Through funding from the North Atlantic Landscape Conservation Cooperative (NALCC), The Nature Conservancy has completed the Lakes and Ponds Classification System, an addition to the Northeastern Aquatic Habitat Classification System (NAHCS). This mapped classification of lakes and ponds is based on variables that structure lacustrine natural communities and that can be mapped consistently across Northeastern United States.

The NAHCS has been an ongoing mapping project since 2008, when the Nature Conservancy and the Northeast Association of Fish and Wildlife Agencies (NEAFWA) completed a GIS dataset of natural aquatic habitat types in the northeastern states and a classification system to improve conservation of these habitats. The project received additional funding through the Northeast Regional Conservation Grants program to increase utility of the data by developing a user-friendly habitat guide to provide for each habitat a description, photograph, statistics and distribution pattern, crosswalks to state classification schemes, and wildlife associations for northeast fish and mussels. In 2012, the project also received funding from the NALCC to address two limitations of the classification system noted by users; tidal systems and lakes were not previously included in the classification system.

The Lakes and Ponds Classification System includes all waterbodies in the Northeast and Mid-Atlantic based on four key variables: alkalinity, trophic level, temperature, and depth. The integration of the four classification variables yields a flexible classification scheme that can be used in its full or simplified formats. Water temperature was classified into three classes (very cold, cold-cool, warm) to reflect the requirements and limits of aquatic organisms. Trophic levels, representing the productivity of a lake, were mapped into four classes (oligotrophic, mesotrophic, eutrophic, and hypereutrophic). Alkalinity was grouped into three classes (high, medium, low) to reflect how well the lake system was buffered from acidification. Depth was divided into two classes (lake, pond) based on a light penetration zone, using maximum depth and trophic level as a proxy for this zone. A steering committee of state and regional experts contributed sampled data with measured values of these and other variables for waterbodies in their states. Additionally, TNC received lake survey information from the National Lake Assessment and the New England Lake and Pond Survey.

The classification allows users to study the variation in the ecological character of lakes and ponds in the Northeast and Mid-Atlantic, and can help lead to improved conservation and management of these ecosystems. The results can be used to focus field surveys and assessments, or allocate management budgets to certain types of lakes and ponds. (mg)

The Wildlife Management Institute (WMI), in partnership with the U.S. Fish and Wildlife Service (FWS) is providing support to the Landscape Conservation Cooperative (LCC) network. This section of the Outdoor News Bulletin provides readers with regular updates on LCC efforts involving WMI.