RICHMOND — The enigmatic Eastern spadefoot toad is the focus of a collaboration involving the Richmond Rural Preservation Land Trust, the University of Rhode Island and several agencies and conservation groups.
Spadefoots are considered to be in decline in Connecticut and Massachusetts and in Rhode Island, and a single known breeding population remains in two pools in Richmond. The goal of the project is to expand the toads’ breeding habitat and increase the population.
Spadefoots are named for the projections bottoms of their hind feet which enable them to drill into the sediment where they spend their days buried, emerging at night. They have several additional distinguishing features, including cat-like eyes with vertical pupils and smooth skin with tiny red bumps on their backs. The toads also make unique calls that sound like crows.
Nancy Karraker, associate professor at the University of Rhode Island’s Department of Natural Resources Science, said while the spadefoot toad is abundant in some parts of the eastern U.S., its population is tenuous in Rhode Island, mainly due to a loss of breeding habitat.
“These toads breed in the most ephemeral of all vernal pool-type ponds, pools that maybe hold water for three weeks, four weeks at the most,” she said. “They get in there, they can lay their eggs, the eggs hatch within a day or two and then the tadpoles can make it to metamorphosis in three weeks.”
The pools may be vital breeding habitat for the toads, but to most people, they’re just large puddles to be filled in. To make matters worse, the spadefoot appears to be rather picky about when and where it breeds.
“Conservationists who care about reptiles and amphibians are in a bit of a panic about this, because in addition to the challenge of a few breeding sites remaining, they don’t breed every year,” Karraker said. “They only breed in the years when we get giant amounts of rainfall in May, June or July and as far as I know, they haven’t bred for four years in the state… The clock is ticking in terms of how long we’re going to be able to keep them around in the state unless we do something.”
In a presentation to the Richmond Town Council at the April 16 meeting, Land Trust Chair Suzanne Paton, who is also a biologist with the U.S. Fish and Wildlife Service, explained that new breeding pools will be dug on the Land Trust’s Scudder Preserve, which is located near the existing pools.
“It’s within dispersal distance,” she said. “Since they spend the winter in the forest, we assume that they’re somewhere around.”
The project involves creating two new pools which, it is hoped, the toads will accept, thereby expanding their tiny breeding range.
“One is 40 feet in diameter and it’s probably going to be about 12 to 15 inches deep, and the other pool will be 50 feet diameter and 12 or 15 inches deep,” Karraker said. “So that’s very shallow and very small, the idea being, if we built two pools now and others through time of different sizes and different depths, we’ll get just the right level of water and frequency that the pool holds water that will satisfy our particular spadefoot toads.”
Funding for the project, about $20,000 so far, has been cobbled together from the Land Trust, the Conservation Stewardship Collaborative and the University of Rhode Island.
“A bunch of different organizations have offered up bits of money and people and other resources, excavators and forklifts and all the stuff we need to make this happen,” Karraker said.
Leading the project is Massachusetts wetlands restoration consultant Tom Biebighauser who has designed more than 20 spadefoot breeding pools in his home state. Working with a team of volunteers, Biebighauser will dig the new pools on the Scudder Preserve from May 13 to May 15.
“Those pools will be within about 400 yards of that last remaining breeding population,” Karraker said. “Once we get the new pools built, we will continue to monitor those and the existing, natural pools every single time we get significant rainfall, and hope that the toads breed this year, for one, and secondly, if they breed, they find our pools.”
If the toads breed, the research team may also seek permission from the Rhode Island Department of Environmental Management to move some of the tadpoles to the new pools. Most frogs and toads return to the pools where they were born in order to breed.
“I’m just really excited that we’ve got enough funding to move forward,” Paton said. “I’m keeping my fingers crossed that we’ll get breeding toads. That would be great."