What better day to celebrate vernal pools than March 21st – the International Day of Forests. Vernal pools are those temporary spring flooded areas in your forests. They are known by many names – ephemeral pools, intermittent wetlands, spring wetlands – but whatever you do, don’t call them a puddle!
Puddles are unreliable; sometimes they appear, sometimes they don’t. We can’t reliably predict where they are going to be. Vernal pools on the other hand are rather dependable, they predictably appear with a seasonal rhythm – arriving and departing at the same general time and place, sometimes for thousands of years.
Vernal pools are usually found in forests, away from streams and rivers. This separation creates a safe predator-free habitat for certain species, like wood frogs and mole salamanders, for all or part of their life cycles. They also bolster fish populations up by preventing runoff from entering nearby lakes and contribute to the water levels of larger water bodies in the lowlands. The amphibian species that rely on vernal pools provide food for a number of bird species, eat insects, and (because of their absorbent skin) help us monitor the quality of some of our provinces freshwater.
Ontario Nature is working with a number of groups to map vernal pools across the province. This project will contribute greatly to our knowledge of these poorly-understood ecosystems and the species that occur within them.