Beavers

Learn why beaver populations were decimated and why their restoration is vital to ecosystem health on which humans and wildlife depend. Once widespread, the Eurasian beaver population was reduced to twelve hundred animals at the start of the twentieth century. In North America, between 100 and 400 million beavers existed prior to European colonization and could be found in nearly every watershed. Today, only 10 to 15 million beavers remain. Beavers were hunted for their water-resistant fur, used for hats and clothing, and their castoreum, used in medicine and perfume. Their dams and ponds were eliminated to create farmland. As ecosystem engineers, beavers build dams in almost any place where water can be impounded, wood is available, and habitat can be improved (from their perspective). Ponds protect beaver lodges from predators. Some landowners object to beavers, incorrectly thinking the dams interfere with water supplies. Some consider beavers a nuisance for blocking waterways and culverts and for cutting down trees. Despite viable alternatives, trapping or killing is often the only remedy employed, eliminating the ecological benefits that beavers provide. These benefits include:

• Beavers are one of the few mammals on the planet that actively modifies their habitat and can therefore be employed to restore streams, wetlands, and floodplains and repair eroded ecosystems (see next section).
• Beavers are one of twenty mammal species on the planet whose reintroduction could have positive, cascading effects on biodiversity.
• Beaver dams slow snowmelt, extending stream flow in the summer and recharging groundwater, which is critical for drought management.
• Dams slow flood events, which otherwise could cut stream channels downward, causing erosion and depositing sediment downstream.
• Dams create wetlands, one of the most important types of ecosystems on the planet (see Wetlands Nexus).
• By slowing and trapping sediments transported by water, up to two feet of sediment per year can be caught behind beaver dams. This sediment sequesters atmospheric carbon and improves water quality by filtering out pollutants, such as fertilizer originating from farm fields upstream.
• In England, research demonstrated that a single family of beavers built thirteen dams over ten years, creating a series of deep pools that removed high levels of nitrogen and phosphorus from the stream.
• Beaver dams can be very large, and some sites are occupied for as long as fifty years.
• Removing trees allows sunlight to reach the water, triggering a cascade of biological activity. Algae and water-loving plants grow in the sunlight. The nutrient-rich water feeds microscopic organisms, which then feed a variety of insects, which become food for fish, birds, and eventually mammals.
• An entire food chain is created in a single beaver pond.
• Ponds created by beaver dams change plant communities from dryland to wetland species. They allow sedges and other deep-rooted plants to grow, which stabilize banks and provide shade, reducing water temperatures and providing long-term ecological resilience.
• Ponds raise water tables, sub-irrigating nearby land, including farmland, as well as land downstream, according to research in Colorado.
• Ponds are nurseries for salmon and trout.
• Ponds are magnets for wildlife, including deer, muskrats, mink, otters, toads, frogs, and water-loving birds, such as ducks.
• The killing or removal of beavers from watersheds can have negative cascading effects, including damage to fish, animal, and bird populations, a decline in water quality, and an increase in the size and frequency of flood events that can affect farms and cities downstream. Degraded land can damage ecosystem services, the essential services that nature provides, such as nutritious food, clean water, pollution removal, and carbon sequestration (see Degraded Land Restoration Nexus).
• Beaver populations can be adversely affected by industrialized activities, including deforestation, the use of agricultural chemicals, conventional agriculture, land clearing, and mining. They can benefit from regenerative alternatives (see Regenerative Agriculture Nexus, Agroecology Nexus, and Agroforestry Nexus).

Join an organization, support a campaign, and/or participate in an activity that protects or restores beaver populations and their habitat. Although regulation and management of beavers is usually controlled by wildlife agencies within federal, state, and local governments (see Governance), there are many organizations that work on behalf of beavers and their habitat. Work includes research, advocacy, surveys, beaver relocation projects, education, and other volunteer, community-based initiatives (see Key Players). Eurasian beaver populations have recovered dramatically as a result of reintroduction efforts by many people and are now estimated to number more than one million animals.

• A major beaver restoration effort is underway in the UK. Last sighted in 1789, beavers began to be reintroduced in the 2010s. Licensed sites include former habitats in England, Wales, and Scotland, where the beaver population has doubled to 1000 animals in three years and can be found in 250 separate locations. The benefits are multiple and documented. The effort has required overcoming legal challenges and opposition from farmers and anglers. Farmers have a legal right to eliminate nuisance beavers from their land, which puts them in conflict with conservationists.
• In 2020, the UK government determined that an experimental population of beavers in Devon could stay, citing the significant ecological benefits they provided. The project is managed by the nonprofit Devon Wildlife Trust, which offers educational and volunteer activities. Public support for the reintroduction project has been important to its success. Here is a list of beaver restoration projects in the UK. The Wildlife Trusts operate many programs for volunteers in the UK.
• The Beaver Institute has a two-part online BeaverCorps Training Program focused on wetlands and nonlethal conflict resolution.
• The Lands Council in Washington State has volunteer activities for people interested in beavers. Other projects in Washington include the Methow Beaver Project and the Yakima Beaver Project.
• The National Wildlife Federation publishes a guide on how to advocate for beaver restoration in U.S. national forests.
• Find a local Beaver Working Group, such as this one in Montana and this one in Colorado.
• Beavers are being restored in arid environments, including river systems in Utah. Here is a story from Colorado.
• The Occidental Arts & Ecology Center in California has a long-running  Bring Back the Beaver campaign.
• The beaver is a national symbol of Canada (depicted on the 5-cent coin) and the nickname of the State of Oregon.
• Groups such as The Fur Bearers work to protect the species there. Here is their list of beaver management literature.
• Indigenous tribes are involved in beaver restoration projects. On the Blackfoot Reservation in Montana, the Ksik Stakii (Beaver) Project is repairing degraded waterways and recharging underground aquifers. The Tulalip tribe in Washington is employing beavers to boost declining salmon numbers in rivers.
• Celebrate International Beaver Day (April 7) by taking a hike with friends to a beaver pond or arranging a public display on beavers.
• Wild beaver tourism is becoming a popular activity as well as a way to fund restoration projects.

Speak up. Write an op-ed to a newspaper or social media site advocating for beavers, particularly the need to protect and restore their habitat. Destructive human activity needs to be highlighted. Here is an op-ed from Oregon protesting federal policy that allows beaver killing. Here is an op-ed in The New York Times linking beavers to the reintroduction of the gray wolf as an example of the role keystone species play in restoring ecosystem health. Here is an op-ed from the UK advocating for the reintroduction of beavers.

• The Beaver Institute provides an extensive library of articles, videos, and web links that can help with research and writing.

Join a social media site run by an advocate for beavers. Here is a sampling of social media sites (see Key Players below):

• The Beaver Institute on Facebook.
• Worth a Dam has an active blog.
• Beaver Trust on X.
• Beaver Management Forum on Facebook.
• The Fur Bearers on Facebook.
• Welsh Beaver Project on X.

Learn why beavers can be beneficial to your land and explore ways to coexist with them. Conflicts with beavers are real and have consequences. Their dams can flood crop fields, roads, and irrigation canals. Beavers cut down trees and damage human-made landscaping. However, removing beavers is not very effective since they will likely be replaced by new beavers. Conflicts can be mitigated. Landowners are learning that the benefits of beavers are significant. Dams keep water on the land longer, which is useful in a drought. Beavers are wetland carbon engineers, useful in an era of climate change when there is greater variability in weather extremes. Beavers increase the land’s ecological resilience to unanticipated changes. Strategies and resources to mitigate the negative impact of beavers include:

• Wait for them to leave. Beavers will eventually eat all the food available to them and move on. As a bonus, the land will become unattractive to other beavers in the area.
• Remove small trees and woody vegetation that beavers like to eat, which will reduce their food supply and encourage them to leave.
• Protect trees from beavers with cylindrical wire fencing. Painting trees with a mixture of sand and latex paint will discourage beavers.
• Install fences and barriers around culverts, drains, and structures to keep beavers away.
• Employ electric fencing to discourage beavers from staying in an area.
• Install a pond leveler, which is a flow device that holds the water level at a set height. Most types of pond levelers hide the drain in the middle of the beaver pond, where beaver don’t look for it. Here is a case study from southern England.
• Nonlethal guides and resources for landowners can be found from the USDA and Animal Protection New Mexico.
• Minimize the sound of running water. Lowering the water table of a beaver pond or piercing the dam can create the sound of moving water, which is a signal to beavers to make repairs.
• Install a Beaver Deceiver (see City and County Land Managers below).

Work with agencies and others to restore beaver populations if you own appropriate habitat. Research demonstrates that beavers can help achieve restoration project success.

• Start a pond with a Beaver Dam Analogue (BDA), often a series of vertical posts placed in a stream, interwoven with branches, and packed with mud. The pooled water entices beavers to move in, build lodges, and increase the size of the dam. Here is an example from a ranch in California.
• Consult with a beaver expert. There are private companies, such as Ecotone, and individuals, such as Skip Lisle, that provide a variety of beaver coexistence services. Many state game and wildlife departments have beaver experts or can point you toward one.
• Consider the tourism potential of having beavers on your land. Many countries in Europe have now reintroduced beavers, driven in part by the affection that people feel for the rodent. In the Knapdale area of Scotland, one local hotelier has reported that 20 percent of his guests were there because of the reintroduced beavers.
• The Beaver Restoration Guidebook, produced by the U.S. Fish & Wildlife Service and three other federal agencies, provides a practical, science-based approach for using beavers to improve ecosystem functions.
• Join a collaborative restoration effort or a watershed group. There are regional, multistakeholder groups in the U.S. and UK involved in restoration activities and environmental conflict resolution that could help beavers. Groups include the Western Landowners Alliance, Sustainable Northwest, the Quivira Coalition, and the Working Lands for Wildlife. There are localized groups, including the Salmon Falls watershed collaborative in New Hampshire and the Blackfoot Challenge in Montana.

Stop the loss of beaver habitat in cities and on county, state, and federal land, and restore beaver populations. Many of the challenges and conflicts involving beavers fall under government agencies' jurisdiction. One example is the maintenance and protection of public roads, which are deteriorating as a result of more frequent and intense storm events resulting from climate change. The presence of beavers can complicate things. They can challenge flood management options as well. New thinking and investment in infrastructure are required. Options include:

• Replace small culverts with larger and wider ones that would allow debris from bigger storm events to pass through and be less attractive to beavers.
• Install a Beaver Deceiver, a nonlethal flow device that prevents culverts and other structures from becoming dam sites for beavers. Here is a Beaver Deceiver lecture by its inventor, Skip Lisle. Here is an example from Vancouver, B.C., involving the airport.
• Consider the positive role beaver dams and ponds can play in aquifer recharge and incorporate them into land-use planning.
• Beaver Solutions offers Beaver Management Plans and consulting for towns, agencies, and utilities.
• The Beaver Restoration Assessment Tool (BRAT) is a regional planning tool to assess the potential of beavers as ecological restoration agents.
• The Fur Bearers, a Canadian nonprofit, publishes numerous options in Beavers: Coexistence Strategies for Municipalities and Landowners.
• The Beaver Institute has started a biennial conference called BeaverCon that brings together restoration professionals, engineers, ecologists, land managers, and infrastructure specialists to learn what works.

Expand research on beavers. Areas of investigation include resolving conflicts over beaver reintroduction efforts, understanding public perceptions, exploring new roles for beaver restoration, and developing long-term management strategies:

• Understanding the social dimensions of beaver reintroduction is critical to developing effective management strategies that gain public support and reduce conflicts.
• There are few studies focused on what happens to beavers after they are translocated to a new area, making it difficult to determine best practices. This study focused on beaver relocations in the Coast Range of Oregon.
• The effects of beaver activity in landscapes that are sensitive to climate change need to be expanded. NOAA has a research article about the impacts new beaver dams are having on the tundra ecosystem of the Arctic as temperatures warm.
• More research is needed to understand the role beaver dams and ponds can play in the removal of agricultural chemicals and other pollutants from streams and lakes.
• What role can beavers play in urban and suburban areas? Georgia State University and Saporta Report have articles focused on the positive role beavers can have in urban stormwater management.

Support enterprises that protect, maintain, and restore beaver populations, particularly those involved in agriculture. Companies should support organic products and regenerative agricultural practices that improve soil health, protect ecosystems, and reverse land degradation (see Degraded Land Restoration Nexus and Regenerative Agriculture Nexus).

The Beaver Believers Documentary by Tensegrity Productions (63 mins.)

Why Do Beavers Build Dams? Nature's Engineers (Wildlife Documentary) | Natural Kingdom by Canadian Geographic (46 mins.)

Beaver Lodge Construction Squad | Attenborough by BBC Earth (10 mins.)

The Beavers are back - Busy river monsters at work by 
Free High-Quality Documentaries (50 mins.)

Beavers Without Borders: a short documentary by The Beaver Trust (16 mins.)

Dam It: Why Beavers Matter by Ben Goldfarb (31 mins.)

Why BEAVERS Are the Smartest Things in Fur Pants by Be Smart (5 mins.)

How Beavers Build a Dam Longer Than Hoover Dam by BioArk (7 mins.)

Releasing Beavers to Heal Degraded Western Streams by Sageland Collaborative (5 mins.)

Beaver: Back to the Future by The Grand Canyon Trust (13 mins.)

Beavers and Salmon by psmfcvideo (7 mins.)

Creating Miracles in the Desert: Restoring Dixie Creek by Intermountain West Joint Venture (10 mins.)

Living with Beavers by The Cornwall Wildlife Trust (14 mins.)

Beavers in Our Landscapes: Ecology and Case Studies by Cows and Fish (57 mins.)

Understanding Beavers as a Natural Infrastructure Solution by The Miistakis Institute (59 mins.)

Coexisting with Beavers Part One (12 mins), Part Two (18 mins.) by The Miistakis Institute

The Return of California’s Golden Beaver by Guadalupe-Coyote Resource Conservation District (7 mins.)

Partnering with Beaver to Restore Colorado Mountain Riverscapes by Mark Beardsley (34 mins.)

Beaver Exclusion Fencing Installation - Training Session by The Miistakis Institute (7 mins.)

Beavers and Stormwater by Clark CD (74 mins.)

12 Videos Featuring Skip Lisle by The Beaver Deceivers (3-124 mins. each)

Eager: The Surprising, Secret Life of Beavers and Why They Matter by Ben Goldfarb

Once They Were Hats: In Search of the Mighty Beaver by Frances Backhouse

Bringing Back the Beaver: The Story of One Man’s Quest to Rewild Britain’s Waterways by Derek Gow

Saving the Dammed: Why We Need Beaver-Modified Ecosystems by Ellen Wohl / Oxford University Press

Lily Pond: Four Years with a Family of Beavers by Hope Ryden / William Morrow & Co

The Beaver: Natural History of a Wetlands Engineer by Dietland Muller-Schwarze / Comstock Publishing Associates

Dam Builders: The Natural History of Beavers and Their Ponds by Michael Runtz / Fitzhenry and Whiteside

The Eurasian Beaver Handbook: Ecology and Management of Castor Fiber by Campbell-Palmer et al. / Pelagic Publishing

River Otter Beaver Trial: Science and Evidence Report (UK), a report of the five-year reintroduction of Eurasian beavers in Devon

Beaver and Climate Change Adaptation in North America: A Simple, Cost-Effective Strategy by WildEarth Guardians et.al

The Beaver Restoration Guidebook: Working with Beavers to Restore Streams, Wetlands, and Floodplains by the U.S. Fish & Wildlife Service

A Conversation with Author Ben Goldfarb by National Wildlife Federation (30 mins.)

Become a Beaver Believer by Defender Radio (31 mins.)