FISH AND WILDLIFE HABITAT

Beaver dams and ponds:

• provide fish protection from strong winter flows,

• increase storage of water resulting in a more stable water supply and maintenance of higher flows downstream for a longer period of time,

• provide plenty of woody debris where juvenile fish can hide from predators,

• provide pool habitat that is important for fish such as cutthroat trout and coho salmon,

• store leaf litter and woody debris in the water, which supports aquatic insect production, an important food source for fish, amphibians, waterfowl, bats, and songbirds,

• provide and improve nesting and brood rearing areas for waterfowl,

• attract and provide habitat for river otters, muskrats, turtles, frogs, and salamanders; and

• stimulate riparian vegetation growth which provides additional forage and cover for a variety of wildlife.

Sometimes trees will die as a result of rising water levels behind beaver dams. However, these dead trees quickly become part of the stream ecosystem and attract insects that are a food source for many wildlife species such as woodpeckers. They also provide homes for cavity-nesting birds and bats.

Trees felled by beaver provide locations for bird roosting and nesting, turtle basking, and cover for fish and small mammals.

Riparian and wetland communities thrive with beaver activity, increasing in size and habitat diversity to support a greater number of species.

WATER QUANTITY AND QUALITY

Beaver dams create wetlands which help control downstream erosive flows and flooding by storing and slowly releasing water over time. This has multiple positive impacts on water quantity and water quality, for example:

• Beaver dams, ponds, and wetlands improve water quality by removing or transforming excess nutrients, trapping silt, binding and removing toxic chemicals, and filtering out sediment.

• Beaver dams facilitate ground water recharge and help raise the ground water table. The elevated water table helps maintain a more constant and elevated stream baseflow throughout the drier periods of the year and promotes vegetative growth, which in turn helps stabilize stream banks and minimize erosion.

• Beaver dams reduce water velocity, which reduces channel scouring and streambank erosion downstream of the dam.

CLIMATE RESILIENCE

Wetlands and riparian areas influenced by beaver activity are often more resistant to wildfire and drought because the beaver activity slows down streamflow, raising the water table, spreading out surface water across the floodplain, so that it irrigates the valley floors and keeps plants green and thriving even in a drought. The healthy green vegetation and saturated soils around beaver ponds and wetlands slow down the spread of wildfires and provide refuge for animals to escape the flames.