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Mercer University. Harold. F. Hirth. Macon ..... Jack Frazier's Marine Turtles in the Comoro Archipelago (1985: 196 pages, paperback; ISBN. 0-444-85629-3) has ...
Marine Turtle Newsletter Number 36

March 1986

Editor: Nat B. Frazer

Editorial Advisors:

Department of Biology College of liberal Arts Mercer University F. Hirth Macon, OA 31207 U5A

Peter C. H. Pritchard Anders 0. J. Rhodin Harold N. Morosovsky

ACTION ALERT: ROCKETS TO DISLODGE RIDLEYS AT GAHIRMATHA Efforts are underway to shift the proposed national rocket testing range from Ballapal In the Balasore district of Orissa, to Satbhayas in the Cuttack district, because of protests by the inhabitants of Baliapol. This move, if implemented, will seriously affect the unique ecosystem of the 170 sq. km Bhitar Kanika Wildlife Sanctuary, and more particularly, the Gahirmatha beach, where an estimated 800,000 olive rldleys nested in the 1984 season (Bhaskar, 1964). Besides turtles. the area also harbours the country’s most important population of the saltwater crocodile and a rich avifauna. It Is Interesting to note that the See Turtle Specialist Group, formed by the Government of India’s Department of Environment, has recommended the creation of a marine national park at Gahirmatha, and a ban on fishing from Palmyras Point to False Point. About 300 dead ridleys washed ashore at the Gahirmatha beach In 1983 after having earlier drowned In trawl nets or died In poachers’ vessels. Only a tenth as many ware found in the succeeding year, thanks to the patrolling by the coast guard. Bhaskar, S. 1984. Sea turtles in eastern India. WWF Monthly Report, August 1984:185-159. INDRANEIL DAS, 18/20, Ballygunge Place (East). Calcutta - 700 019 INDIA. [Those readers desiring more information or wishing to write letters protesting the proposed rocket testing range being built new the Gahirmatha nesting beach should correspond with Indraneil Das at the address given above. NBF]

SEA TURTLE WORK IN CHINA Marine turtle conservation is being carried out in China, where marine turtles have been classified as protected animals. The First Session or the Marine Turtle Conservation Meeting was held at Huidong County, Guangdong Province in September 1985, attended by representatives of the China

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Ministry of Farming. Animal Husbandry and Fisheries, the China Ministry of Construction and Environmental Protection for City and County, the China Scientific and Technical Committee, the Institute of Zoology Academia Sinica of China, the China Wild Animal Conservation Association and the concerned departments of Guangdong Province. During the meeting, the Guangdong television station made a TV film about the turtles egg-laying, hatching and breeding in the Port of Huidong County. The major wee in China for marine turtle nesting is the Hsisha Islands, but the turtles also nest every year In the Port or Huldong County. In order to protect the marine turtle resource, a marine turtle hatching area has been set up at Huidong County and two marine turtle conservation areas are being planned to be built in the suburbs of Sanya City and along the coast of Ling Shui County of Hainan Island. After artificial breeding there. the turtles will he tagged and returned to the sea. A South China marine turtle observation team will be organized by the Ministry of Farming. Animal Husbandry and Fishery. The team will complete its observation mission from 1986 to 1987. Dr. Huang Chu-chien has been contacted to act as an advisor to the team and will participate In the marine turtle observation with the team. The Bejing Science and Education Film Studio will shoot a film about the South China Sea marine turtles. Dr. Huang Chu-chien will also act as technical advisor for the film, which will be made during 1987. HUANG CHU CHIEN, Institute of Zoology. Academia Sinica, 7 Zhongguancun Lu, Haidan. Beijing. CHINA

MARINE TURTLE CONSERVATION : THE TRIBAL CONNECTION Conservation efforts are unlikely to become successful in the long run if public opinion is not actively sought and obtained. Realizing this, the marine turtle conservation program or the World Wildlife Fund -- India (Eastern Region) has started its campaign to reach out to the masses. An Illustrated pamphlet published by the WWF-I In Bengali Is being distributed among the prospective consumers of turtles in the many markets of West Bengal, requesting them to abstain from buying turtle meat or eggs. Another publication Is the book. Indian Turtles: A Field Guide, which describes all the 36 species and subspecies of turtles so for recorded from India. Besides creating an interest and awareness In this group or reptiles ad providing Information on their biology and status. the field guide can be used in the enforcement of the Indian Wildlife (Protection) Act of 1972. Another effective strategy is the recruitment of the rural scroll-painter, Ranjit Chitrakar, who paints and sings of marine turtles and the need for their conservation. Hailing room a remote little village In Midnapore, Ranjit is a third generation scroll-painter and has been involved in the environmental education activities or the WWF-I since 1982, when Ms. Bonani Kakkar, Project/Education Officer of the WWF-I (Eastern Region) ‘discovered" him at a fair and immediately realized his potential. A “patua” as a scroll-painter is called. is very much a part of rural Bengal. He paints his own scrolls, each as long as 7 meters, using colors from natural sources, and wanders from village to village singing tales from epics and legends to the vast, enthusiastic audience. Work on a scroll commences only after Ranjit has had a personal insight and grasped the conservation problems involved. This means that he may haw to be taken to the “field" -- In the turtle program, to the turtle markets. While the scene is fresh in his mind, the scroll-painter starts his painting and song composing simultaneously. Ranjit, like all members or his trade and tribe, uses only natural colors to illustrate his songs. like clay (brown), soot (black), vermillion (red), Indigo (blue) and tumeric (yellow). Green is less readily procured: It has to be made from the juice of a plant leaf. Color Is applied to the paper using a brush mob from the tail hairs of a goat.

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Ranjit the scroll-painter has been involved with WWF-I’s environmental education program for over 3 years and is doing very effective work. The success of the conventional methods of education such as slides, films and posters may be limited especially when rural audiences are concerned, being Interpreted as a city-dweller's attempt to talk about rural problems. On the other hand, the utilization of local skills and crafts in environmental education efforts holds promise, especially in developing countries. However, It has been little experimented with until now. INDRANEIL DAS, 18/20, Ballygunge Place (East), Calcutta - 700 019, INDIA

LOGGERHEAD TURTLES AT LAMPEDUSA ITALY The Island or Lampedusa Is the largest or the three Pelagic Islands, situated east of Tunisia. It is another example of economic exploitation connected with the disappearance of marine turtles. Although protected by law In Italy, the turtles are hunted Illegally by Sicilian and Lampedusan fishermen. Larger quantities by far are caught by Tunisian and Maltese fishermen in whose countries no protection exists for the turtles. Further reasons for the decline at Lampedusa are beach destruction and advanced tourism. Until circa 1940/1950. sea turtles laid their eggs on several beaches all around the island. They were often seen at Conigli Beach, Cala Croce, Cala Guitgia, Cala Francese and possibly at Cala Pisana. Nowadays a very small number of Caretta caretta is still laying eggs at Conigli Beach, which is the one most visited by tourists at Lampedusa. In August 1985, 250-300 people were counted by day and 30-50 by night. The formerly large number of see turtles is still remembered by the islanders -- eggs and hatchlings used to serve the children as playthings decades ago. Since about 1950, it has seemed to the inhabitants that the turtle numbers have decreased steadily. It is a widespread belief that during the last 5-10 years, the turtles have disappeared completely. The first female of 1985 at Conigli Beach came on 27 June and after a track of 8m she laid 101 eggs, of which 78 hatched after incubating for 66-74 days. She was tagged with tag # ME 5102, showing a return address of the Musée Océanographique de Monaco. This turtle came up again after 23 nights. She made two attempts to dig a nest but gave up both because of stones. This happened also to another turtle on 2 September. The number of females still visiting Conigli Beach could be as many as 1 to 2 per year, or from 5 to 7 in a three yew cycle. A table of reproductive activity for Conigli Beach is shown for the past 10 years (incomplete). Table 1. lncomplete nesting statistics for Caretta caretta at Conigli Beach, 1975-1985.

Year

# Nesting females

# Nests

Hatchlings

1975

1 (June/July?)

1

70 (Sept.)

1977

2 (June)

2

?

1978

2 (June); 1(July?)

1

Not counted (Sept.)

1983

1 (June/July?)

1

5 (Sept.)

1985

1 (June); 1 (July);

1

78 (Sept.)

DIETER GRAMENTZ, Földerichstrasse 7, D-1000 Berlin 20, FEDERAL REPUBL IC OF GERMANY

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ATLANTIC RIDLEY PROJECT : 1985 PRELIMINARY REPORT The turtle camp was first established at Rancho Nuevo, Tamaulipas in 1966 for the purpose of enhancing and restoring the population of Kemp's ridley. The inter-agency program between the Instituto Nacional de la Pesca and Secretaria de Pesca in México and the U.S. Fish and Wildlife Service in the United States was begun In 1978. In 1985, the work at Rancho Nuevo began with the simultaneous arrival of the Mexican and US teams on 12 April. Cooperative work in the camp continued until the last week of September, and the US team remained until 10 August. The first ridley was seen laying on 16 April and the last on 6 August. From a total of 832 arrivals, 703 nests (685 ridley, 16 green and 2 loggerhead) were located and protected (4 in situ ); 39 were declared unknown. A total or 71,687 eggs were protected in the nest facilities; 53,433 In corral # 1; 12,989 in corral #2; 2,946 in Rancho Nuevo boxes; 2,031 in Padre Island boxes. Another 410 nests were left in situ and predation was estimated at around 4.000 eggs by humans and feral animals (5.3%). The hatching success by facility was as follows: Corral #1 = 80.2%; corral #2 = 79.9%; Rancho Nuevo boxes = 23.9%; Padre Island Boxes = 80% and protected in situ nests = 50%. The overall hatching rate in 1985 was 77.9% with a total of 54,170 hatchlings released on the Rancho Nuevo nesting beach. These results are somewhat higher than In former years (49% in 1983; 73.4% in 1984; 61.2% for the previous seven years combined (1978-1984)]. During the 1985 nesting season, two Kemp's ridley nests were protected in Tecolutia, Veracruz, with 180 eggs. Small number or nests were reported from Padre Island, and one or these was protected successfully. The Kemp’s ridleys held at the Cayman Turtle Farm did not lay eggs this season. During 1985, there were 73 grouped or solitary emergences, including two arribazones with more then 100 turtle tracks. Each or these arribazones resulted In more than 100 nests which were located and reburied in the corrals the same day. Of 43 nests left in situ, only four were protected, producing 205 hatchlings; the fates of the others are unknown. but they were probably depredated. We applied 183 tags (159 turtles received titanium tags, 23 received monel and 1 received a plastic tag). Only one turtle received both titanium and plastic tags, in each front flipper. Nineteen turtles had worn tags and were retagged; fifty turtles had possible tag scars from previous tagging and were retagged. Seventy-six turtles nested twice, 15 three times, 2 four times and one turtle came onto the beach 7 times. Ninety-two turtles returned from previous years to nest again this year; of these, 18 nested twice and 2 nested three times this season. For other species, this was an exceptional year. The 16 green turtles laid 1926 eggs, resulting in 803 hatchlings; the two loggerheads laid 217 eggs, but produced only 19 hatchlings. Nineteen boxes with 200 eggs ware shipped to Padre Island, Texas (USA) for incubation and imprinting (one box remained in México with 81 rotten eggs). The total average survival rate of these eggs was nearly 18%. One thousand six hundred twenty-three Imprinted hatchlings wore received in the Galveston Laboratory (Texas) for the Headstart Program; they will be released next year. The incubation temperature was monitored for Rancho Nuevo and Padre Island clutches and dead hatchlings were preserved for sex determination. Preliminary estimates Indicate that more than 60% incubated on the beach are females. Unfortunately, there has not been any observable increase in the Kemp’s ridley population after 19 years of Méxican efforts and 8 years of joint work. Several problems continue to have an impact on the ridleys (e.g., oil. shrimp trawling (see Woody, 1985, MTN 35:4-5).

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RENE MARQUEZ M., CRIP Manzanillo, Apartado Postal 591, Manzanillo, Colima, México 28200 MEXIC0; MANUEL SANCHEZ P. and JUAN DIAZ F., INP., Londres 259. México 06720 MEXIC0; DANIEL RIOS 0., CRIP Mazatlán, Sábalo-Cerritos s/n, Mazatlán, Sinaloa. MEXIC0.

SCUTES RESERVED FOR LIVING TAGS Living-tags on carapace scutes are being used to distinguish year-classes of head-started Kemp’s ridley sea turtles, Lepidochelys kempi (Fontaine and Caillouet 1985). In this report, we provide Information on which scutes have been used to place living-tags in past years and also outline our plans for placing living-tags on particular scutes of future year-classes or Kemp's ridleys. Available records Indicate that turtles released from year-classes 1978 and 1979 were not living-tagged. For year-classes 1980-1995, the scutes used or proposed for Kemp's ridleys living-tags are shown In Table 1. Table 1. Scutes used or proposed for head started and living-tagged Kemp's ridleys.

1980

1981 1982 1983 1984 1905 1986 1987 1988 1909 1990 1991 1992 1993 1994 1995

LC2. LC3, RC2, RC3. RC4, M2, M3, LH, LP, LA (some individuals were tagged between scutes RC2 & RC3, RC3 & RC4, LP & RP or LH & RH None living tagged LC3 1C4 LCS RC5 N4 NI RCII LCI RC4 M2 N3 RC2 1C2 RC3

(RC = right costal; LC = left costal; N = neural. LH = left humeral; LP = left pectoral; LA = left abdominal; RP = right pectoral; RH = right humeral)

The scutes proposed for year-classes 1985-1995 were selected to minimize the probability of overlap between year-classes in use of the same scute. For example, under this scheme the reuse of a given scute would not occur until 1990 when right costal scute 4 (RC 4) would be used on the 1990 year-class (Table 1). Only one turtle of the 1980 year-class was living-tagged on RC 4. For the 1991

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year-class, neural scute 2 (N 2) is proposed, as only 4 turtles on the 1980 year-class were tagged on that scute. [Neural scute 5 Is avoided because It occasionally Is spilt into a sixth neural. Reuse of humeral, pectoral and abdominal scutes also is not proposed.] Coordination among sea turtle Investigators proposing use of living-tags will remain with the U.S. Fish and Wildlife Service (Bowman. 1983). We request that anyone encountering what they believe to be living-tagged Kemp's ridleys contact us at the given address below or by telephoning any of the following numbers: (409) 766-3500; (409) 766-3517; (409) 766-3523; (409) 766-3507; (409) 766-3525. We would appreciate your noting the particular scutes on which living-tags we located, as well as details concerning the size, location, date and method of recapture, sighting or stranding of the turtle. Bowman. D. 1983. Tag locations reserved. MTN 25:12-13. Fontaine, C. T. and C. W. Cailouet. Jr. 1985. The Kemp’s ridley sea turtle head start project: an annual report for fiscal year 1984. NOAA Tech. Mem. NMFS-SEFC-152. CHARLES W. CAILLOUET, Jr., CHARLES T. FONTAINE, SHARON A. MANZELLA, THEODOR D. WILLIAMS and D. B. RIVERA, National Marine Fisheries Service, Southeast Fisheries Center, Galveston

Laboratory, 4700 Avenue U, Galveston, TX 77660 USA.

ON THE DOLLAR VALUE OF THE OAXACAN RIDLEY FISHERY It is always of interest to have some idea of the current market value of the wildlife resources we deal with. Mexico's legalized harvest program for adult olive ridleys (Lepidochelys olivacea) continues and is centered along the Pacific coast of the State of Oaxaca in southern Mexico. The operation has been in effect for over 10 years; despite dire warnings or population collapse it has not yet happened. The season just ended recorded five major emergences (arribadas) in which thousands of ridleys nested at Plays Escobilia. The first arribada was in late July and the last in early November. The official government quota for the 1985 harvest was about 28,000 ridleys and apparently this quota was reached. On 20 November, while at Escobilla. I talked with the Fisheries Inspector, State of Oaxaca, regarding economic aspects of the harvest program. The following Information came from this source. Fishermen landing live ridleys at Puerto Angel received 4,000 pesos/turtle or approximately US $8.42 (475 pesos - 1 US dollar). For 28,000 turtles, this means that the entire harvest was worth approximately US $236,000 to the fishermen. The processing plant renders each animal into meat, leather, and bone meal. The value of all these products is about 12,000 pesos (US $25.26) per turtle to the wholesaler, representing a total of about US $707.000 for the 1985 legal quota. This is a combined value of US $943,000 up through the fisherman and the processor. The only retail values I can presently provide are for cowboy boots in Mexico City and Matamoras where they we offered for sale for about US $140. Women's turtle leather shoes retail in Mexico City for about US $40. Taking or selling of turtle eggs is illegal throughout Mexico; however, poaching is a major problem and the eggs are sold on the black market. In Oaxaca, poachers sell eggs at 30 pesos each (US 6c) to their buyers. The buyers, in turn, sell the eggs at about 60 pesos each (US 13c). Assuming an average clutch size of 105 eggs, this amounts to a value of about 6,300 pesos per clutch (US $13.26). Overall. the ridley trade in Oaxaca grosses a minimum of one million dollars (US) annually. Retail value date is presently not at hand nor is the very important information on direct and indirect

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employment related to the resource. It would he of significant interest to see the results of an in-depth socio-economic analysts or this program. Hopefully. an enterprising student In one or Mexico’s universities will undertake such a study in the near Future. JACK B. WOODY. U.S. Fish and Wildlife Service, Box 1306. Albuquerque, NM 87103 USA.

RECENT PAPERS DAVENPORT, J. ad W. CLO~. 1986. Swimming and diving in young loggerhead sea turtles (Caretta caretta L.) Copeia 1986:53-57. J. Davenport. Animal Biology Group. Mar. Sci. Lab., Menai Bridge. Gwynedd. N. Wales. UNITED KINGDOM. FERRIS, J. S. 1986. Nest Success and the Survival and Movement of Hatchlings of the Loggerhead Sea Turtle (Caretta caretta) on Cape Lookout National Seashore. CPSU Technical Report 19. 4Opp. Available from: US National Park Service Cooperative Research Unit, Institute of Ecology, University of Georgia, Athens, GA 30602 USA. FRANK. W., W. SACHSSE and K. H. WINKELSTRÄTER. 1976. Aussergewöhnliche Todesfälle durch Amöbiasis bei einer Brückenechse (Sphenodon punctatus), bei jungen Suppenschildkröten (Chelonia mydas) und bei einer Unechten Karettsachildkröte (Caretta caretta).11. Amöbiasis bei chelonia mydas und Caretta caretta. Salamandra 12(3):120-126. W. Frank. Universitat Hohenheim, Abtielung Parasitologie. Fruwirthstrasse 45. 7000 Stuttgart. GERMANY. FRAZER, N. B. 1986. Survival from egg to adulthood In a declining population of loggerhead turtles. Caretta caretta . Herpetologica 42(l):xx-xx. N. Frazer. Department of Biology, Mercer University, Macon, GA 31207 USA. FRAZER, N. B. and J. I. RICHARDSON. 1965. Seasonal variation In clutch size for loggerhead sea turtles. Caretta caretta, nesting on Little Cumberland Island, Georgia. USA. Copeia 1985(4):1083-1085. N. Frazer, address above. FRAZER, N. B. and J. I. RICHARDSON. 1986. The relationship of clutch size and frequency to body size in loggerhead set turtles. Caretta caretta. J. Herpetol. 20:61-84. N. Frazer. address above. FRAZIER, J. G. 1983. Analysis estadistico de Ia tortuga goifina, Lepidochelys olivacea. (Eschscholtz) de Oaxaca, Mexico. Clencia Pesquera Inst. Nal. Pesca, Sria Pesca Mexico 4:49-75. J. Frazier. Division or Reptiles NHB-203-W, National Museum of Natural History, Washington, DC 20568. FRAZIER, J. G. 1954. Las tortuges marines en el Oceano Atlantico sur occidental. Asociation Herpetologica Argentine, Serie Divulgacion 2:3-2 1. J. Frazier. address above. FRAZIER, J. G. 1984. Contemporary problems in sea turtle biology and conservation. Proceeding, Workshop or Sea Turtle Conservation, CMFRI Special Publication 18:77-91. J. Frazier, address above. FRAZIER, J. G. and S. SALAS. 1982. Tortugas marinas en Chile. Bol. Mus. Nac. Hist. Nat. Chile 39:63-73. J. Frazier, address above. HUDSON. D. M. and P. J. LUTZ. 1986. Salt gland function in the leatherback see turtle, Dermochelys coriacea. Copeia 1986:247-249. D. Hudson, Rosenstiel School or Marine and Atmospheric Science, Division of Biology and Living Resources, University of Miami, 4600 Rickenbacker Cswy., Miami. FL 33149 USA. LEH, C. M. U.. S. K. POON and Y. C. SIEW. 1985. Temperature-related phenomena effecting the sex of green turtle (Chelonia mydas) hatchlings In the Sarawak Turtle Islands. Sarawak Museum Journal 34(55):183-193. C. Leh. Muzium Sarawak, Jalan Tun Abang Haji Openg, Kuching, Sarawak, MALAYSIA. LIMPUS, C. J. and P. C. REED. 1985. Green sea turtles stranded by Cyclone Kathy on the south-western coast or the Gulf or Carpentaria. Aust. Wildl. Res. 12:523-533. C. Limpus, Queensland National parks and Wildlife Service, PO Box 5391, Townsville M.S.O., Queensland 4810 AUSTRALIA. LIMPUS, C. J.. and P. C. REED. 1985. The green turtle, Chelonia mydas in Queensland: preliminary description of the population structure In a coral reef feeding ground. p. 47-52 In G. Grigg, R. Shine and H. Ehmann (eds.) The Biology of Australian Frogs and Reptiles Surrey Beatty & Sons, Chipping Norton, Australia. C. Limpus, address above.

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LIMPUS, C. J., and P. C. REED. 1985. The loggerhead turtle, Caretta caretta, in Queensland: observations on Internesting behavior. Aust. Wildl. Res. 12:535-W. C. Limpus. address above. LIMPUS, C. J.. P. C. REED and J. D. MILLER. 1985. Temperature dependent sex determination in Queensland sea turtles: Intraspecific variation In Caretta caretta. p. 343-351 In G. Grigg. R. Shine and H. Ehmann (eds.) The biology of Australian Frogs and Reptiles Surrey Beatty & Sons, Chipping Norton, Australia. C. Limpus, address above. MEYLAN, A. B. 1985. The role or sponge collagens in the diet of the hawkshill turtle (Eretmochelys imbricata). p. 191-196 In A Bairati and R. Garrone (eds.) Biology of Invertebrate & Lower Vertebrate Collagens. Plenum Publ. Corp. A. Meylan, Herpetology, American Museum of Natural History, Central Park West at 79th St., New York, NY10024 USA. ROSS, J. P. 1985. Biology of the grew turtle, Chelonia mydas, on an Arabian feeding ground. J. Herpetol. 19 (4):459-468. P. Ross. MCZ, Harvard University, Cambridge, MA 02138 USA. SOMA, MASAKI. 1985. Radio biotelemetry system applied to migratory study of turtle. J. Fac. Mar. Sci. Technol., Tokal Univ. 21:47-56. Author’s address not available. TAKAYOSHI, T.. Y. TODA and F. A. KUMMEROW. 1984. Spontaneous aortic lesions in marine turtles. Toboku J. Exp. Mad. 144:139-142. T. Toda, Burnsides Research Laboratory, University of Illinios, Urbane, IL 61801 USA.

SEA TURTLE MONOGRAPH Jack Frazier's Marine Turtles in the Comoro Archipelago (1985: 196 pages, paperback; ISBN 0-444-85629-3) has recently been published by the Royal Netherlands Academy of Arts and Sciences and is now available for purchase (US $35.25; Dfl. 95.00). Contents: General Introduction; Description of the Archipelago; Feeding Habitats; Nesting Habitats; Species Accounts; Non-human Predation; Human Predation; Epizoa; Habitat Degradation and Destruction; Commercial Exploitation, Past and Present; Legislative Measures, Past and Present; Reserves; Recommendations; General Summary. Copies may be ordered from the Editorial Department of the Royal Netherlands Academy of Arts and Sciences, C/o Mr. A. M. Verheggen, PO Box 19121, 1000 GC Amsterdam, THE NETHERLANDS, or from the author. Dr. Jack Frazier, Department or Zoological Research, National Zoological Park, Srnithsonian Institution, Washington. DC 20008, USA.

COSTA RICAN MONOGRAPH The Costa Rican National Parks Foundation in collaboration with the Costa Rican National parks Service, the State Open University and the Tinker Foundation has recently published a popular study entitled “The Sea Turtles of Santa Rosa National Park” (64 pp.; 24 color photographs; 12 line drawings; glossary; geological time chart; bibliography) by Stephen Cornelius. Brief summaries of turtle evolution, taxonomy, identification. and general sea turtle biology (including courtship and mating, growth and age, nesting behavior, Incubation and hatching, and migration) precede expanded accounts of four species known to utilize the near shore waters and beaches of Santa Rose National Park. Considerable emphasis is given to the olive ridley (Lepidochelys olivacea) mass nesting phenomenon at Playa Nancite and the resulting consequences and conservation implications of this unusual reproductive strategy. Information Is also presented on the worldwide and local abundance and distribution, external features, feeding and nesting characteristics, and worldwide population status for leatherbacks (Dermochelys coriacea), green turtles, (Chelonia mydas), and hawksbills (Eretmochelys imbricata). The final chapter deals with various threats to the sea turtles' survival, specifically addressing the relative Importance of such factors as subsistence use, local commerce, International trade, incidental catch in other fisheries, destruction of nesting beaches and marine and land-based pollution. Copies may be ordered for US$ 10 (check or international money order) to: President, Fundación de Parques Nationales, Apartado 236, 1002 San José, Costs Rica. The price includes air mail to any country and personal checks drawn against US banks are acceptable.

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MARINE TURTLES OF BARBADOS The Barbados Primate Research Center and Wildlife Reserve has just published a small booklet on “The Marine Turtles of Barbados” by Julia Horrocks and Jean Baulu. The booklet contains several color photographs or sea turtles and information on their life histories, behavior, exploitation and conservation. Although the booklets are usually sold at the Barbados Wildlife Reserve, interested readers may obtain a copy by mail for US $4.00 (airmail postage Included). Orders should be sent to Jean Baulu, Head and Programme Leader, Barbados Primate Research Center and Wildlife Reserve, “Hillcrest”, Bathsheba, St. Joseph, Barbados. West Indies.

MARINE TURTLES OF MICHOACAN, MEXICO The Universidad Michoacana de San Nicolas de Hidalgo has just published a study by Javier Alvarado, Alfredo Figueroa and Humberto Gallardo entitled Ecologia y Conservacion de las Tortugas Marinas de Michoacan, Mexico (1985; 44pp). The publication Is the result of work carried out between August 1984 and March 1985 under a contract between the School of Biology (UMSNH) and the World Wildlife Fund-US. It contains information on hatcheries, natural nests, tagging (tag recovery, migration, filopatry and tag loss), reproductive ecology (fecundity, nesting intervals, etc.), the state of the population and environmental education. Readers Interested in obtaining copies should write to Javier Alvarado D., Universidad Michoacana, Aptdo. 35-A, Morelia, Michoacan, MEXICO.

INFORMATION SOUGHT ON TAGGED PACIFIC DERMOCHELYS A leatherback turtle has been captured in the western Pacific bearing a white plastic Jumbo Rototag with black letters “B 4112." No address or other Information was on the tag. Anyone with information on this tag please contact: J. Frazier, Division of Reptiles, Smithsonian Institution, Washington, DC 20560 USA.

LEATHERBACK PROJECT GETS NEW DIRECTORS Robert L. Brandner and Susan J. Basford will be taking over the duties as Directors or Field Operations and Principal Investigators of the Leatherback Turtle Recovery and Conservation Project, Sandy Point, St. Croix, U.S. Virgin Islands. Interested readers may contact them at the following addresses. PO Box 1697. Frederiksted, St. Croix. USVI 00840 (April-August) or 15 East 43rd Street, Bayonne, NJ 07002 USA (September-March).

KEMP’S RIDLEY RESEARCH OPPORTUNITY Each year the Galveston Laboratory of the National Marine Fisheries Service (USA),'Southeast Fisheries Center head-starts more than 1,000 Kemp's ridleys as part of the Mexico-USA program aimed at recovery of the species. The turtles we reared from hatchlings to 10-11 months of age, tagged and released into the Gulf of Mexico. Holding the turtles in captivity offers unique and valuable opportunities for collaborative research on pathology, physiology, nutrition, etc. (with the proviso that the turtles are not harmed In any way). Available laboratory space and equipment, office space, and limited supplies can be provided in support of visiting scientists Interested In research on Kemp’s ridleys. Interested readers should contact: Charles W. Caillouet, Jr., Chief, Life Studies Division, NMFS SEFC Galveston Laboratory, 4700 Avenue U, Galveston, TX 77550 USA (telephone (409) 766-3525).

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VOLUNTEER FIELD ASSISTANTS SOUGHT FOR TORTUGUER0 The New York Zoological Society and the Caribbean Conservation Corporation are now accepting applications for forty volunteer field assistants to join researchers at the CCC's Tortuguero Station to assist In the annual tagging or green sea turtles. Archie Carr has directed this research at Tortuguero for over 30 years; 1986 will mark the third annual expedition by NYZS/CCC volunteers. Five teams, departing July through September, are now being formed. Interested readers should contact: John Behler, Curator of Herpetology, Bronx Zoo, Bronx, NY 10460 USA (Tel. (212) 220-5 152).

GUEST EDITORIAL : MEASURING SEA TURTLES Measurements of sea turtles have received considerable attention, especially concerning whether carapace lengths are measured over the curve or straight line. Mean sizes of nesting females are frequently reported, and size at sexual maturity is almost always discussed in studies of nesting populations. Rarely is mention made of the accuracy or measurements or the error associated with size determination. Mrosovsky (1983) illuminated the problem, noting that some animals apparently have smaller measurements at recapture than at first encounter. Herein we address the question of accuracy of carapace measurement and suggest that certain information be included when reporting measurements. This work was precipitated by our observation of unexpected variability In repeated carapace measurements of living and dead loggerhead turtles by ourselves and by groups of turtle taggers. The results should have bearing on studies that rely on field data in which there Is no report of variance in measurements. We present here only our own measurements and those made by participants in the 1985 Sea Turtle Research Workshop at Waverly, Georgia USA. To determine the variances of our measurements, we each measured the carapaces or one adult Caretta caretta and one juvenile Lepidochelys kempi ten times on three different days. The carapace length over the curve (CCL) was measured mid-dorsally In millimeters from the anterior margin of the nuchal lamina to the tip of the most posterior marginal. A fiberglass measuring tape was pinched at one end and the measurement read by the other person to avoid bias. The tape was reversed between readings to assure independence of measurements. We compared day-to-day and total variances within and between individual measurers with a Student's t test. In addition to measuring the turtles ourselves, we also asked participants at the 1985 Sea Turtle Research Workshop to “measure" the adult loggerhead carapace that we used. No directions for method of measurement were provided. Consequently, we did not compare our repeated measurements with the single measurements of the Workshop participants by statistical testing, although an indication of variability in measurements was derived. Some participants indicated the method they used to measure the carapace. Based on those measurements and on two clearly defined size groups of the other measurements, we divided responses Into two groups : those measuring standard curved carapace lengths (CCL) recorded measurements >99cm; minimum curved carapace length (mCCL) was apparently measured from the nuchal notch to the posterior marginal notch and was < 94 cm. Our measurements varied (Ruckdeschel's less than Shoop’s), but Individual day-to-day variance did not change; consequently, data were pooled for the three days. Results of our analyses are presented In Table 1. Means were not statistically different, although the variance was twice as great on a large turtle for Shoop. For the small turtle, results were not statistically different (P> 0.05). Ranges were 1.0 cm (Ruckdeschel) and 1.8 cm (Shoop) on the large turtle. but only 0.5 cm (both Ruckdeschel and Shoo) on the smaller animal, with 0.4 cm overlap.

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Of 37 measurements by Workshop participants judged as measured from nuchal to posterior marginal tip (CCL), the range was 6.5 cm (Table 1). For those measurements judged as mCCL (n =16) the range was 2.1 cm. Thew data indicate the magnitude of potential error possible in field data and point out the possible range of values for a single carapace measurement. The range would have been even greater if we had not separated the two measurement groups. Although calculations of variance may give some indication of mensuration precision, it may be only roughly related to accuracy because means are not necessarily related to the correct (real) value. Probably, the mean will be near the real value, especially with a large number of replicate measurements, but there is no assurance that this will be so. We believe that the range is a better indicator of potential measurement error. If only a single measurement is taken in the field, the sign (+ or -) or the possible error Is unknown. Therefore, the probable error bracket, using range as an estimator, is + or - the range (as determined by independent, replicated measurements on a single turtle). Large numbers of repeated measurements rarely can be made In the field and circumstances may differ when individual measurements are taken; consequently, ranges determined under ideal circumstances are likely to be less than those determined in the field.

TABLE 1 Results of repeated measurements of two sea turtle carapaces by the authors and by participants at the Sea Turtle Research Workshop (STRW). All measurements are in centimeters and CCL, except as noted.

N

Range

Mean

Variance

Observer

30

99.9-100.9

100.5

0.056

Ruckdeschel

30

99.2-101.0

100.01

0.197

Shoop

37

99.0-101.5

101.9

2.390

STRW

16*

91.4-93.5

92.56

0.446

STRW

Student’s t value

Caretta 0.044

Lepidochelys 30

62.7-63.2

62.96

0.010

Ruckdeschel

30

62."33

63.02

0.018

Shoop

1.964

*mCCL

The Sea Turtle Manual of Research and Conservation Techniques presents four sets of points for measuring carapace length, with method "A" recommended. Method “B” is most often used for other families of turtles, however. No rationale nor authority is given for the recommended method for sea turtles, and In no case is the actual anterior or posterior border point defined for measurements over the curve of the carapace (e.g. skin-lamina border, or arbitrary points on the curved laminae). Undoubtedly, the lack of clearly-defined starting and ending points contributed to the variance in our repeated measurements. The reduced variance noted In mCCL (method “D”) measurement by Workshop participants suggests that mCCL may be more useful In the field. Our reduced variance with CCL on the smaller ridley carapace may be related to carapace shape as well as to size. Probably, smaller marginal lamina

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size reduced the arbitrary range of measurement points. Whatever the reason, methods producing the least variance are more desirable In describing carapace size, although sometimes less useful for comparing results with studies involving other methodologies. In the past, calipers for straight-line measurements have been used or suggested as a solution to the variability of over-the-curve measurements. Different curvatures of anterior and posterior carapace borders require that the calipers be held perpendicular to the body axis for correct measurements. Calipers would probably reduce the error, but only If anterior and posterior measurement points were agreed upon and used consistently. Even using calipers, each worker or research team should determine their own mensuration range. To Increase accuracy with present methods, measurement ranges or workers (obtained by repeated measurements) should be determined, tapes or calipers should be calibrated (we found a 1 m tape with a 9 mm error), and a single Individual should take all measurements unless team members are statistically compared over time (i.e., calibrate your field workers!). For work requiring accurate measurements, ectobiota Interfering with the measurement should be removed. Unless such actions are taken, carapace measurements will be only estimates of size and hence of only limited value In describing population parameters that are dependent upon accurate measurements. Slight error Is of little consequence If carapace length Is used only to aid in working out problems of transposed tag numbers on data sheets, or similar bookkeeping problems (e.g., is a particular tag known to be on a rather large turtle, or on a particularly small one?). The difficulty arises when field data are used to calculate growth rates, minimum size at sexual maturity, frequency distributions of size classes within a population, or similar population parameters. Any claim, Implied or stated, that a certain size as determined by field measurement is critical, when no indication has been provided by the Investigator concerning possible error or variance, requires some explanation to the reader. Mrosovsky. N. 1983. Conserving Sea Turtles. British Herpetological Society. Regent’s Park, London. C. RODERT SHOOP. Department of Zoology, University of Rhode Island, Kingston, RI 02881 USA, and CAROL RUCKDESCHEL, Cumberland Island Museum, PO Box 796, St. Mary’s, GA 31558 USA

Readers In the USA we reminded that your annual income taxes are due on 15 April. Thus, it is not too late to make a contribution to the MTN for the 1985 tax year. Contributions are tax-deductible to the extent allowable by law. Please make checks payable to: “Mercer University, Acct. No. WO3.421 0-90003.4211”.

Partial funding for MTN 36 was provided by the US Fish and Wildlife Service, the Cayman Turtle Farm (1983). Ltd.. Greenpeace Southeast and by Eric R. Martin and Katherine Frazer. The opinions expressed herein are those of the individual authors and are not necessarily shared by the Editorial Board, Mercer University, or other individuals or organizations providing financial support.

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