Longest beaver dam in world, Wood Buffalo National Park, Canada
The fur trade began in Washington State in the 1700s when initially English ships soon followed by Russians, Spanish, and later Americans collected sea otter pelts along the coast for trade with China. Inland fur trading that had begun to the east progressed westward via river routes reaching what is now Washington State in the early 1800s. Fur trading posts established near the coast connected with the river routes and the river trade network. This era of fur trading had profound effects on the economics of the area and ultimately shaped the history and landscape of what is now called Washington State.
The rate of taking of furs was never remotely sustainable. For example the sea otter was nearly driven to extinction. Inland fur bearing animals did not fair much better. The Hudson Bay Company which ultimately developed as the dominant company may have developed some sense that fur trapping needed to be done in a manner that would not trap out the resource. However, with American encroachment and concerns that furs were attracting Americans, the Hudson Bay Company began an aggressive trapping approach to clear out furs that were attracting American interest in the hope of stemming the tide of American settlement in the Pacific Northwest.
The result was vast riparian areas devoid of beavers. As a consequence, the stream processes we observe today may not correlate well with the geomorphic features observed. I remind myself that beavers might once have been present in a stream system I am working on. And in trying to project into the future it is important that the possibility of future beaver activity could result in much different stream behavior than that currently observed.
Part of living in the Anthropocene is recognizing that human impacts on the geomorphic processes are not always by direct action. In addition, we need to recognize we are not the only species that impacts geomorphic processes.