NEW YORK — Warren Pond in southern Connecticut, bordered by shady oaks and maples, is a lovely place to fish for bass or sunfish. Or, if the mood strikes you, to hunt the Eastern red-spotted newt.
Why one would want to hunt newts is a valid question. But for Evan Grant, who was stalking the banks of Warren Pond this month, scanning the water through polarized sunglasses, the answer is that many species of salamander in the United States, including the newts he was seeking, may be on the brink of a deadly fungal assault, much like one that has devastated some frog and toad populations worldwide.
In 2013, scientists discovered that a fungus called Batrachochytrium salamandrivorans, commonly known as Bsal, was attacking salamanders in Europe. Researchers later determined that species in the United States were vulnerable to the infection. And earlier this year, the US Fish and Wildlife Service temporarily banned the import of 201 species of salamanders that pose a danger of carrying the fungus into the United States.
In the meantime, the US Geological Survey is monitoring vulnerable salamander populations to catch any early signs of infection. So far, researchers have not found evidence of Bsal.
Grant, a research wildlife biologist with the agency’s Amphibian Research and Monitoring Initiative, has spent much of the last month in New England, catching red-spotted newts, swabbing their skin to check for infections, and sending samples to the National Wildlife Health Center in Madison, Wisconsin.
In mid-May, he put on rubber boots and shouldered a long-handled dip net to explore the pond, in Newtown, Conn., with Adrianne Brand, a wildlife biologist who is also with the initiative.
Newts, and salamanders in general, do not simply grow from egg to adult the way mammals or reptiles do. They have several stages, from egg to larva to adult, and in any given species, they may skip a stage, change whether they live in water or on land, grow lungs or stick with gills. Some absorb oxygen through their skin, and skip both lungs and gills. Newts, in particular, are like ecological utility infielders, switching habitats and physiology depending on what is needed for the game of staying alive.
The two researchers found no newts in the pond, so they moved on to a swampy patch in the woods of Paugussett State Forest, down a hillside from a suburban cul-de-sac. The water, about knee high, was dark with detritus and bracketed by thickets.
After a few minutes of swishing his net through the water, which ran over the top of his boots, Grant called out, “Yo! Newt!’’
The catch was about 3 inches long, identifiable as a male because of the shape of its tail and rough patches on the inside of its hind legs, with a dark greenish brown color and red spots that warn predators of toxins in the skin.
He swabbed the skin and snipped off the ends of the swabs for testing.
The two biologists also stalked newts at ponds in Vermont’s Green Mountain National Forest, trapping as many as 30 in small nets or wire traps resting on the lake bottom.
The United States is considered a global treasure trove of salamander diversity, and the USGS study is concentrating on sampling a few areas that have species like the newt, known to be vulnerable to Bsal.
Salamanders may serve as a kind of early warning system for environmental problems, and they are deeply embedded in forest ecosystems, so their reduction could have unpredictable consequences.
Material from the Associated Press was used in this report.
