Last modified: Monday, February 25, 2008 6:01 PM EST Vernal pools are easily seen when covered in ice in the winter, but by mid-summer they're typically bone dry. (Photo courtesy of Vernal Pool Association) 'Big Night' part of vernal pool initiative BY SUSAN LaHOUD / SUN CHRONICLE STAFF NORTON -- It will be a "Big Night" for certain critters soon. Big Night occurs during a relatively warm and rainy night between March 8 and April 15 when, in an ancient migration ritual, frogs, salamanders and other creatures crawl, hop and fly up to a mile to hit the pool - a vernal pool, that is. Now in the second year of its Vernal Pool Project, the Manomet Center for Conservation Sciences is working to ensure that these unique water bodies are preserved because they are critical to species' breeding as well as an indicator of water quality affecting human health. The 40-year-old nonprofit conservation organization, based in Plymouth, last year visited and took water samples from 89 vernal pools in the Taunton and Charles River watersheds. The two areas were chosen because of their proximity to the center, the diverse land uses in those areas, and the fact they have active watershed associations, said the center's Beth Brazil. Of the 70 participating communities, Norton had the most certified vernal pools, she said. The center's project relies on partnerships with other organizations, local conservation commissions and land trusts as well as private individuals who allow water samples to be taken and provide related information. "We want to bring people to the table," Brazil said. The focus of the project is the effect that surrounding land uses, such as road salting, have on water quality in vernal pools. Brazil, who recently spoke about the project at the Norton Public Library, said a report is expected to be out this month. The second step of the research will include revisiting those vernal pools and might go further by studying the sediment in them, since creatures like fairy shrimp, a crustacean, bury themselves in it as opposed to leaving the pond. At this point, the center is not looking for more vernal pools but encourages people who believe they may have one on their property to seek formal certification. That process includes taking pictures of the pool over time and documenting species in it. The Mass. Audubon Society is among the resources people can tap to find out details for certification. Vernal pools are essentially temporary wetlands, with no inlet or outlet. They typically do not hold water permanently and contain no fish. There are more than 3,000 certified vernal pools in Massachusetts and potentially 30,000 more that have not been documanted, according to Geographic Information Services. Species that are completely dependent upon vernal pools at some point in their lifespans, and were spotted in pools visited by individuals from the center, include fairy shrimp, wood frogs and spotted salamanders. Species that use both vernal pools and other wetland habitats for various activities include the spring peeper, green frog and spotted turtle, Brazil said. While there is a lot of literature about vernal pools, the project was launched because more research is needed on hydrological processes, threats to amphibians, land use and contaminants, she said. There is no threat of legal liability to property owners involved in the project; if contaminants are found, it is a matter of offering suggestions to either eliminate or reduce them. Pesticides, lawn care chemicals and all-terrain vehicles are among the threats to vernal pools. Preserving a buffer around them is critical because of wildlife that rely on them for a part of their life cycle. Brazil said Massachusetts has actually been a leader in protecting vernal pools with regulations in place for about a decade. Vermont has just started putting regulations on the book. Here are some resources on vernal pools, including how to go about getting one certified. People can also contact conservation offices or commissions in their community about certification: “A Field Guide to the Animals of Vernal Pools” by Leo P. Kenney and Matthew R. Burne, Natural Heritage & Endangered Species Program, Massachusetts Department of Fisheries and Wildlife, is available from www.mass.gov/dfwele/dfw/nhesp/publications. “Certified: A Citizen’s Step-by-Step Guide to Protecting Vernal Pools,” 5th edition, Elizabeth Colburn (editor), is available from www.massaudubon.org/shop. Vernal Pool Association: www.vernalpool.org. SUSAN LaHOUD can be reached at 508-236-0398 or at slahoud@thesunchronicle.com.