By Shelley Harms

An egg mass is spotted in one of Norfolk’s many vernal pools.

Wood frogs began calling in early April, and a group of Norfolk volunteers were ready to begin the fourth year of mapping Norfolk’s vernal pools. The vernal pool mapping effort gets a boost when volunteers can literally follow the frogs’ calls to the pools. While it is possible to identify a vernal pool after the wood frogs finish their calling frenzy, it is much easier to find a vernal pool when the frogs are advertising their presence. An informal group of volunteers started the project in 2005, with the help of the Northwest Conservation District. The effort to map the vernal pools was then adopted in 2006 by the Natural Resources Inventory Subcommittee of the Norfolk Inland Wetlands Agency/Conservation Commission. The vernal pool map will be included in the Natural Resources Inventory the subcommittee hopes to publish by the end of this year. The town of Colebrook is undergoing a similar effort. Vernal pools are an unusual form of wetland. They have no fish and are used by wood frogs and several types of salamanders for breeding. Frequently, vernal pools dry up completely after several weeks and can only be found during the spring. As part of the mapping effort, volunteers are required to visit a vernal pool twice and fill out a data form for each visit. They must pinpoint the pool on a map and take photos of the pool and of evidence that “obligate species” (such as wood frogs or salamanders) are using it. Once the data packet is complete, it is provided to Alex Persons, a mapping expert, who gives the pool a unique identifier and puts it on the Norfolk vernal pool map. If a parcel of land is surveyed completely, but no vernal pools are found, Persons will highlight the parcel on the map to show that it is “done.” Two training sessions for volunteers were held this spring at Aton Forest, led by John Anderson. Volunteers learned how to identify wood frogs, spotted salamanders and their egg masses, and how to fill out the data forms. Sixteen vernal pools have been found and mapped at Aton Forest alone, and Anderson hopes to continue monitoring and studying the pools that are found elsewhere in town. At the end of the spring season in 2007, Norfolk volunteers had completed surveying 11 parcels and confirmed 62 vernal pools. Some of the parcels were quite large, such as Haystack and Dennis Hill State Parks and Aton Forest, but even so, less than one quarter of Norfolk has been covered. It is not expected that all of Norfolk can be surveyed by the end of this spring, so the map to be published in the Natural Resources Inventory will be a work in progress. To be a volunteer, or to give permission to have volunteers survey your property for vernal pools, contact John Anderson at johnanderson7440@sbcglobal.net or 542-5125.