INVENTORY OF AMPHIBIANS AND REPTILES AT FIRE ISLAND NATIONAL SEASHORE
Natural Resource Report NPS/NCBN/NRTR—2010/378

Robert P. Cook
National Park Service
Cape Cod National Seashore
Wellfleet, MA 02667
Robert_Cook@nps.gov

David K. Brotherton and John L. Behler
Department of Herpetology
Wildlife Conservation Society
Bronx Zoo
Bronx, NY 10460-1099
dkb4112@yahoo.com


September 2010

U.S. Department of the Interior
National Park Service
Natural Resource Program Center
Fort Collins, Colorado
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Executive Summary

Under a National Park Service (NPS)/Wildlife Conservation Society Cooperative Agreement, we inventoried amphibians and reptiles on Fire Island National Seashore (FIIS) from March through September 2002, with additional turtle surveys in spring 2003. Six sampling methods were used; anuran calling surveys, visual encounter surveys, coverboards, turtle trap surveys, minnow trap surveys, and drift fencing. We also recorded animals encountered incidentally, including an eastern hog-nosed snake observed in 2007.

We recorded 12 species: 2 migrant and 10 resident. The 10 resident species represent 90% (9/10) of the species believed to have historically occurred on FIIS, plus a recent introduction, American bullfrog. These 12 species include two anurans, seven turtles, and three snakes. Fowler’s toad, snapping turtle, and northern black racer were the most abundant and widely distributed species in each taxonomic group. “Listed” species recorded were the eastern mud< turtle (NY Endangered)), eastern hog-nosed snake, spotted turtle, and eastern box turtle (NY Special Concern), and two migrant sea turtles, loggerhead (NY and federally Threatened) and leatherback (NY and federally Endangered), that washed up dead on the beach. Of the methods used, incidental encounter recorded 10 of 12 species, followed by visual encounter survey (7), turtle trap survey (5), drift fence (4), coverboard and minnow trap survey (2), and anuran calling survey (1). Eleven species were recorded in upland habitats and nine in wetland. By tract, the combined Watch Hill-OPWA tract has the greatest resident species richness, eight species, followed by the Lighthouse tract, with six species recorded.

Fire Island has relatively few species of amphibians and reptiles compared to “mainland” Long Island. The naturally-depauperate herpetofauna of FIIS is the result of geographic isolation, limited freshwater habitat, and harsh environmental conditions. Of the 10 resident species known to have occurred historically, seven appear stable in terms of population trend. Of the remaining three, Fowler’s toad may be less common or at least underwent a decline in recent decades from which it has mostly recovered. The southern leopard frog has been extirpated and the eastern hog-nosed snake, last documented at FIIS in the 1970’s, was not recorded in 2002 or 2003. However, an incidental observation by NPS staff in 2007 indicates it is present, but extremely rare. These three species have declined regionally, due to habitat loss and pesticide use. Their decline on FIIS is likely due partly to these factors, plus those natural factors noted above that limit recolonization. In spite of these limitations, FIIS is an important site, especially for reptiles, with four of the resident species present listed by New York State as either Endangered or Special Concern. Because many of the stressors that are negatively impacting these species regionally do not operate at FIIS, populations within the park are relatively well protected and FIIS plays an important role in helping to preserve the region’s herpetofaunal diversity.

While a detailed plan for monitoring is beyond the scope of this inventory, the results suggest that a program based on anuran calling surveys, time or spatially constrained surveys, turtle trapping, and monitoring freshwater wetland water quality would be the most useful for generating quantitative data for trends analysis. Further work on eastern mud turtle, spotted turtle, eastern box turtle, and eastern-hog-nosed snake should be a high priority.

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