By Ted Watt Gazette Contributing Writer
It has happened every year, since the glaciers melted and forests returned to New England. And it will happen again this year, from now to mid-April in our area.
When the snow is largely melted in the woods and it starts to rain during the day, keep your eye on the temperature. If the rain continues and it remains above 40 degrees as darkness descends, it’s Big Night for the Pioneer Valley’s spotted salamanders.
The eight- to nine-inch, jet black and canary yellow-spotted amphibians will leave their woodland habitats and crawl to temporary spring pools (also known as vernal pools) where they mate and lay their eggs.
In the pools they dance—sinuously, seductively—males drawing females to their prepared sperm packets deposited on the pool bottoms. Courted females pick up the sperm, fertilizing their egg mass internally. The females then search out a twig—not too shallow, not too deep—on which to attach their clear, jellied masses of eggs.
The eggs slowly develop in the chilled water. The top of the water will freeze, but the masses, if placed properly, will escape. Depending on rains, however, the water level may drop, occasionally exposing the eggs and killing a whole year’s hatch. It’s risky in the short run, but the salamanders’ ancestral memories breed long-term success.
Upon hatching, the creatures’ carnivorous larvae wiggle out of the egg masses. They devour water fleas and midge larvae, and are preyed upon by water tigers and red-spotted newts. It’s a fine balance. Enough survive and metamorphose into adults by midsummer to carry on the species.
Over the years vehicle traffic began to affect the population—significantly fewer salamanders made it to the pools. The amphibians protect themselves from predators with a lima bean-shaped poison gland under the jaw on right and left. Their black and yellow coloring serves as a warning of the poison to other animals. But as they cross our roadways they have no defense against passing vehicle tires.
That’s why the Henry Street salamander tunnels in North Amherst were constructed. The first of their kind in the nation, these structures (just south of the junction with Pine Street) were installed in 1987 by the Town of Amherst’s Public Works Department with the cooperation of Cowls Lumber (the landowner), and the aid of the Massachusetts Audubon Society, the Fauna and Flora Preservation Society, the Hitchcock Center for the Environment and many volunteers.
The crossing from their upland habitat above Henry Street to their vernal breeding pools below has been greatly altered. The tunnels enable the spotted salamanders to cross under the road risk-free. If you’re in North Amherst and have a free moment, stop and take a look at these structures. They’re worth seeing any time of year.
Don’t miss our favorite Pioneer Valley amphibians on Big Night. When the conditions are right, put on a head lamp, pile on your warm and waterproof clothes and make your pilgrimage. You may be out for hours in the cold, wet darkness looking for the salamanders. If you find them, perhaps you will be able to save some of them from the tires.
Ted Watt is an educator/naturalist at the Hitchcock Center for the Environment.
Earth Matters, written by staff and associates of the Hitchcock Center for the Environment at 845 West Street, Amherst, appears every other week. For more information, call 413-256-6006, or write to us.Click here to return to full list of Earth Matters articles.