By E. Faye Ferrall

A wise man once said things are not often what they appear. Indeed, in the world of spring pools, bogs, and depressions there is more than meets the eye. Vernal pools, as defined by biologists, are virtually teaming with life of varied forms. In these coastal plains of Virginia, they are often right in our backyard. These spots are a bit of heaven-on-earth for nature livers and home of some very interesting animals including frogs, turtles, and salamanders.

Vernal pools are sometimes difficult to classify. Generally, they are pools that fill with water during winter months and dry up during the summer. They are not spring fed, but collect the rains of autumn and winter and support a wide variety of wildlife which depends on the temporary pools to carry out their life cycles.

To qualify to be a true vernal pool, scientists have listed the criteria of life forms that must make use of these special habitats. These animals are called "obligates" and in the Northern Neck of Virginia area include mole salamanders, named so because they live in burrows, and also spotted and marbled salamanders. Further north in Virginia's tidal plain, other species occur such as the wood frog, fairy shrimp, and the endangered tiger salamander.

The animals inhabiting these unique habitats make seasonal use of the pools at varying times depending on the species. The animals return to the vernal pools from underground burrows or from their homes under surrounding leaf litter to feed, seek out mates, and lay eggs. An event called "big night" is an exiting one for nature lovers, wildlife ecologists, and biologists. Navigating by the smell of algae back to the waters of their birth, salamanders will follow internal and external clues governed by temperature, humidity, and air pressure to leave their burrows and return to the pool. It is unfortunate that much habitat has been interrupted by roadways, and many migrating animals are killed every year during big night migrations.

Members of the Virginia Herpetological Society throughout the state have ongoing programs with teachers, students, and other private citizens to help monitor and protect the various pool inhabitants. These efforts range from careful long-term studies of the populations to the actual scooping up animals from the road during mass migration events.

One vernal pool in the Northern Neck supports at least nine species of amphibians including spring peeper; green and gray treefrogs; leopard and pickerel frogs; and three species of salamander. Some of these animals have been detected because of the ongoing study of the site over a period of several years. Monitoring of this and other sites may turn up even more species previously unrecorded by scientists.

A monitoring program can answer many questions that scientists have about the health of our environment. For instance, an area of much concern has been the decline in population size of various amphibian species throughout the world. Monitoring programs may help to determine the cause of this sudden decline and what it means in terms to the overall health of the environment. Recording which species are affected in Virginia and their relationship to the world situation is a priority. Reports are being compiled of amphibian malformations--from extra pairs of legs to missing limbs and deformed eyes--including some occurring in Virginia localities. Only a long-term monitoring program will help determine if these are isolated, random mutations or a sudden, dramatic increase in genetic alteration.

Don't fill in the boggy area in your backyard. Watch it. Cherish it. Protect it. Record your observations in a diary. As Hamlet reminded Horatio, there are more things in heaven and earth than are dreamt of. And in those little boggy pools, there is more than meets the eye. pl

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