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Beavers As Climate Change Fighters | Earth Wise

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California is fighting the effects of climate change on multiple fronts.  The state has been grappling with relentless drought, record heat waves, and persistent wildfires.  The California Department of Fish and Wildlife is enlisting the help of beavers in its battle against climate change.

The state has created a beaver restoration unit charged with developing methods for nature-based restoration solutions involving beavers as well as artificial beaver dams. The agency plans to spend at least $3 million over the next two years to oversee a restoration program for the North American beaver.

A 2020 study showed that beaver-dammed corridors were relatively unharmed by wildfires compared with other areas that lacked beaver damming.  The study highlighted the differences between two adjacent corridors – one without a beaver population with a landscape scarred by a recent wildfire and another with beavers that remained a lush wetland after a fire.   The differences in burn severity, air temperature, humidity, and soil moisture between the beaver complex and the adjacent landscape were huge. 

From the 1920s through the 1950s, California actively exported beavers to other parts of the state and country so they could build dams in eroded areas where beaver dams could help evenly distribute water.  Now, the state wants to reintroduce beavers into watersheds where they once flourished.

The Department of Fish and Wildlife’s proposal to the California Legislature called beavers an important keystone species that can be used to combat climate change.   The state has spent enormous amounts of money on wildfire measures with minimal results.  Now they are going to see if beavers can make a difference.

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California says the beaver can be superhero in fighting climate change

Photo, posted September 19, 2021, courtesy of Larry Lamsa via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Rewilding The American West | Earth Wise

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Oregon State University scientists have proposed a series of management changes for western federal lands aimed at re-establishing ecosystems there.  Their proposal would result in more gray wolves and beavers in nearly 200,000 square miles of federal lands in 11 states.

In each of those states, the researchers identified areas containing prime wolf habitat.  Gray wolves were hunted to near extinction in the West but have been gradually reintroduced in some areas starting in the 1990s.  Wolf restoration offers significant ecological benefits by helping to naturally control the population of grazing animals such as elk.  This in turn facilitates the regrowth of vegetation species such as aspen, which ultimately supports diverse plant and animal communities.

Beaver populations, which used to be robust across the West, declined roughly 90% after settler colonialism and are now nonexistent in many areas.  By felling trees and shrubs and constructing dams, beavers enrich fish habitat, increase water and settlement retention, maintain water flows during droughts, and increase carbon sequestration.

According to the researchers, the biggest threat to these western lands is livestock grazing, which has degraded ecosystems to a great extent.  They recommend the removal of grazing on about 30% of the federal lands being used for that purpose and instead would have rewilding efforts go on. 

The American West is going through a period of converging crises including extended drought and water scarcity, extreme heat waves, massive fires, and loss of biodiversity.  Rewilding is a way to reestablish long-standing ecosystems.

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More wolves, beavers needed as part of improving western United States habitats, scientists say

Photo, posted October 1, 2020, courtesy of Tina DaPuglet via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Beavers Are Flooding The Warming Arctic | Earth Wise

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The accelerating warming in the Arctic has transformed the region into a warmer, wetter, and more diverse environment.  Warming temperatures have encouraged the increasing growth of vegetation, particularly shrubs that provide beavers with bark to eat and branches to build with.  Warming temperatures also mean that lakes and streams freeze solid for shorter periods of time or not at all, allowing beavers to pursue their construction projects for longer periods during the year.

Prior to the mid-1970s, residents of the Alaskan Arctic encountered few beaver ponds.  In 2018, researchers using satellite imagery mapped 12,000 beaver ponds in Alaskan tundra.

Beavers are causing major changes in the streams and floodplains that many small Alaskan villages depend upon for food, water, and navigation.  As the rodents transform lowland tundra ecosystems, they are eliminating food sources, deteriorating water quality, and making it difficult to navigate waterways.

The migration of beavers across the Arctic landscape is largely a result of climate change.  But it is also becoming one of the factors amplifying climate change.  Scientists are trying to figure out the degree of permafrost thawing that beaver dam-and-den building is causing and how fast these defrosted organic soils will degrade and release trapped carbon and methane.

Beaver dams alter the hydrology of streams by slowing the flow, storing and spreading water to create wetlands, raising the water table, and lowering the oxygen content of the water. 

Climate-driven changes in species distributions affect human well-being as entire ecosystems continue to change.  Shifts in animal habitat stimulated by climate change could have profound consequences across the globe.

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Beavers Are Flooding the Warming Alaskan Arctic, Threatening Fish, Water and Indigenous Traditions

Photo, posted June 12, 2018, courtesy of Peter Pearsall/USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Beavers And The Warming Arctic | Earth Wise

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Beavers have a remarkable ability to transform landscapes.  Using their sharp teeth, they fell trees and shrubs and build dams, which cause small valleys to fill with water and form new lakes.  Some of these lakes measure five or ten acres in size, or even more.  And beavers are very efficient builders; they often build their dams at precisely those points where can they have the greatest effect with the least effort.

Scientists studying beaver activity in the Arctic regions of Alaska have found that the changing climate is leading to a substantial increase in beaver populations and their effect on the landscape.

In 2018, researchers found that the beavers living in a 7,000 square-mile area in northwest Alaska had created 56 new lakes in just five years.  Thanks to rising temperatures, more and more habitats offer the shrubs that beavers need for food and building material.  In addition, the lakes, which used to freeze solid, now offer beaver-friendlier conditions.  Also, beavers are not hunted as intensively as in the past.

The scientists were surprised that beavers have seized the opportunity so intensively.  There is basically an exponential growth in beaver dams.  This is actually a worrisome situation.  Forming all these new lakes degrades ice-rich permafrost in the area.  In the Kotzebue region of Alaska, the overall water area has increased by more than 8% over the past 17 years, and roughly two-thirds of that is due to beavers.

The degradation of the Arctic’s permafrost is a dangerous situation and it appears that anyone who wants to predict its future has to keep the activity of beavers in mind.

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Beavers gnawing away at the permafrost

Photo, posted June 23, 2018, courtesy of Becky Matsubara via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Beavers And Biodiversity

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Beavers are large, semi-aquatic rodents known best for their ability to construct dams, canals, and lodges (their homes).  They are among the largest rodents in the world.  With powerful jaws and strong teeth, beavers fell trees to use as building materials, often changing their environment in ways few other animals can. But in a good way.  As it turns out, beavers are important for biodiversity. 

According to new research from the Faculty of Natural Sciences at the University of Stirling in Scotland, reintroducing beavers to their native habitats is an important step towards solving the freshwater biodiversity crisis. 

Researchers surveyed water plants and beetles in 20 wetlands in Sweden – 10 created by beavers and 10 that were not – in order to understand what impact beavers might have on the variety of plant and animal life around them. 

The research team’s findings build on previous work that has shown that beavers have an important impact on biodiversity.  This latest study discovered that the number of species found only in beaver-built ponds was 50% higher than in other non beaver-built wetlands in the same region. 

Beavers are known to be profound engineers of the environment. They use wood to build dams across rivers in order to form ponds behind them.  They do this to raise the water level in order to avoid predators, like bears and wolves. But it turns out many other plants and animals, like water plants and beetles, also benefit from their work.

According to the research team, reintroducing beavers to their native habitats should benefit the wider biodiversity and be seen as an important step towards solving the freshwater biodiversity crisis. 

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Beaver reintroduction key to solving freshwater biodiversity crisis

Photo, posted October 2, 2014, courtesy of USFWS Midwest Region via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Decline Of Earth’s Largest Freshwater Creatures

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While nearly 70% of the globe is covered by water, only 2.5% of it is freshwater.  The rest is saline and ocean-based.  And only 1% of our freshwater is easily accessible, with much of it locked away in snowfields and glaciers.  

Despite freshwater only making up a small fraction of all water on the planet, it’s home to one third of all vertebrate species.  Some have survived hundreds of millions of years, but many of the world’s largest freshwater creatures – including fish, reptiles, amphibians, and mammals – may soon find themselves on the brink of extinction.

According to a study recently published in the journal Global Change Biology, scientists from the Leibniz-Institute of Freshwater Ecology and Inland Fisheries and international colleagues have quantified the global decline of freshwater megafauna for the first time.  In four decades since 1970, the global populations of these freshwater giants have declined 88% – twice as much as the loss of vertebrate populations on land or in the oceans. 

Freshwater megafauna include all freshwater animals that weigh 30 kilograms (about 66 pounds) or more, such as certain dolphins, beavers, crocodiles, turtles and sturgeons.

Overexploitation is one of the main threats to freshwater megafauna.  (These animals are often targeted for their meat, eggs, and skin).  The other main threat is the loss of free-flowing rivers. Many of the world’s large rivers are already highly fragmented, which impacts access to spawning and feeding grounds.  The research team says another 3700 large dams are planned or under construction, including 800 in habitats rich with freshwater megafauna, including the Amazon, Congo, and Ganges river basins.

Current conservation measures are clearly failing our freshwater creatures. 

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88 percent decline of big freshwater animals

Earth’s largest freshwater creatures at risk of extinction

Photo, posted March 25, 2012, courtesy of the U.S. Fish and Wildlife Service via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Biomimicry Is Big

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Biomimicry is learning from and then emulating nature’s forms, processes, and ecosystems to create more sustainable designs.   Mother Nature is already the inspiration for countless products and designs ranging from Velcro copied from plant burs to the shape of wind turbines modeled after whale fins.  There are wetsuits inspired by beaver pelts and office buildings that copy termite dens.  Increasingly, innovators are looking at nature for designs in architecture, chemistry, agriculture, energy, health, transportation, computing, and even for the structure of organizations and cities.

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Some Good News For Monarchs

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Spring is the time of the great monarch migration when the butterflies leave their wintering grounds in Mexico and head north to Canada.  As we have been saying for quite some time, fewer and fewer butterflies have been making the trek each year.  Twenty years ago, a billion monarchs swarmed the winter site in Mexico.  In 2013, the number was down to 33 million.

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