by Rebecca Chillrud
April 10, 2020
The call of the spring peeper (Pseudacris crucifer crucifer) is one of the region’s iconic signs of spring’s arrival. One of the first frogs to call and breed during this time, many people are familiar with this critter’s shrill peep—it can emit one peep per second, filling the air around their springtime ponds with a loud chorus of sound.
Though peepers may be the most recognizable frog out in the early spring, they’re not the only ones getting a head start to breeding season. The wood frog’s (Lithobates sylvaticus) mating season starts with the first warm spring rain and generally runs from March through May. Its call is much less piercing than the peeper’s—instead, males make low quacking or chuckling calls.
Both species breed and lay their eggs in vernal pools: ephemeral forest ponds, blanketed in leaves from a healthy forest, that appear when they’re fed by melting snow, rain or groundwater. These pools only stay wet for about seven months out of the year, but in that time, they host a wealth of animals. Because the pools aren’t directly connected to a waterway, they’re free from the fish that would otherwise prey on amphibian eggs and larvae.
Wood frogs lay egg masses made up of 1,000 to 3,000 eggs in the vernal pool. The eggs’ mass will flatten and float to the surface, camouflaged by the green jelly surrounding the eggs. The eggs take between a week and a month to hatch, depending on the temperature—eggs laid earlier in the season, when the weather is colder, will take longer.
The tadpoles metamorphose into frogs within two months of hatching. Outside of breeding season, they’ll spend most of their time silent and solitary, in forests and wetlands throughout the Chesapeake Bay watershed.
Interested in listening for frog calls in your area? You can become a FrogWatch volunteer! Data collected by FrogWatch is used to help inform the development of environmental protection and amphibian conservation strategies. Visit their website to register for an online training session and get started.