THE EASTERN MASSASAUGA RATTLESNAKE IN NEW YORK ...

Current Range

THE EASTERN MASSASAUGA RATTLESNAKE IN NEW YORK: OCCURRENCE AND HABITAT MANAGEMENT Glenn Johnson and Alvin R. Breisch ABSTRACT

The eastern massasauga (Sistrurus catenatus catenatus) is currently known from two locations in New York State. Historic reports and scattered anecdotal information indicates they may have occurred or still occur in at least three other locations in the western part of the state. Monitoring efforts initiated in 1980 by the New York State Department of Environmental Conservation in one of the extant populations, the state-owned Cicero Swamp Wildlife Management Area, suggested a dramatic decline in population size has occurred since the 1960’s. In 1983, the massasauga was added to the state’s Endangered Species List. Within Cicero Swamp, a 2024 ha wetland complex, the massasauga is largely restricted to a 37 ha peatland dominated by the shrubs, mountain holly, (Nemopanthus mucronata) and highbush blueberry, (Vaccinium corymbosum). This peatland appears important for overwintering and gestation of massasaugas. Radiotracking studies indicate that, following spring emergence, few snakes remain in the closed-canopy peatland. The purpose of this study was to create gaps in the shrub canopy and determine whether massasaugas will use these gaps for feeding, basking or other activities. Sixteen 625 m2 plots were established in tall, dense shrub cover (mean height = 2.02 m, mean woody stem density = 26.55 stems/m2) in the winter of 1991. In each plot, woody stems were cut at ground level, piled in the plot centre, and burned. After one growing season, mean height of woody stems in cut areas was 0.52 m and mean woody stem density was 63.26 stems/m2. In cut and burned areas, mean height was 0.29 m and mean woody stem density was 41.04 stems/m2. Nine out of 89 (10.1%) above ground radiolocations in the peatland from nine individuals tracked in 1991 occurred in or around cleared areas. Cleared areas represent only 2.5% of the total peatland area, indicating a disproportionate use, and suggesting that vegetation manipulation may increase critical massasauga habitat. OCCURRENCE OF THE EASTERN MASSASAUGA IN NEW YORK

The earliest scientific writing that mentioned the eastern massasauga, in connection with New York State is by DeKay (1842) and he considered it extralimital in the state. Since that time, this snake has been reported from at least five discrete locations in the western half of the state. Currently, the eastern massasauga is known conclusively from only two locations in New York State (Figure 1): Cicero Swamp Wildlife Management Area (CSWMA) in Onondage County and Bergen-Byron Swamp in Genesee County. Perhaps the first description of the massasauga from New York was by Gebhard in 1853, who received a specimen taken from a white-cedar swamp, likely the Bergen Swamp, near the Town of Byron, Genesee County (Moesel, 1918). Moesel (1918) collected two specimens from the Bergen Swamp in June of 1917. Wright (1919) reported massasaugas as “not uncommon” from Bergen Swamp. Numerous sightings still occur from this area (Breisch, 1984; Johnson, 1990). Some of the earliest references to massasaugas at Cicero Swamp were reported by botanists (Wibbe, 1883; Rust, 1883). An earlier report (Macauley, 1829) refers to rattlesnakes from a variety of locations in New York including several towns in Madison and Onondaga Counties, Macauley appears to be describing timber rattlesnakes (Crotalus horridus), however the above locations are more likely habitat for massasaugas. Whiffen (1913) collected three specimens from Cicero for the New York Zoological Society; at that time the swamp was much larger, extending eastward into Madison County and northwest into the Stanley J. Hamlin Wildlife Management Area (formerly Clay Marsh). Massasaugas have not been reported in recent times from Madison County, where most of the remaining wetlands have been converted to agriculture or are otherwise only marginally suitable for massasaugas. Despite some verbal reports from area residents and the occurrence of some potentially suitable habitat, massasaugas have not been found in the Stanley Hamlin Marsh (Johnson, 1990). Cicero Swamp still supports a population (Breisch, 1984; Johnson, 1988, 1990) and has even received a degree of notoriety in the popular literature (Kaufield, 1969) which is thought to have contributed to unregulated collecting in the 1970’s. 48

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Bergen Swamp in Genesee County

* Cicero Swamp Wildlife Management Area in Onondaga County Historic or Purported Sites 0 Falconer site in Chautauqua County 0 Concord site in Erie County @ Riga site in Monroe County @ Rochester site in Monroe County @ Arcadia site in Wayne County @ Spring Lake site in Cayuga County 8 Madison County site adjacent to Cicero Swamp @ Stanley J. Hamlin Wildlife Management Area (formerly Clay Marsh) in Onondaga County

Figure 1. Extant, historic and purported massasuaga populations or sightings in New York State.

While bona fide museum specimens collected in New York exist only from these two extant sites (Reinert, 1978), historic reports and anecdotal information indicate they may have occurred at several other locations (Figure 1). Moesel (1918) reported a specimen from a site referred to as Featherbed Swamp, near Spring Lake in Cayuga County. Wright (1919) reported them from this area also and states local farmers and members of the Botanical Section of the Rochester Academy of Science have also seen them. While Featherbed Swamp appears on older Cayuga County maps and has been described botanically (Wiegand and Eames, 1925), recent visits to this area indicate extensive muck farming has completely altered the character of the site rendering it no longer suitable as massasauga habitat. Interviews with area farmers include no recollections or recent observations of massasaugas. There have been two unconfirmed sightings of massasaugas in the 1960’s and 1970’s at a peatland in the Town of Arcadia in Wayne County (Reixinger and Peterson, 1982). In addition, there are several reports of dogs from this area believed to have died from snake envenomation. Repeated visits by the Endangered Species Unit of the New York State Department of Environmental Conservation (DEC) and others in the 1980’s have failed to validate these claims. Over the periods 1876 - 1900 and 1941 - 1943, the peatland has been the site of extensive peat mining operations (Rynearson 1985). These operations radically altered the character of the peatland and may have contributed to the extirpation of the purported massasauga population. If the massasauga has been extirpated from the site, it is unlikely they could reestablish without a translocation programme. The Arcadia site is of interest because it appears to possess many habitat characteristics suitable for massasaugas. It consists of a basin containing an extensive floating bog mat at its north end and a series of Metro Toronto Zoo

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Current Range shrubby and open peatlands to the south. These peatlands are structurally and floristically similar to Cicero Swamp and offer numerous overwintering sites for massasaugas. The basin is bordered to the west and east by drumlins, that are primarily forested, interspersed with old fields and agricultural lands. A report exists for a sighting from the mid-1960’s in a sphagnum bog in the Town of Concord in Erie County. A visit by DEC personnel in 1982 did not uncover any evidence of massasauga occupancy (Reixinger, 1982). A return visit is planned for 1992. A 1985 report came from a commercial nursery near the Town of Falconer in Chautauqua County. In this instance, the description of the snake was reasonably conclusive, however it was killed and disposed of. It has been learned that this nursery received regular shipments of peat moss from Wainfleet Bog near Port Colbourne, Ontario and it is possible the snake’s origin was from such a shipment. Wainfleet Bog is a valid location for massasaugas in Canada (Weller and Parsons, Table 1. 1991). A site visit was conducted to the Falconer Summary of captures, recaptures and numbers marked of eastern site in 1992 by the first author and no suitable massasaugas in Cicero Swamp Wildlife Management Area over the period 1980-1991. habitat was observed. Finally, vague reports # captured # recaps prev. yrs Snake/hr exist from a large swamp east of Rochester and Year Number marked (inc. recaps)* a planned landfill site in the Town of Riga, both 1960 16 55a 0.28 in Monroe County. Site visits to the former area 1961 4 12 4 0.13 by both authors and several visits to the latter by 1982 0 1 1 0.02 the first author failed to uncover any 1983 1984 3 5b 2 0.16 massasaugas or suitable habitat. 1985 3 6 0 Extensive monitoring efforts for the 1986 3 3c 0 massasauga were initiated by the DEC in 1980 1987 30** 43 0 0.22 at CSWMA. These investigations suggested a 1988 22 54d 5(1987) 0.20 dramatic decline based upon a 92% reduction 1989 12 20 5 0.22 in capture success over a three year study 1990 10 25e 11 (Reixinger and Peterson, 1982). These results, 1991 6f 16 10 coupled with unregulated collecting and * Does not include radio locations. ** Snakes colour-marked only; scale clipping 1988-1991. conclusive evidence of only one other extant a. Twenty-two neonates also observed. population, led to the 1983 addition of the b. Two neonates also observed. massasauga to the New York State Endangered c. Five additional adults observed and not marked and five neonates also observed. Species List. Population monitoring has d. Twenty-five neonates also observed (3 broods). continued at CSWMA (Table 1) as well as the e. Nineteen neonates also observed (3 broods). Bergen Swamp site. In addition, studies are f. Two young-of-the-year also observed and not marked. underway at CSWMA investigating the spatiotemporal ecology via radiotelemetry, effectiveness of several habitat management schemes (see below), and the ecological genetics (in cooperation with Parks Canada) of the eastern massasauga. HABITAT MANAGEMENT IN CICERO SWAMP WILDLIFE MANAGEMENT AREA, NEW YORK INTRODUCTION

The Cicero Swamp Wildlife Management Area (CSWMA) is a 2024 ha wetland complex 15 km northeast of Syrcause, New York and is owned and managed by the New York State Department of Environmental Conservation. CSWMA is composed primarily of forested wetlands with lesser amounts of open ponds, marshes, old fields and shrubland. Within this wetland complex is a 37 ha peatland that is the primary habitat for the eastern massasauga. The peatland now resembles a shrub-carr, and was created by an intense fire that started in 1892 (LeBlanc and Leopold, 1992) and will hereafter be referred to as the “burn area”. It is dominated by the shrubs, mountain-holly (Nemopanthus mucronata), highbush blueberry (Vaccinium corymbosum) and black chokeberry (Aronia melanocarpa), with lesser amounts of black huckleberry (Gaylussacia baccata) and leatherleaf (Chamaedaphne calyculata). Tree species include black spruce (Picea mariana), American larch (Larix laricina) and European birch (Betula pendula), occurring as scattered individuals or small stands. The area is described in more detail by LeBlanc (1988). 50

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Current Range areas. In September of 1990, the number, diameter, height and species of all woody stems were recorded in each subplot. The number and species of all herbaceous plants were recorded also. These measurements will be monitored for the next five years in the subplots. Attempts to determine massasauga use of cleared areas were evaluated by periodic systematic searches and monitoring of radiomarked individuals. To evaluate the treated areas for small mammal abundance as a prey base, six trapping stations were established in and around each of the 16 plots. A similar number of traps were placed in another portion of the “burn area” equivalent in size and ecological conditions. Half of the stations consisted of two Museum Special snap traps and half consisted of one snap trap and one pitfall trap. Snap traps were baited with a mixture of rolled oats and peanut butter. Pitfall traps were set along downed logs or some other natural runway. Each trap was open for three nights. PRELIMINARY RESULTS AND DISCUSSION

Prior to cutting and burning, the mean height of overstory shrub species in the “burn area” was 2.02 m and the mean woody stem density was 26.55 stems/m2. By the end of one growing season (30 September 1991) the mean height of woody stems in cut only areas was 0.52 m and the mean woody stem density was 63.26 stems/ m2. These stems represented primarily stump sprouts from cut vegetation with little establishment of new woody vegetation. This observed regrowth rate is more rapid than that observed by LeBlanc and Leopold (1992); stem heights in their study ranged from 10-22 cm in less than two growing seasons. This may be reflective of different site conditions or annual weather patterns. Plot size in LeBlanc and Leopold’s study was 1.0 m2, substantially smaller than those of this study. Light levels would be expected to be higher in the larger plots and may account for differences in observed growth rates. In cut and burned areas, mean height was 0.29 m and mean woody stem density was 41.04 stems/m2. Here, revegetation is primarily via root suckering. Burned areas showed greater establishment of primarily winddispersed plants such as quaking aspen (Populus tremuloides) and thistles (Cirsiuim spp.) than cut only areas. Qualitative observations in midsummer 1992 indicate little additional height growth, suggesting burned areas will remain in a lower, less dense vegetative condition. Nine out of 89 (10.1%) distinct above ground radiolocations within the “burn area” of all nine implanted snakes occurred in or immediately adjacent to treatment plots. Cleared areas represent 2.5% of the total area of the “burn”. In addition, three of the six new sighting of untagged massasaugas for 1991 occurred in or near treated areas. One of these massasaugas was a gravid female who remained in the plot throughout most of the summer. Parturition or neonates were not observed. This may be as much a reflection of search effort bias or relative ease in searching newly-cleared areas as an increase in snake use of cleared area. These data are not conclusive nor are they statistically significant, however they suggest a disproportionate use. Over 1500 trapnights resulted in only seven potential prey captures for the two areas (three Sorex cinereus and one Lepus americanus in the treated area and three S. cinereus in the control). Clearly, at least at the time of the trapping session, small mammal abundance and diversity was low. This may be related to several factors including low availability of food sources, low degree of surface structure to provide suitable cover, or depth of the water table. Since many species of small mammals undergo periods of lowered abundance (Krebs, 1966; Terman, 1968) a similar round of trapping is planned for two time periods in 1992. The area selected for the vegetative treatments are centrally located within the “burn area” and typically are greater than 100 m from another cover type. In 1989, 300 trapnights in an area of the “burn” adjacent to another cover type (red maple, (Acer rubrum) swamp with a well-developed understory and ground cover) resulted in 13 captures of six species (G. Johnson, unpubl. data). Small mammals use the “burn area” for some activities, but appear to restrict these activities to the periphery. These results, and those of LeBlanc and Leopold (1992) suggest that the shrub canopy will rapidly recover following cutting. It has been suggested that one or more further cutting applications to the treated areas will significantly delay recovery. Burning will also delay this process but the extent of this delay awaits further monitoring. The burns described above did not significantly affect the peat substrate and cannot be compared to the extensive burns that occurred 100 years ago on this site. Cutting and burning are labour-intensive activities and demand a strong commitment by managers of this resource. Techniques to reduce this effort to achieve an

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Current Range early successional plant community in the “burn area” should be explored, including those that mechanically affect the substrate and the use of herbicides. FUTURE EFFORTS

Several projects related to massasauga management in New York are either underway or are in the planning stages. Populations at both CSWMA and Bergen Swamp will continue to be monitored. Return visits are planned for some of the other purported sightings as well as following up new leads. In cut and burned areas, 92.2% of the woody stems were browsed by white-tailed deer (Odocoileus virginianus) or snowshoe hares (Lepus americanus), while 40.0% of the stems in cut only areas were browsed. Herbivore browsing may contribute positively to the management strategy by maintaining a lower, more open condition within the treated areas. Conversely, plant responses to continued browsing of new stems may result in additional shoot growth creating a denser condition. To evaluate the effects of herbivore browsing on the management strategy, eight additional 625 m2 plots were established in the “burn area” in 1992. These plots were cut and burned as before. In each plot a 5 m x 5 m herbivore exclusion fence was established. The area within each plot enclosed by each fence was 50% cut and burned and 50% cut only. The relative growth rates of the shrub stems will be evaluated as before. An experiment designed to test the effectiveness of the herbicide glyphosphate (Roundup) is proposed for late summer, 1992. A 500 m2 plot will be selected and species composition, stem density, basal area, and canopy height will be described. This plot will be arranged into a 5 x 4 completely randomized block design with each subplot 5 m2. Each of the four rows will have four treatments and a control. The four treatments include 1) manual cutting with stem removal, 2) manual cutting followed by wick application of herbicide to the cut stems, 3) foliar spray with backpack sprayer, and 4) foliar spray followed in two weeks by manual cutting. Vegetational response will be monitored annually over a five year period. ACKNOWLEDGMENTS

Numerous individuals contributed to the habitat management work including M. Ingraldi, M. Keefe, W. Burns, P. Hess, T. Wills, D. Hampton, R. Baker, W. Halpin, K. Brewer, M. Connerton, E. Balko, M. Kallaji, M. King, R. Fewster, Burnet Park Zoo chapter of the Explorer’s Club, many students at the S.U.N.Y. College of Environmental Science and Forestry and the Liverpool High School, and inmates from the Georgetown Correctional Facility. Funding was provided by the New York State Department of Environmental Conservation, S.U.N.Y. College of Environmental Science and Forestry, the American Wildlife Research Foundation, and the Central New York Wildfowlers. D. Leopold provided useful comments on earlier versions of this manuscript. LITERATURE CITED Breisch, A. R. 1984. Just hanging in there: the eastern massasauga, in danger of extinction. The Conservationist Nov.-Dec. pp. 35. Costanzo, J. P. 1989. Effects of humidity, temperature and submergence on survivorship and energy use in hibernating garter snakes, Thamnophis sirtalis. Can. J. Zool. 67:2486-2492. DeKay, J. E. 1842. Zoology of New York Part III: reptiles and amphibians. Albany, New York 99 pp. Fitch, H. S. 1970. Reproduction cycles of lizards and snakes. Univ. Kansas Mus. Nat. Hist. Misc. Publ. No. 92, 24 pp. Hubbell, S. P. and R. B. Foster, 1986. Commonness and rarity in a neotropical forest: implications for tropical tree conservation pp. 205-231. (M. Soule, ed.) Conservation biology: the science of scarcity and diversity. Sinauer Associates, Sunderland, Mass. 584 pp. Johnson, G. 1988. Population status of the eastern massasauga at the Cicero Swamp Wildlife Management Area, Onondaga County, New York. Final report - summer 1988. Prepared for the New York State Dept. Environ. Cons. Mimeo. 10 pp. Johnson, G. 1990. Eastern massasauga project - Cicero Swamp Wildlife Management Area. Summary of activity - 1990 Field season. New York State Dept. Environ. Cons. Mimeo 24 pp. Johnson, G. 1991. Eastern massasauga project - Cicero Swamp Wildlife Management Area. Summary of activity - 1991 field season New York State Dept. Environ. Mimeo 29 pp. Kauffield, C. 1969. Snakes: the keeper and the kept. Doubleday and Co. Garden City, N.Y. 248 pp. Ketchledge, E. H. 1963. Interview with a local resident, Mr. John Joss of Cicero, unpubl. rept. 5 pp. Krebs, C. J. 1966. Demographic changes in fluctuating populations of Microtus californicus. Ecol. Monographs 36(3): 239273.

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Current Range LeBlanc, C. M. 1988. Vegetation dynamics in a central New York shrub-carr 94 years after fire. MS Thesis S.U.N.Y. Coll. Environ. Sci. For. Syracuse, New York 94 pp. LeBlanc, C. M. and D. J. Leopold. 1992. Demography and age structure of a central New York shrub-carr 94 years after fire Bull. Torrey Bot. Club. 119(1): 50-64. Macauley, J. 1829. Natural civil and statistical history of the State of New York. Vol. 1 (p 441 and pp 513-517). Moesel, J. 1918. The prairie rattler in western and central New York. Copeia 1918(58): 67-68. Reinert, H. E. 1978. The ecology and morphological variation of the massasauga rattlesnake (Sistrurus catenatus). MS Thesis Clarion State Coll. Clarion, Pennsylvania. 173 pp. Reixinger, P. 1982. Field trip to East Concord bog, New York State Dept. Environ. Cons. Memo 1 pp. Reixinger, P. and A. Peterson, 1982. Biology and status of the massasauga (Sistrurus catenatus) at Cicero Swamp 1980 1982. New York State Dept. Environ. Cons. Mimeo 27 pp. Rust, M. 0. 1883. Apropos of Cicero Swamp. Bull. Torrey Bot. Club 10(6): 66-67. Rynearson, M. 1985. Zurich and Bond Preserve Swamp News 25(1): 8 pp. Terman, C. R. 1968. Population dynamics pp. 412-450. in Biology of Peromyscus (Rodentia). J. A. King (ed.) Spec. Publ. Amer. Soc. Mamm. 2:1-593. Wiegand, K. M. and A. J. Eames. 1925. The flora of the Cayugo Lake Basin, New York: vascular plants. Cornell Univ. Sta. Memoir 92. 491 pp. Weller, W. F. and H. J. Parsons, 1991. Status of the eastern massasauga Sistrurus catenatus in Canada. Committee on the Status of Endangered Wildlife in Canada. Unpubl. Rep. 38 pp. Wheeler, B. D. 1988. Species richness, species rarity and conservation evaluation of rich-fen vegetation in lowland England and Wales. J. Appl. Ecol. 25:331-353, Whiffen, E.. T., 1913. The massasauga in New York State. Bull. Zool. Soc. N.Y. 16(55):949-950. Wibbe, J. H. 1883. Notes from Central New York. Bull. Torrey Bot. Club. 10(4):46-47. Wright, A. H. 1919. The snakes of Monroe and Orleans County, N.Y. Copeia 1919(67): 10-12.

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