What are vernal pools and why are they important to Vermont wildlife?

Vernal pools look like giant puddles and are often found in the woods in early spring until early summer. They often completely dry out by summer. Because they are isolated and temporary, many amphibian species can successfully reproduce and thrive, without their eggs and young being eaten by fish.

Amphibians known to regularly use vernal pools for breeding in Vermont include wood frog, spring peeper, spotted salamander, and red-spotted newt. These species all migrate from surrounding forests to vernal pools to mate and lay eggs in early spring. The amount of living material (biomass) contained in all the salamanders in a forest can exceed the total biomass of all the birds, and in some forests, of all small mammals as well.

vernal pool in forest

It’s very important to protect the first hundred feet of forest surrounding a vernal pool.

 

What can landowners do to protect these special places?

The first hundred feet or so from the pool are particularly important and can be sensitive to management activities. This area can have high densities of adult and immature amphibians, and its condition can have large impacts on the water quality of the pool.

Another 500 feet from the pool is important habitat for adult amphibians, though they will commonly venture up to three times as far.

Here are some things to keep in mind if you are trying to protect a vernal pool on your land:

  • By keeping machinery out of the pool and its edges and avoiding felling trees into the pool, you
    can limit physical alteration of the pool itself.
  • Retaining a closed canopy above the pool will prevent premature warming and drying. In
    surrounding upland habitat, maintaining a significant canopy will keep a cool, moist, forest floor
    for dispersing amphibians.
  • Leaving logs on the woodland floor will provide critical moisture havens.
  • Operating heavy machinery only when the ground is completely frozen or completely dry can
    minimize deep ruts and the creation of “population sinks,” pools that may be attractive to
    reproducing amphibians but will not lead to the survival of their offspring.
  • Consulting a professional forester about management around these habitats is recommended.

So the next time you see a broad-winged hawk (an amphibian connoisseur) flying through your woods, you may just find yourself thinking about moist logs on the forest floor, the shade of the canopy, wood frogs, salamanders, and vernal pools.