How does a healthy ecosystem
protect Lake Champlain?
A healthy Lake Champlain ecosystem relies on clean water, but also requires intact, functional fish and wildlife habitat. Efforts to reduce habitat fragmentation and maintain habitat diversity include removing barriers to fish and wildlife passage, restoring and protecting wetlands, shorelines, and river banks, and preventing the introduction of aquatic invasive species. These efforts are also critically important in protecting water quality.
The Lake Champlain ecosystem contains all forms of life in and around the Lake, together with their habitats, which include the quality and temperature of the water and the local climate. The Lake’s biological diversity refers to the large number and variety of native species of plants, animals, and microorganisms, in a variety of habitats within the ecosystem. Over the course of many thousands of years, a complex, dynamic, and relatively stable web of life that relies on many habitat types has been established in the Lake (Figure 13).
Lake Champlain is experiencing environmental, biological, and chemical stresses that influence the ecosystem and are causing the character of the Lake to change. Seasonal temperature and precipitation patterns are changing toward warmer and wetter conditions. Changes in the landscape, especially from development and agriculture, negatively affect the Lake by altering water quality and the related food web, directly affecting the wildlife, fish, plants, and other organisms that live in the Lake and its watershed. Increasing concentrations of phosphorus and decreasing frequency of lake-wide winter ice exert additional stress on the Lake ecosystem and its native species.
Certain types of habitats that support the biodiversity of the Lake ecosystem are also critically important in protecting water quality in the Lake. Wetlands and riparian areas provide nursery habitat, water storage, nutrients, and food for fish and wildlife. They also protect water quality by temporarily storing flood waters, filtering sediments and nutrients, and buffering river banks during high flows. In Vermont, over 3,300 acres of wetlands have been conserved since 1991, thanks to a strong partnership between the US Fish and Wildlife Service, USDA Natural Resource Conservation Service, private land owners, and other organizations working toward this goal (Figure 14). These groups are working to restore as many as 85,000 acres of wetlands in Vermont.
Development, especially roads and culverts, can create barriers between aquatic animals and important parts of their habitat, especially during the breeding season. Vermont and New York now have guidelines for improving aquatic organism passage (AOP) when culvert or bridge work is underway. Fishery and other resource managers are working with municipalities to install culverts and bridges with a greater capacity to handle large volumes of flood water, which will reduce erosion and allow aquatic organisms to reach spawning areas. Identifying, mapping, and assessing culverts at the watershed level can help resource managers and watershed organizations determine which stream crossings are most in need of improved AOP.