Threatened Frogs Get A New Home In Mass. And Another Shot At Survival

An Eastern Spadefoot. Courtesy MassWildlife
An Eastern Spadefoot. Courtesy MassWildlife

A small frog with a big voice is starting to make a comeback in Massachusetts, thanks to some help from state scientists and student volunteers.

The eastern spadefoot is about 2 inches long, with a big head and yellow, cat-like eyes. The males have a distinctive mating call, which sounds something like a crow blowing its nose.

The spadefoot's numbers have dwindled in the state, mostly because of habitat destruction. The Massachusetts Division of Fisheries & Wildlife (MassWildlife) now lists the animal as one of three threatened amphibians in the state.

"They only breed under very specific conditions in very specific places, and those conditions don't always occur," said Brian Bastarache, who chairs the Natural Resources Management department at the Bristol County Agricultural High School and has a lead role in the spadefoot restoration effort. He said the frogs live only in loose, sandy soil, and spend most of their time underground.

"They spend all day in little underground burrows that they dig. They'll come out on a on a rainy, cool night in the spring, summer or fall to feed, but they'll only breed when there's one heck of a downpour and their pools fill up," Bastarache said. "If they don't have that, or you fill in that pool, that population is doomed."

An Eastern Spadefoot adult. Courtesy MassWildlife
An Eastern spadefoot adult. Courtesy MassWildlife

To give the threatened frogs a leg up, the state, along with students from the Bristol agricultural program and Westfield State University, dug artificial vernal pools in the Southwick Wildlife Management Area and stocked them with eggs, tadpoles and baby frogs that they had bred by hand. This "head start" approach can increase survival chances for transplanted species, said MassWildlife's Emily Stolarski.

The process, funded in part by the Massachusetts Outdoor Heritage Foundation and the biotech company Sanofi Genzyme, began six years ago, and the various eggs and froglets were transplanted from 2017-2019. When the spadefoots might actually breed was a big question mark, but the heavy rains in July gave Team Spadefoot reason to suspect that the frogs may have emerged from their burrows in a breeding kind of mood.

And sure enough, when MassWildlife conservation scientist Jacob Kubel visited the pools in July, he was welcomed with a symphony of mating calls.

Kubel found spadefoot tadpoles in one pool, and at least 30 breeding adults in another. Eggs and recently hatched tadpoles were confirmed at the latter pool a couple days later, said MassWildlife's Stolarski.

Conserving the frog is a high priority in the Connecticut Valley, Stolarski said, because centuries of human activity have altered habitat so extensively that biologists know of only three populations of eastern spadefoot there. Now, there is hopefully one more.

"Amphibians on the whole planet are just about in the worst shape of any vertebrate that we have," said Bristol's Bastarache, who points out that frogs like the eastern spadefoot have unique biochemistry that could possibly lead to innovative treatments for human diseases.

"We won't know if we let these things go extinct," he said. "Just about every single organism out there is one of these libraries of Alexandria. And when we let one go extinct, you know, we're just burning another library."

More Stories:

Headshot of Barbara Moran

Barbara Moran Correspondent, Climate and Environment
Barbara Moran is a correspondent on WBUR’s environmental team.



More from WBUR

Listen Live