Vernal Ponds -- Miraculous and Imperiled
by Mary Ann Mulvihill-Decker
(Reprinted with permission)
Under the canopy of the hardwood forest, melted snow combined with cool spring rains and at last the vernal pond appeared. Songbirds came to bathe and find insects and a rabbit took a long, much needed drink. A great egret stood nearby, having returned from its long flight north. The tracks of a fox were evident along the pond edge. A meandering turtle stopped to feed. The calls of the wood frogs were unmistakable. Tiny crustaceans and invertebrates emerged from the mud in the spring thaw and grew stronger in the pool, free from the predation of fish. Soon dragonflies would hover above the still water while salamanders mated below.
Vernal ponds or pools are tremendous genetic storehouses of life, protecting the next generation of biodiversity in the forests in which they exist. Commonly found in upland areas of forest with overhanging trees which provide a reliable substrate of leaf litter, vernal ponds are usually less than an acre in size and often very much smaller.
Since the retreat of the glaciers, these small depressions fill with water in late winter and spring. What appeared unremarkable weeks earlier now becomes miraculous. Life explodes as eggs hatch and new generations of countless species begin their next cycle, one that has been repeated thousands and thousands of times. Meanwhile, hibernating toads, frogs and turtles awaken nearby and are drawn once again to the pond, as are mammals and birds which find sustenance in the ephemeral waters.
Vernal ponds are breeding grounds and nurseries for a plethora of creatures. They are a microcosm of the natural world around us. Because vernal ponds have no inlet or outlet, they have no fish. This provides a vastly safer place for vulnerable animals to be born than in coastal plain ponds, streams or estuaries.
Named from the Latin vernalis for spring, these pools are temporary. In most years, they mainly dry out in the heat of summer. Yet beyond our view, the many dormant lifeforms survive, within deep humus accumulated over countless centuries. Some may re-fill during autumn rains, but the cooler conditions generally ensure that the life hidden below remains dormant until the following year. In times of drought, vernal ponds may not appear at all. But evolutionary processes over millenia have provided that only the fittest individuals of each species have successfully reproduced. Vernal pond species endure remarkable extremes: from bitter cold to extreme heat, and from a fully aquatic environment to a total lack of water.
Pond-breeding amphibians rely on the seasonal hydroperiod of vernal pools. Tiger, spotted, marbled, blue-spotted and Jefferson’s salamanders all breed in vernal ponds. Their gill-breathing larvae hatch from eggs and live within the water before reaching their juvenile stage. Once transformed, the salamanders emerge onto the land. Fairy Shrimp are obligate vernal pond breeders, that is they cannot exist without them. Their eggs remain in the drying pools after the adults die, only to be born when spring again returns.
Air-breathing snails and Fingernail Clams burrow into the mud when the pond disappears, and reappear only when water does, living their entire lives in vernal ponds.
Legislation for protection of wetlands varies from region to region and decade to decade. Thankfully since the 1970s, New York does have fairly robust laws to safeguard wetlands from developers and other threats. Vernal ponds however, have fallen through the cracks. According to the New York Natural Heritage Program, vernal ponds “seldom meet the size criteria for state-regulated wetland”. Those remaining, a fraction of what once existed, are in continual peril. One of the biggest problems is educational: most people don’t understand or even know about vernal ponds. And because they are visible only part of the year, they are unrecognized, underappreciated and quickly destroyed forever by bulldozers and careless developers, road-building, dumping and logging. Other significant threats include recreational overuse such as All-Terrain Vehicles, run-off from fertilizers, pesticides, herbicides, silt, septic and other pollution. Nearby pavement increases that risk. Road salt and other particulates can smother the delicate life within the pool and alter its chemistry to lethal effect. Many vernal ponds have become trash dumps or have been filled in senselessly.
Vernal ponds on public preserve land are theoretically safer than on private land. However, in Sag Harbor on Long Island, in the Long Pond Greenbelt and Great Swamp area, there are numerous vernal and other ponds. An ancient gem of New York State, this area provides habitat for abundant rare flora and fauna.
According to Dai Dayton, President of Friends of the Long Pond Greenbelt, the area “is one of the most ecologically diverse areas in New York State and is supposed to be a protected natural habitat.” Although preserved by millions of taxpayer dollars and many years of effort and negotiation, this sanctuary is greatly threatened due to a current plan by the electric company to install an underground transmission cable through this critical habitat. They propose clearing land in Great Swamp to facilitate “Horizontal Directional Drilling” which is expected to produce gallons of “liquid waste/slurry” daily. They admit the possibility of accidental “frac-outs”, that is releasing this slurry of unknown chemical composition into the wetlands, as well as the need to “remediate” endangered Eastern Tiger Salamander (Ambystoma tigrinum) habitat and vernal ponds. Extinction can never be remedied. Once destroyed, vernal ponds can neither be recreated nor replicated. Vernal ponds cannot be moved.
Many citizens are currently beseeching the Southampton Town Board and Suffolk County officials to deny underground rights-of-way to PSEGLI. An alternative route exists along roadways for this infrastructure, which they claim is needed for increased electrical demands. Desecration of vernal ponds and endangered salamander habitat in preserved land to save the company money
is short-sighted, ignorant, unethical and dangerous. In addition, Great Swamp, part of the Peconic Bioreserve, overlies the groundwater divide of the South Fork of Long Island and its finite and precious aquifers. It is at the center of several parcels declared critical for groundwater protection.
We are all bearing witness to a worldwide biodiversity crisis. Vernal ponds need protection more than ever. For not only are all the vulnerable and remarkable species that live and breed within them imperiled, but so are many of those other species that we love and cherish which benefit from the countless lifeforms within vernal ponds. Spread the word!