March 11, 2011
(and How You Can Help)
They’re secretive, slimy, kind of cute, and up to nine inches long. Some are polka dotted. You’ve probably never seen them, since they spend 11 and a half months of the year hidden away—under leaf mold or a log and in the winter months, inside the burrow of a shrew or mole. But one night a year, after most of the snow has melted and the temperature hovers around 40 degrees, following a day of steady rain, the salamanders emerge en masse and travel several hundred feet or more to a small pool in the woods.
The males enter the water first, dropping packets of sperm, which the females then absorb into their cloacas. The mating ritual occurs in the pool over the next several nights, after which the females deposit their eggs, resembling clusters of clear grapes. The adult salamanders, which are believed to live up to a decade—the young can take up to two years to mature—then travel in dribs and drabs back to their woodland lairs.
Unfortunately, on that initial, sex-charged journey to the pool, many of them don’t make it. Thousands are squashed by cars as they cross the road, following migration patterns established over a millennia and oblivious to the barriers created by humans. Furthermore, the mole salamanders, as these amphibians are called, along with wood frogs are completely dependent on these fragile woodland pools for their survival. They don’t breed anywhere else.
The high rates of road kill, forest fragmentation, destruction of the vernal pools, along with pollution of the water by chemical-laden run-off, have severely impacted the populations of three of the four species of mole salamanders found in our region: the drab-looking Jefferson’s, the blue-spotted, whose skin resembles antique enamel, and the smaller, white streaked marbled salamander (which actually breeds in the fall) are all listed as species of special concern in New York State. A fourth species, the spotted salamander, is still fairly common, as is the wood frog (whose duck-like quacks resonate from the pools in early spring). The Jefferson’s and blue-spotted salamanders interbreed, and most of the ones found here are hybrids.
In an effort to raise public awareness of the need to protect these threatened animals, Laura Heady, the New Paltz-based biodiversity outreach coordinator at the New York State Department of Environmental Conservation’s Hudson River Estuary Biodiversity Program, started a pilot project three years ago in which volunteers search the roadways during the migratory “Big Night” both to identify crossing points where large numbers of salamanders and frogs are getting killed and protect the animals by carrying them across the road. (Still rather chilled, the amphibians are slow moving, enabling them to be easily picked up.)
Right around now, Heady starts sending out e-mail blasts to the growing list of interested participants whenever there’s a rainy day, as a heads-up for what might turn out to be the Big Night. Last year, it occurred on March 22 and in 2009, on March 26; some years the amphibians may be on the move over several nights.
At a well-attended talk at the Tivoli Library held last Thursday, March 2, Heady noted that last year more than 75 volunteers were stationed at approximately 30 crossings in eight counties. Nine salamander species and seven species of frogs and toads were identified, of which 2,847 were alive and 1,429 dead. (Other species of salamanders and frogs also breed in the woodland pools, but not exclusively so.) Heady said that as more people participate and important crossing points are identified, she is hopeful that eventually formal road blocks could be set up, monitored by the Boy Scouts or other community group, with perhaps a municipal transportation department providing reflective signs to alert motorists to slow down or stop for the amphibian crossings.
Such programs have been set up in other states, a few of which have wildlife management programs in place for these populations. In 2006, for example, Massachusetts launched a conservation plan for mole salamanders under its Natural Heritage and Endangered Species Program, mapping their presence in the state, noting the threats to the existing populations and specifying better forestry practices and other steps and procedures that would help conserve the species.
Home to 85 percent of the state’s amphibian species, the Hudson Valley is a “hotbed of diversity” that warrants a particular conservation effort, especially given its dense population and development pressures, Heady said. Of particular concern are the diminishment of large forests and the threat to their specialist species—those who cannot survive elsewhere–as well as the destruction of wetlands. A recent loosening of federal standards has put isolated wetlands smaller than 12.5 acres outside the protection of the law, she noted.
Particularly at risk are woodland pools. Also called vernal pools, these small, isolated wetlands—under two acres–fill up in the spring from the snowmelt, dry out in mid summer, and fill up again in the fall. (It’s a race for the salamanders to lay their eggs early enough in the spring so that the hatchlings have time to develop before the pool dries up in July or August.) Isolated from other waterways, the pools can’t support populations of predaceous fish, which makes them ideal nurseries for salamander eggs and larvae (distinguished from tadpoles by their external gills, which resemble fringe-like ruffs). Lacking any kind of protection and mostly unmapped, woodland pools are fast disappearing.
Saugerties-based naturalist Spider Barbour, who has been tracking the salamanders for years, said he has unfortunately witnessed the destruction of several productive woodland ponds. “People do things on their land without knowing what they’re doing,” he said. “Here in Saugerties, on Platteclove Road, somebody took all this heavy equipment and totally gouged out one of the nicest vernal pools. It was a buttonbush swamp, which is one of the rarest type of wetlands. He cleared out everything, leaving only muddy banks.”
Barbour said another property owner, off West Saugerties Road, did the same to a red maple-black gum swamp, also a vernal pool. “She wanted a beach,” he said, noting the formerly beautiful spot is now an algae-infested pond. Besides ignorant property owners, woodland pools are at risk from new development.
Heady said preservation of woodland pools and the surrounding forest is not only key to the future survival of the mole salamanders, but also to a host of other species under stress from climate change. “We need wildlife corridors so that species can move to higher elevations” as their local habitat changes, she said. Fragmenting the forest not only traps and wipes out wildlife populations, but also might have detrimental effects on human health: Heady cited a study by the Carey Institute of Ecosystems, located in Millbrook, that found forests broken up into patches of five acres or less lead to increased incidences of lyme disease (the disturbed land benefits the white-footed mouse, a key host of lyme).
Woodland pools are in essence the coral reefs of the forest. Leaves fallen into the pools are the basis of a rich food web, starting with algae and larvae from the invertebrates, which munch on the vegetation. Other species, from spotted turtles to ribbon snakes to herons, feed on the invertebrates, which include the inch-long fairy shrimp. The pools also act as “micro-watersheds,” with each acre of wetland storing up to 1.5 million gallons of flood water—a particularly valuable feature given the heavier downpours occurring in the warming climate, Heady said.
Developers who save the pools but destroy the surrounding forest aren’t doing much good, she added. She cited a study that found in order to conserve the salamanders’ habitat, the woods around the pool must be left untouched for a minimum radius of 100 feet; only 25 percent of the land encompassed in the next 750 feet should be developed.
Since there is no impetus at the federal or state level to conserve woodland pools, it’s up to the municipalities to adopt zoning that protects forestlands and wetlands as part of their open space planning, Heady noted. Two examples are New Paltz and Rhinebeck. She said Putnam County officials have erected “go slow” signs near turtle crossings.
Putting on rain gear and heading out with a flashlight on the Big Night is a great way to get initiated into the mysterious world of the salamanders and learn about the abundance of life in the woodland pools. If you’re interested in helping out in this year’s Big Night, contact Laura Heady at 256-3061 (e-mail is ltheady@gw.dec.state.ny.us) Visit www.dec.ny.gov/lands/5094.html to see pictures of the salamanders and download the data collection form.
Since the animals’ skin must remain moist and is extremely sensitive, never pick up an amphibian unless your hands are clean, free of lotion or any other chemical residue.
Naturalist Steve Chorvas, who has come up with impressive counts the last two years in his native Saugerties, said he wears a reflective vest and head light. He recommends driving very slowly along a rural road that’s adjacent to wetlands, such as the stretch of 32 north of Saugerties. The salamanders are difficult to spot at first: “They don’t look like much. They’re just little forms, and usually they’re not even moving,” noted Barbour. Don’t get discouraged if you spot mostly road kill: counting and identifying the dead animals has a positive value, given the lack of information, noted Chorvas.