The Carlisle Mosquito Online

Friday, April 26, 2002


Become a vernal pool sleuth

It's that time of year again, when the spring peepers start singing, the wood frogs begin quacking and salamanders start migrating. Yes, it's vernal pool season! So grab your boots and net and follow the sound of the wood frog chorus to your nearest vernal pool.

You may have heard about these little wetland gems that are found in every town in the state, but did you know that there might be as many as fifty in Carlisle? The definition of a vernal pool depends on whom you talk to, but the Division of Fisheries and Wildlife ­ Natural Heritage & Endangered Species Program (NHESP) defines a vernal pool as a temporary pond that: 1) serves as important wildlife habitat for specific species and 2) does not contain fish. Certain species of frogs, toads, salamanders, insects and crustaceans breed in vernal pools and nowhere else.

Finding vernal pools where you live may be easiest during warm days or at night in the spring, when the breeding chorus of wood frogs can be heard at great distances. Recently, the NHESP made finding vernal pools a little easier with the publication of the Massachusetts Aerial Photo Survey of Potential Vernal Pools. This aerial survey identified more than 2,900 potential vernal pools across Massachusetts. Many of these potential pools may in fact be certifiable vernal pools, but because aerial surveys are not foolproof, there are undoubtedly errors and omissions. Some pools due to small size or conifer cover may have been missed. Conversely, a number of potential pools may actually be shadows of large trees, large rocks, pools that dry up too quickly or pools with fish. Despite the inevitable errors associated with the Massachusetts Aerial Photo Survey of Potential Vernal Pools, it is still an extremely useful tool to locate potential pools in our town.

If you are interested in certifying vernal pools in Carlisle, or have questions about a potential vernal pool of your own, contact the Carlisle Conservation Commission at 1-978-369-0336 or e-mail If you would like more information about vernal pools and the certification process, check out Please remember that landowner permission must be obtained prior to any field investigations on private property.

2002 The Carlisle Mosquito