Beaver Library

Beavers modify landscape morphology and hydrology, thereby creating habitat for
diverse species, enabling many ecological processes, and promoting climate change resiliency.
Beavers are now rebounding from near extirpation in North America and increasing beaver
populations can facilitate restoration goals given beavers’ roles as ecosystem engineers. This is
especially relevant in the Chehalis Basin in western Washington where beaver is a focal species in
the Aquatic Species Restoration Plan (ASRP) which aims to protect and restore critical aquatic
habitat. Although beaver can be valuable for restoration, they can also cause conflict with people by
damaging trees, flooding roads, etc. Given potential conflict and the role of beaver in restoration, we
surveyed landowner perceptions of beaver and collated data on the status of beaver in the Basin.
Our landowner survey provides information to begin assessing the Chehalis Basin community’s
understanding of and desires for beaver. Our study explicitly explored whether negative attitudes
towards beaver are positively correleated with an individual’s reported conflict with beaver.
Notably, we found that landowners experiencing conflict with beaver were more likley to agree
with lethal control of beaver and disagree with maintaining beaver-created habitat than
landowners not experiencing conflict. This survey’s results underscores how proactively
addressing human-beaver conflict in the Basin is crucial for avoiding increasing negative attitudes
towards beaver and beaver-related restoration. Our survey supports a need for outreach and
education on beaver conflict mitigation, particularly related to unwanted tree removal. We also
present trends data on recreational beaver trapping in the region and areas of reported beaver
conflict. Although robust beaver population data are lacking, we provide a compilation of known
beaver occurrences as a baseline for beaver activity, especially near restoration priorities. These
beaver status data, in conjunction with our landowner survey data, provide a comprehensive
picture of the state of beaver, beaver conflict, and beaver restoration in the Chehalis Basin. Our
findings can help guide restoration practitioners in the Chehalis Basin to best capitalize on beaver’s
habitat restoration potential while mitigating conflict now and into the future.

Understanding where and how many dams beavers (Castor canadensis) will build is an important habitat restoration question, especially as beavers are increasingly recognized for their ecosystem-scale benefits and as beaver-related restoration accelerates. Several models exist for predicting the dam building behavior of beavers in North America. However, not all of these models are applicable outside of the ecoregions where they were developed or validated.

A decision support and planning tool for beaver management, to analyze all perennial rivers and streams in Utah. This model assess the upper limits of riverscapes to support beaver dam-building activities.

Late 1800s – 1900s beaver studies which cover a period of twenty-seven years through every State in the Union, Mexico, Canada, and Alaska.

Traditional restoration efforts are barely scratching the surface of what could be restored. Moreover, a disproportionate amount of funds are spent on too few miles of streams and rivers leaving millions of miles of degraded streams neglected. To fill this gap, restoration practitioners are increasingly trying restoration techniques that are more cost?effective, less intensive, and can more practically scale up to the enormous scope of degradation.

Report on capture success of beavers in box traps, box trap designs and modifications, field sets, and costs of purchasing and modifying traps.

Investigation into the social dimensions of wildlife reintroduction and an argument to emphasize the need to recognize societal perceptions in potential management solutions

This article looked at castor canadensis in Chile and Argentina in the 1990s. Data found that beaver eradication strategies and ecosystem restoration efforts should focus on the ecology of native ecosystems rather than the biology of beaver.

A study of beaver control measures to help land management agencies weigh against large-scale removal programs

Beaver relocation program by the Wyoming Game and Fish Department.

Relocating American beavers (Castor canadensis) from unwanted sites to desirable sites where damage exceeds stakeholder capacity) has been posited as a method to enhance in-stream habitat for salmonids in the Pacific Northwest.

Washington’s Cowlitz Indian Tribe’s ambitious project: to reintroduce beavers back into the Gifford Pinchot national forest, a wild region on the slopes of the Cascade mountains, as part of efforts to reclaim indigenous land management practices.

A review that investigates the mechanisms by which beavers act as ecosystem engineers, and then discusses the possible impacts of beavers on the biodiversity of Scotland.

Study that examines relationships between dam density, riparian area characteristics, and the riparian bird community in a semiarid landscape.

Survey that identifies a need to assess beaver-related restoration projects in western rangelands to increase
awareness, accountability, and to identify gaps in scientific knowledge.

Article that finds themes in responses to beaver reintroduction and offers observations that may positively influence future responses amongst affected individuals

This guidebook provides a practical synthesis of the best available science for using beaver to improve ecosystem functions. The overall goal is to provide an accessible, useful resource for those involved in using beaver to restore streams, floodplains, wetlands, and riparian ecosystems.