Benefits of Beavers
Because beaver ponds create wetlands that are important habitat for many other mammals, birds, fish and amphibians, native Americans called this species the "sacred center" and scientists call them a keystone species. Wetlands are very important habitat for many endangered species.
Besides providing critical wetland habitat, Beaver dams slow the water's flow, which reduces erosion and decreases flood damage downstream. Water sinks into the ground, replenishes the water table, and increases riparian vegetation. And, very important here at Lake Tahoe, beaver dams also cleanse the water by filtering out silt, nutrients and other pollutants (that then biodegrade behind the dam) which prevents them from entering the Lake. A study done at Taylor Creek in South Lake Tahoe showed large increases in phosphorous entering Lake Tahoe when beaver dams were removed to enhance spawning of introduced Kokanee salmon.
Open areas created by beaver ponds in forests provide a mosaic of more diverse and complex habitats that benefit many species. Trees flooded and dead provide important cavity nesting sites for many birds and other species. When beavers chew fast growing trees and shrubs like aspen and willow, it encourages even bushier re-growth the next spring, which provides better nesting habitat for songbirds.
Beavers and their dams and ponds can help mitigate the impacts of climate change. Diminishing snowpacks and warmer temperatures cause streams to dry up earlier.
Water held in beaver dams upstream provides water later and throughout the summer season.
Best of all, beavers do all this work for free, and they don't need permits! Nobody is better at building and then maintaining wetlands than beavers.
Fish especially benefit from beaver ponds. Many scientific studies show beaver ponds are rich in insects and invertebrates for food, and fish in ponds are larger and more abundant. Beaver ponds provide important refuges for young fish from predators and from strong currents or spring run-off in larger streams and rivers.
Contrary to popular myths among fishermen, the deeper water in beaver ponds is cooler than shallower streams, and entirely beneficial for cold-water fish such as trout and salmon. The range of water temperatures, from warmer at the top to cooler at the bottom, provides good habitat for a much greater variety of invertebrates for food. When water slows and sinks into the ground behind beaver ponds, it is cooled and seeps back into creeks, actually cooling the water downstream. Since beaver dams also filter sediments out of the water, they create more clean, gravel stretches that fish need for spawning below the dams.