SALAMANDERS, TOADS AND FROGS: AMPHIBIA
Amphibians are often grouped together with reptiles under the term “herps” despite the fact that they are in quite different Classes: Reptilia for snakes and turtles, and Amphibia for salamanders, frogs and toads. A total of 12 species of amphibians have been recorded on the island. Several species have extremely limited ranges here; the most fascinating being the Eastern spadefoot (Scaphiopus holbrooki). These animals only breed when their ephemeral breeding basins fill during heavy rainfall in the spring or early summer. It can be many years between breeding events.
The historical deforestation of the main island that occurred in the 1700-1900 period largely eliminated the habitats of most forest-dwelling species, especially salamanders, all three species of toads, and Gray Treefrog. Also, insecticide spraying in the 1940s and 1950s could have had a severe impact on frog and toad populations. No verfied records of Gray Treefrog exist, but these treefrogs were heard calling in two different locations in the early summer of 2022. They could easily be transported to the island and may breed here one day. Naturalists should be listening in May and June for their calls and search for tadpoles to verify breeding, should it occur.
Some frog species prey on others or on others’ tadpoles. Unfortunately, American Bullfrogs are such a predator and have become a problem in many ponds. Bullfrog tadpoles have been introduced both knowingly and inadvertently from nurseries both on and off the island. Large populations have been present in Edgartown, Vineyard Haven and West Tisbury for some time, and the species is established in Chilmark.
Surprisingly, there appear to be no amphibians at all on Nomans Land Island National Wildlife Refuge. Their absence is probably because the entire island was a sheep pasture and virtually treeless for most of the 1800s. Most of the ponds there now were man-made in the 1920s and apparently no frogs were introduced. If there ever were salamanders, toads or frogs in the small natural ponds, they appear to have died out.
Allan Keith; edited by Luanne Johnson July 28, 2022
REFERENCES FOR AMPHIBIANS
DeGraaf, R. M. and D. D. Rudis. 1983. Amphibians and reptiles of New England.
University of Massachusetts Press. 85 pp.
Lazell, J. D. Jr. 1976. This broken archipelago – Cape Cod and the islands, amphibians
and reptiles. The New York Times Book Co. 260 pp.
Web Resources:
https://www.mass.gov/service-details/amphibians-and-reptiles-in-massachusetts Maintained by the Massachusetts Division of Fisheries and Wildlife, this page provides a county-level checklist for reptiles and amphibians in the state.
https://massherpatlas.org/amphibians_reptiles/index.html Based on a statewide atlas project coordinated by the University of Massachusetts, 1992-1998. Includes some life history information and identification aids.