper. MARFIN report NM87FF0420, Texas A & M University, College Station, TX 116 pp. Workman, I.K. (1999) Fate of juvenile red snapper, Lutjanus campechanus, that escape from shrimp trawls. Final Report on the Red Snapper/Shrimp Research Program Summer 1998 Project. National Marine Fisheries Service, Southeast Fisheries Science Center, Pascagoula Laboratory, Pascagoula, MS. Workman, I.K. and Watson, J.W. (1995) Using trawlable webbing reefs as a step in the certification of shrimp trawl bycatch reduction devices. In: Proceedings of the International Conference on Ecological System Enchancement Technology for Aquatic Environments, Oct. 29–Nov. 2, 1995, Tokyo, Japan. Workman, I.K., Watson, J.W. Jr. and Taylor, C.W. (1992) Trawl gear modifications to reduce bycatch in the southeast-
237 ern United States shrimp fishery. Draft manuscript. National Marine Fisheries Service, Southeast Fisheries Science Center, Pascagoula Laboratory, Pascagoula, MS. Workman, I., Watson, J. Foster, D., Taylor, C., Shah, A. and Barbour, J. (1994) Status report on the potential of gear modifications to reduce finfish bycatch in shrimp trawls in the
southeastern United States. 1993 Annual Report. National Marine Fisheries Service, Southeast Fisheries Science Center, Pascagoula Laboratory, Pascagoula, MS. Ye, Y.M. (2002) Bias in estimating bycatch-to-shrimp-ratios. Aquat. Living Resour. 15(3), 149–154.
