The Yearly Cycle: Vernal Pools

by Anna Autilio
Environmental Educator

Trout Lily (Erythronium americanum)
One of the most beautiful natural illustrations of the cycle of the year is found in the vernal pool. Often called “ephemeral”, these pools provide crucial, temporary homes for some distinct wild plant and animal species. Filling in the spring and drying in the summer, they track the changing temperatures and weather patterns without fail, year after year, for those who care to find them and peek inside!

The vernal pool at VINS went through a wet year in 2016-2017. Although it dried up in the summer, it filled again in the fall, and stayed filled through our warm yet snowy winter. A large snapping turtle even hibernated in the muddy bottom—she was seen catching some rays on an unusually warm December day.

Spring (May 2016)

Summer (July 2016)
Fall (October 2016)
Winter (December 2016)
Just this spring, the pool hosted some more diverse visitors, including another large snapping turtle to join the one who stayed the winter, a green frog (unusual at a vernal pool), several wood frogs, and even a pair of mallards and a barred owl, who were no doubt using the pool as a hunting spot.
At this time of year, the snapping turtle residents of our vernal pool have made their way uphill to lay eggs in specially dug burrows, sometimes quite far from the water. VINS has currently 6 different snapping turtle nests, which may contain each up to 50 eggs! These will hatch in September, and we will be on the look out for the tiny turtles making their way back downhill to the water.
Snapping Turtles (Chelydra serpentina)
If you are interested in learning more about vernal pools, and even helping scientists track them down, the Vermont Vernal Pool Mapping Project is for you! Run by the Vermont Center for Ecostudies and Arrowwood Environmental, this project aims to map the locations of all vernal pools in the state of Vermont. Almost 5,000 pools have already been mapped, but citizen scientists are still needed to confirm the location of potential pools, and identify the animals and plants species living within. Follow the link below to learn more:


  1. Anonymous on November 14, 2017 at 7:16 pm

    Always informative and interesting; I look forward to these blog posts.

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