Vernal Pools: Immerse Yourself in the Mystical Habitat

March 8, 2023

By Kim Sherwin, Interpreter

Come for a walk with me to a mystical place found in many of your Metroparks. This particular habitat is found in wooded areas, covered with water through part of the year. Many visitors see them as nothing more than wet, lifeless, puddles in the woods. They couldn’t be more wrong.

A walk along the Landscape trail in Stony Creek Metropark will bring you up and down hills, along Stony Creek and through woods, fields and wetlands. The landscapes you experience along this trail are due to the glaciers that were present over 13,000 years ago. In early spring, as you amble up one particular hill, pause on top to catch your breath. To the right stretches the rolling hills of a prairie, tall grasses waving in the breeze. Before you, at the bottom of this steep hill, is a seemingly lifeless wooded puddle. As gravity pulls your feet downhill, the silence is filled with peeps, trills and … clucking chickens?

This unique wetland is here because a chunk of ice separated from the main glacier, was covered with outwash, and slowly melted to reveal a bowl-like shape. This particular pool is close to the water table, so fills with water each spring, then becomes bone-dry in late summer. A vernal pool is formed.

A step onto the boardwalk above the water, gives you the ability to immerse yourself within this mystical habitat. The sounds become deafening. Yes! There is life here, but more than most people realize. Over 550 animal species have been found to use these vernal pools.

Four animals in particular, the wood frog, spotted salamander, blue-spotted salamander, and fairy shrimp tell us that it is indeed, a vernal pool. These four species rely on this crucial habitat to complete their life cycles. Because these wetlands dry up each year, vernal pools are fish-free. Fish predators are not a worry in this nursery!

A look around shows there are no chickens to be seen, but instead, a small reddish-brown, masked frog is found. The Wood Frog is said to sound like the clucking of a chicken, or the quack of a duck. The musical chorus that vibrates your ears are the peeps from Spring Peepers, the upward trill of Chorus Frogs, and the quacking of Wood Frogs. Lie down on the boardwalk and look closer into the water. As you lie still, the water comes alive. Small swimming, floating, and squirming animals reveal themselves. Fairy shrimp, dragonfly and damselfly nymphs, predacious water beetles, giant water bugs, salamander larvae and tadpoles are just some of the animals you can see.

Because this type of wetland is so variable and dries up during the year, it’s a wetland that is not well understood or protected under current wetland laws. If you are interested in learning more about vernal pools and the animals that rely on them, or would like to help research and conserve them, check out the Vernal Pool Patrol. This is a community science program started by the Michigan Natural Features Inventory to get the public involved in gaining a better understanding of the status, distribution and ecology of vernal pools in Michigan.

Keep an eye on the Metroparks events calendar for vernal pool discovery programs and salamander migration programs to get immersed in these mystical habitats.

Sources:

13,000: https://project.geo.msu.edu/geogmich/glacial.html

Vernal pool: https://mnfi.anr.msu.edu/abstracts/ecology/Vernal_Pool.pdf

550 Animal Species: https://vppartnership.iescentral.com/menus/animals.html

Peeps from Spring Peepers: https://www.youtube.com/watch?v=O4nZ13F1rYw

Water Comes Alive: https://mivernalpools.com/news/article/New-Video-Explores-Vernal-Pools.html

Vernal Pool Patrol: https://vernal-pool-patrol-mnfi.hub.arcgis.com/pages/about

Vernal Pool Discovery Programs: https://web1.myvscloud.com/wbwsc/mihuronclintonwt.wsc/search.html?display=detail&FMID=60218551&Module=AR&_csrf_token=310e301294b80e41ea677dd77cc2b5b8ee83154373e00502c0e474511479d26b

Salamander Migration Programs: https://web1.myvscloud.com/wbwsc/mihuronclintonwt.wsc/search.html?display=detail&FMID=60216022&Module=AR&_csrf_token=66d7f17fe0462a62b64a398d4caae48b6c2942278c9a6e00034ca54ee7dd807b