Wet weather triggers freshwater bodies teeming with fairy creatures

After years of dry weather, a wet winter and spring has filled the Island's natural landscapes with an abundance of seasonal freshwater vernal ponds teeming with fairy shrimp and other woodland creatures, ecologists and state officials said.

The ponds have unlocked dormant eggs of the tiny crustacean fairy shrimp and a proliferation of amorous amphibians — spotted salamanders, wood frogs and spring peepers, a diminutive frog with a mighty high-pitched mating call that signals winter's end.

"This year has been phenomenal," John Turner, a conservation policy advocate for the nonprofit Seatuck Environmental Association, said one warm April night at a vernal pond in Nassau County. "To me, spring peepers are the harbinger of spring. I don't know if they could be much louder."

Vernal ponds, also called vernal pools, can be found in the hilly undeveloped areas of Long Island, from Montauk Point to the Long Island pine barrens farther west in Suffolk to a few miles from the Queens border. Though the bodies are small, state law protects vernal ponds as wetlands of "unusual local importance."

The ponds are an underappreciated and often overlooked natural habitat, local ecologists said.

Vernal ponds "don't get much attention because they are pretty small and are sometimes hidden," said Kevin Jennings, the state Department of Environmental Conservation's regional manager for ecosystem health.

At the gated Greentree Estate in Manhasset, a mile off the Long Island Expressway, up a dirt road that winds behind North Shore University Hospital and is tucked back in the woods, there are a series of shallow depressions filled with water.

As the sun goes down at Greentree, the chirps of spring peepers, which can fit on the head of a nickel, turn into a chorus, joined by a quack-like mating call of the wood frog. Somewhere in the thigh-high water are spotted salamanders, who've left behind tennis ball-sized egg masses suspended just below the surface, which Turner described as feeling "like a ball of snot. Like Jell-O."

As snow melts and rain falls in February and March, the depressions fill up with water from a few inches to a few feet. After the snow melts, the first life to appear are fairy shrimp, a crustacean that grows up to an inch long. Their dormant eggs, called cysts, can survive for years out of water.

Then come the amphibians. The salamanders use the ponds to reproduce before heading upland into the forest for most of the year, including the endangered Eastern tiger salamander and more common spotted salamander, as well as the spring peepers and wood frogs. Later in the year, other amphibians will call the vernal ponds home. Fowler's toads and gray treefrogs will come in May to June, as well as pickerel frogs, bull frogs and green frogs.

By July, many of the vernal ponds are typically gone, the water evaporated and sucked up by trees and other plant life through transportation, Turner said.

That dry period is important for the life cycle of the vernal ponds. Ponds with water year-round would likely harbor fish that feast on the eggs of the shrimp and amphibians.

But drought-like conditions in recent years lowered groundwater levels, which made many vernal ponds not appear at all or dry up quicker, according to Jennings.

"A lot of vernal ponds were dry for most of the active parts of the year, when amphibians would be breeding in there," Jennings said. This year, he said, there were many more vernal ponds.

There's no formal count of vernal ponds on Long Island. The last mapping effort was done in the 1980s in Nassau County and in the 1990s in Suffolk County, when the state was trying to track wetlands.

"The biggest threat is the threat of development. There's the potential they're being lost because they're so small," Jennings said. Even if the pool itself gets protected, it does little good if upland forest is destroyed. Salamanders, in particular, use the pool for breeding but then spend most of their lives in the woods.

Turner also said prolific sewering in some areas has drawn down the aquifer by sending groundwater out to the oceans and bays. That has lowered water tables and diminished vernal ponds.

"As we pump more water up out of the aquifer, and ultimately discharge it out to the Atlantic Ocean, invariably we’ll have a drawdown of the aquifer. And these vernal ponds and many other types of wetlands will take it on the chin," he said.

Seatuck has done annual monitoring of vernal ponds and the amphibian population at Greentree Estate, and hopes to do a formal assessment of the amphibians to establish trends.

"The goal is to further quantify the population so we can assess it over time," said Enrico Nardone, executive director of Seatuck. He called the estate "certainly one of the largest populations of these micro-ecosystems left in Nassau County."

Chris Paparo, a naturalist and manager of Stony Brook University's Marine Sciences Center in Southampton, also has taken note of the more abundant vernal ponds this year. Along with the appearance of skunk cabbage and return of osprey, the sound of spring peepers is a sign of the changing season.

He has noticed the change in his backyard. When he bought his house 15 years ago in Calverton, he said, "The first spring was deafening at night from all the peepers."

After four or five years, things got drier. The vernal ponds and bogs in his backyard almost completely disappeared. It got quiet.

But for "the first year in quite a few years," the vernal ponds — and spring peepers, woodfrogs and other amphibians — are back, Paparo said. "We keep the windows open at night. It's the song of spring."

By David M. Schwartz

dschwar1@newsday.comschwartznewsNY

David Schwartz covers environmental issues. A native Long Islander, he's worked at Newsday since 2013.