Current Range

THE EASTERN MASSASAUGA RATTLESNAKE IN NEWYORK: OCCURRENCE AND HABITAT MANAGEMENT

Glenn Johnson and Alvin R. Breisch

ABSTRACTThe 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 atleast three other locations in the western part of the state. Monitoring efforts initiated in 1980 by the New York StateDepartment of Environmental Conservation in one of the extant populations, the state-owned Cicero SwampWildlife Management Area, suggested a dramatic decline in population size has occurred since the 1960’s. In1983, 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 peatlanddominated by the shrubs, mountain holly, (Nemopanthus mucronata) and highbush blueberry, (Vacciniumcorymbosum). This peatland appears important for overwintering and gestation of massasaugas. Radiotrackingstudies indicate that, following spring emergence, few snakes remain in the closed-canopy peatland. Thepurpose of this study was to create gaps in the shrub canopy and determine whether massasaugas will use thesegaps 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, woodystems were cut at ground level, piled in the plot centre, and burned. After one growing season, mean height ofwoody stems in cut areas was 0.52 m and mean woody stem density was 63.26 stems/m2. In cut and burnedareas, 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 clearedareas. Cleared areas represent only 2.5% of the total peatland area, indicating a disproportionate use, andsuggesting that vegetation manipulation may increase critical massasauga habitat.

OCCURRENCE OF THE EASTERN MASSASAUGA IN NEW YORKThe 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 fromat least five discrete locations in the western half of the state. Currently, the eastern massasauga is knownconclusively 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 aspecimen 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 Yorkincluding several towns in Madison and Onondaga Counties, Macauley appears to be describing timberrattlesnakes (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 wasmuch larger, extending eastward into Madison County and northwest into the Stanley J. Hamlin WildlifeManagement Area (formerly Clay Marsh). Massasaugas have not been reported in recent times from MadisonCounty, where most of the remaining wetlands have been converted to agriculture or are otherwise onlymarginally suitable for massasaugas. Despite some verbal reports from area residents and the occurrence ofsome 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 adegree of notoriety in the popular literature (Kaufield, 1969) which is thought to have contributed to unregulatedcollecting in the 1970’s.

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Extant Sites

l 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 inCayuga County. Wright (1919) reported them from this area also and states local farmers and members of theBotanical Section of the Rochester Academy of Science have also seen them. While Featherbed Swamp appearson older Cayuga County maps and has been described botanically (Wiegand and Eames, 1925), recent visits tothis area indicate extensive muck farming has completely altered the character of the site rendering it no longersuitable as massasauga habitat. Interviews with area farmers include no recollections or recent observations ofmassasaugas.

There have been two unconfirmed sightings of massasaugas in the 1960’s and 1970’s at a peatland in theTown of Arcadia in Wayne County (Reixinger and Peterson, 1982). In addition, there are several reports of dogsfrom this area believed to have died from snake envenomation. Repeated visits by the Endangered Species Unitof the New York State Department of Environmental Conservation (DEC) and others in the 1980’s have failed tovalidate these claims. Over the periods 1876 - 1900 and 1941 - 1943, the peatland has been the site of extensivepeat mining operations (Rynearson 1985). These operations radically altered the character of the peatland andmay have contributed to the extirpation of the purported massasauga population. If the massasauga has beenextirpated 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 formassasaugas. It consists of a basin containing an extensive floating bog mat at its north end and a series of

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shrubby and open peatlands to the south. These peatlands are structurally and floristically similar to CiceroSwamp and offer numerous overwintering sites for massasaugas. The basin is bordered to the west and east bydrumlins, 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). Areturn visit is planned for 1992. A 1985 report came from a commercial nursery near the Town of Falconer inChautauqua County. In this instance, the description of the snake was reasonably conclusive, however it waskilled and disposed of. It has been learned that this nursery received regular shipments of peat moss fromWainfleet Bog near Port Colbourne, Ontario and it is possible the snake’s origin was from such a shipment.Wainfleet Bog is a valid location formassasaugas in Canada (Weller and Parsons,1991). A site visit was conducted to the Falconer

Table 1. 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

habitat was observed. Finally, vague reports period 1980-1991.

exist from a large swamp east of Rochester and Year Number # captured # recaps prev. yrs Snake/hr

a planned landfill site in the Town of Riga, both marked (inc. recaps)*

1960 16 55a - 0.28in 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 - - - -

massasaugas or suitable habitat. 1984 3 5b 2 0.16

Extensive monitoring efforts for the 1985 3 6 0 -

massasauga were initiated by the DEC in 19801986 3 3c 0 -

at CSWMA. These investigations suggested a1987 30** 43 0 0.221988 22 54d

dramatic decline based upon a 92% reduction 5(1987) 0.20

1989 12 20 5 0.22in 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.

conclusive evidence of only one other extant ** Snakes colour-marked only; scale clipping 1988-1991.

population, led to the 1983 addition of thea. Twenty-two neonates also observed.b. Two neonates also observed.

massasauga to the New York State Endangered c. Five additional adults observed and not marked and five neonates

Species List. Population monitoring has also observed.

continued at CSWMA (Table 1) as well as thed. Twenty-five neonates also observed (3 broods).e. Nineteen neonates also observed (3 broods).

Bergen Swamp site. In addition, studies areunderway at CSWMA investigating the

f. Two young-of-the-year also observed and not marked.

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

INTRODUCTIONThe 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 EnvironmentalConservation. 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 easternmassasauga. 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 inmore detail by LeBlanc (1988).

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areas. In September of 1990, the number, diameter, height and species of all woody stems were recorded ineach subplot. The number and species of all herbaceous plants were recorded also. These measurements will bemonitored for the next five years in the subplots.

Attempts to determine massasauga use of cleared areas were evaluated by periodic systematic searchesand monitoring of radiomarked individuals. To evaluate the treated areas for small mammal abundance as aprey base, six trapping stations were established in and around each of the 16 plots. A similar number of trapswere placed in another portion of the “burn area” equivalent in size and ecological conditions. Half of the stationsconsisted of two Museum Special snap traps and half consisted of one snap trap and one pitfall trap. Snap trapswere baited with a mixture of rolled oats and peanut butter. Pitfall traps were set along downed logs or some othernatural runway. Each trap was open for three nights.

PRELIMINARY RESULTS AND DISCUSSIONPrior 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) themean 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 woodyvegetation. This observed regrowth rate is more rapid than that observed by LeBlanc and Leopold (1992); stemheights in their study ranged from 10-22 cm in less than two growing seasons. This may be reflective of differentsite conditions or annual weather patterns. Plot size in LeBlanc and Leopold’s study was 1.0 m2, substantiallysmaller than those of this study. Light levels would be expected to be higher in the larger plots and may accountfor 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 wind-dispersed 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 willremain in a lower, less dense vegetative condition.

Nine out of 89 (10.1%) distinct above ground radiolocations within the “burn area” of all nine implantedsnakes occurred in or immediately adjacent to treatment plots. Cleared areas represent 2.5% of the total area ofthe “burn”. In addition, three of the six new sighting of untagged massasaugas for 1991 occurred in or neartreated areas. One of these massasaugas was a gravid female who remained in the plot throughout most of thesummer. Parturition or neonates were not observed. This may be as much a reflection of search effort bias orrelative ease in searching newly-cleared areas as an increase in snake use of cleared area. These data are notconclusive 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 cinereusand one Lepus americanus in the treated area and three S. cinereus in the control). Clearly, at least at the time ofthe trapping session, small mammal abundance and diversity was low. This may be related to several factorsincluding low availability of food sources, low degree of surface structure to provide suitable cover, or depth of thewater 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 aregreater than 100 m from another cover type. In 1989, 300 trapnights in an area of the “burn” adjacent to anothercover type (red maple, (Acer rubrum) swamp with a well-developed understory and ground cover) resulted in 13captures of six species (G. Johnson, unpubl. data). Small mammals use the “burn area” for some activities, butappear to restrict these activities to the periphery.

These results, and those of LeBlanc and Leopold (1992) suggest that the shrub canopy will rapidly recoverfollowing cutting. It has been suggested that one or more further cutting applications to the treated areas willsignificantly delay recovery. Burning will also delay this process but the extent of this delay awaits furthermonitoring. The burns described above did not significantly affect the peat substrate and cannot be compared tothe extensive burns that occurred 100 years ago on this site. Cutting and burning are labour-intensive activitiesand demand a strong commitment by managers of this resource. Techniques to reduce this effort to achieve an

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early successional plant community in the “burn area” should be explored, including those that mechanicallyaffect the substrate and the use of herbicides.

FUTURE EFFORTSSeveral 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 areplanned 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 (Odocoileusvirginianus) 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 opencondition within the treated areas. Conversely, plant responses to continued browsing of new stems may result inadditional shoot growth creating a denser condition. To evaluate the effects of herbivore browsing on themanagement strategy, eight additional 625 m2 plots were established in the “burn area” in 1992. These plots werecut and burned as before. In each plot a 5 m x 5 m herbivore exclusion fence was established. The area withineach plot enclosed by each fence was 50% cut and burned and 50% cut only. The relative growth rates of theshrub stems will be evaluated as before.

An experiment designed to test the effectiveness of the herbicide glyphosphate (Roundup) is proposed forlate summer, 1992. A 500 m2 plot will be selected and species composition, stem density, basal area, and canopyheight will be described. This plot will be arranged into a 5 x 4 completely randomized block design with eachsubplot 5 m2. Each of the four rows will have four treatments and a control. The four treatments include 1) manualcutting with stem removal, 2) manual cutting followed by wick application of herbicide to the cut stems, 3) foliarspray with backpack sprayer, and 4) foliar spray followed in two weeks by manual cutting. Vegetational responsewill be monitored annually over a five year period.

ACKNOWLEDGMENTSNumerous 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 ofEnvironmental Science and Forestry and the Liverpool High School, and inmates from the GeorgetownCorrectional 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 theCentral New York Wildfowlers. D. Leopold provided useful comments on earlier versions of this manuscript.

LITERATURE CITEDBreisch, 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. SinauerAssociates, 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 - 1990Field 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 fieldseason 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): 239-

273.

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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 fireBull. 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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