Every spring, when the weather warms up to at least 40 degrees, the snow is almost all melted and the ground is starting to thaw, a remarkable event known as Big Night occurs. On a warm, rainy evening all the amphibians in our area, including frogs and salamanders, migrate from the forest (where they spent the winter), to their vernal pools to breed. At least 80% of them will return to the pool in which they were born.
A wood frog venturing out at night
A vernal pool is a shallow depression in the ground that fills with water in the spring from melting snow and rain and will dry out in the summer. This temporary existence means fish, who would gobble up the eggs and babies, cannot live in them. Vernal pools are critical breeding habitat for amphibians and are crucial for maintaining health and balance in many forest ecosystems.
The spring migration often involves crossing a road or two, which puts the animals at risk. As you drive near wetlands on rainy spring nights, keep an eye out for wood frogs and salamanders on the road. Sounds of spring peepers and croaking wood frogs means that the breeding season has started, and the amphibians are on the move.
Among the many amphibians migrating, the spotted salamander is a common sight in New England. These salamanders can range in size from one inch to six inches. They have striking black bodies adorned with bright yellow spots. Interestingly, these beautiful creatures are poisonous to predators, which helps protect them in the wild. Once the male spotted salamanders reach the vernal pool, they dance and sway to attract a mate. The females will lay a white or clear mass of 10-250 eggs and attach it to vegetation.
Wood frogs are also a key player in this springtime migration. Once they reach the vernal pools, they seek mates and communicate through quacking sounds. A male wood frog will attach himself to a larger female that is full of eggs. As they swim around the pond, the female releases her eggs and the male fertilizes them.
Once the eggs have been laid, the frogs and salamanders quickly return to the woods they came from, only visiting water again to breed. The eggs have a short window of opportunity to develop, hatch and mature into their adult form before the vernal pool dries up. As you enjoy the beauty of spring in Connecticut, remember to appreciate the incredible journey of these amphibians during Big Night! Besides being cute, amphibians are important because they eat tons of insects and are a food source for many larger animals.
How to help:
If you see an amphibian in the road, move it with a wet leaf to the side in the direction it was heading. Cover your flashlight with red cellophane.
Want to learn more? Join us for our own “Big Night” with the amphibians at Hilltop Farm, Friday, April 4 from 6:30-8 p.m. For more information or to register for the program, go to our website: Hilltopfarmsuffield.org and click on the Events tab.