In this way, the beavers change the forest's compostion. Eventually, the beavers eat themselves out of house and home. They then turn to their last resort, pine trees and other conifers. Having finally exhausted their food supply, the beavers then leave for new territories. Although the girdled trees die, the forest can actually benefit.
More sunlight can reach the forest floor, allowing sun-loving species to grow.
Living trees have more room to grow and expand, and the standing dead trees provide good nesting holes for woodpeckers, owls, squirrels, raccoons, and other forest birds and mammals. Eskers are glacial formations, created as sediments were deposited along the course of a stream tunneling beneath a melting glacier. Most of the finer sediments scraped from the land, such as clay, silt and fine sand, were swept away in the swift current, but coarser sand and gravel eventually filled the stream's tunnel. When the ice finally melted away several thousand years ago, the tunnel of sediment emerged as a 10-100 foot high ridge, resembling a railroad embankment. As you travel through these woods, notice how the esker creates a microenvironment on either side of it.