With all the snow and cold temperatures we are still experiencing it may be hard to imagine that warmer weather is just around the corner. However, now that March is underway, it will only be a few short weeks until spring officially arrives and the movement of some very special species will begin. While many bird species will start their long journey back to the northeast from places such as Costa Rica where our affiliates have been banding migrants, a variety of non-feathered species will begin traveling through our forests to find their annual breeding pools. The quiet peace of winter will soon be gone and the bombarding cackles of Wood frogs, roaring peeps of hundreds of Spring Peepers and rustling of leaf litter on the forest floor by a number of salamander species will mark the actual start of spring and relief of Old Man Winter’s grip.
Jefferson Salamander eggs attached to vegetation
As the snow melts and spring rains begin to fall, depressions in the landscape will fill with cold water and create a safe place for amphibians to court and lay their eggs without the threat of predatory fish. Several species of “mole” salamanders will begin to move in mass from their subterranean tunnels towards these breeding sites and may travel several hundred feet to get to water, which for a salamander is quite a trek! Jefferson and Blue-spotted salamanders (Ambystoma jeffersonianum and Ambystoma laterale respectively) will be the first to visit the vernal pools or small ponds in early March as temperatures rise and will sometimes make their way through snow to get to the pool, even if only the edges of the water are ice free. Spotted salamanders (Ambystoma maculatum) will follow a few weeks after and are often seen migrating in great numbers during the first nights of 40°+ temperatures and rain.
Jefferson Salamander (Ambystoma jeffersonianum)
Once these salamanders hit the water, it is a frenzy of males enticing the few females within the pool to accept their spermatophore. After the females accept a spermatophore, they will lay their eggs in clumps, allowing them to rest at the bottom of the pool or attaching them to sticks or vegetation within the water. The outer layer will quickly absorb water and give the eggs that characteristic “jelly” coating, making it difficult for predators to ingest the eggs. As the eggs develop, some symbiotic algae species will begin to grow on the egg masses as well, utilizing the carbon dioxide and waste created and in turn providing oxygen for the developing embryos.
Blue-Spotted salamander (Ambystoma laterale)
Spotted Salamander (Ambystoma maculatum)
Spotted Salamander eggs. Note the milky appearance
Pool breeding frogs do things a little differently. As the temperatures rise and the ground begins to thaw, so do the Wood frogs (Rana sylvatica) and Spring Peepers (Pseudacris crucifer). And yes they literally thaw. These frogs create natural antifreeze in order to prevent their cells from forming ice crystals, which would cause death, and remain frozen throughout the winter.
Male Spring Peeper (Pseudacris crucifer) singing his song
While these frogs have this ability, don’t be thinking you can catch a frog and throw it in the freezer! Once the frogs are all warmed up, they too will migrate in mass to the pools to breed from early March into April. The males will call in attempts to attract the females to them. If a female gets into grasping range, the male will jump on her back and squeeze her around the belly to force her to extrude her eggs; this is often referred to as amplexus. As the female releases her eggs, the male will fertilize them. Wood frogs will sometimes deposit their eggs in communal aggregates, particularly in larger pools, and several studies have shown that the large groups of masses maintain higher temperatures and in turn may develop faster than small masses by themselves. Spring peepers on the other hand, deposit their eggs individually underneath vegetation and debris.
Male Wood Frog (Rana sylvatica) amplexing a female
As the temperatures slowly climb and warmer rains come our way, throw on your rain jacket and grab a flashlight or headlamp. Be careful where you step, but get out some rainy evening and enjoy these cool creatures make their move to wet areas within the woods or near wood edges. Nothing compares to seeing hundreds of salamanders, not normally seen any other time of the year, creep along the forest floor towards open water or hearing thousands of Peepers screaming their high pitched “peep” around a pool. Furthermore, remember these are species are sensitive to disturbances, and the Jefferson and Blue spotted salamanders in particular are of Special Concern in New York State.
It is important not to disrupt these natural areas in which these important species breed. Amphibians of all kinds are valuable indicator species, and their presence signifies a healthy habitat. Amphibian populations around the world are unfortunately declining due to habitat loss or degradation of habitat quality. So help the salamanders and frogs this breeding season by letting them do their thing and protect the area in which they utilize from other forms of use. Also, stay tuned as we will be keeping an eye on the migrations throughout our area and will post updates as well.
Elyse Henshaw
Conservation Technician
Photos © Twan Leenders
