Because the beaver isn't just an animal; it's an ecosystem!


You heard the news yesterday I assume? I mean other than America’s newest “Lord of the Flies” moment. California must save 30 percent of its land and waters as a buffer for climate change. It’s a lofty and necessary goal. And guess who can help.

Nearly a third of California land must be conserved under new order signed by Gavin Newsom

Citing a need to tackle the growing problem of climate change, California Gov. Gavin Newsom on Wednesday gave the order for state agencies to conserve 30% of state land and coastal water by no later than 2030.

The move is a bid to store carbon in the state’s natural and working lands and remove it from the atmosphere, according to a statement from the governor’s office.

The order directs state agencies to pursue strategies and partnerships that focus on healthy soil management, wetlands restoration, active forest management and boosting green infrastructure, according to the governor’s office.

Now when Rusty of Napa sent me this article with a big grin, I was thinking, hey beavers might help, And then I read this fantastic new study from Canada published this morning.

Beaver dam capacity of Canada’s boreal plain in response to environmental change

Nichole-Lynn Stoll & Cherie J. Westbrook 

Environmental changes are altering the water cycle of Canada’s boreal plain. Beaver dams are well known for increasing water storage and slowing flow through stream networks. For these reasons beavers are increasingly being included in climate change adaptation strategies.

But, little work focuses on how environmental changes will affect dam building capacity along stream networks. Here we estimate the capacity of the stream network in Riding Mountain National Park, Manitoba, Canada to support beaver dams under changing environmental conditions using a modelling approach.

We show that at capacity, the park’s stream network can support 24,690 beaver dams and hold between 8.2 and 12.8 million m3 of water in beaver ponds. Between 1991 and 2016 the park’s vegetation composition shifted to less preferred beaver forage, which led to a 13% decrease in maximum dam capacity.

Which poses the question: if we want more water are we letting beavers dam all the places we should? Of course in California the answer is “No”, Because they could be making a huge difference in our waterways. They go on to point out that the flooding expected as the climate change will blow out those dams, but hey. Beavers will stick around and rebuild when necessary. Because it’s what they do.

Beaver are keystone in supporting food security of Indigenous people residing in the boreal forest through providing a source of meat and being ecologically influential4,5. They are viewed as an ecologically influential species as they profoundly alter the aquatic ecosystems they occupy2 with benefits for freshwater biodiversity6 and terrestrial wildlife7. Beaver alter aquatic ecosystems primarily through engineering activities—dam and canal building—which modifies ecosystem-forming processes8. For example, beaver dams raise and stabilize water tables9,10, alter stream hydrographs11,12, enhance channel and riparian area sediment retention13,14 and create hydrologically complex, multi-channel networks9,15. The suite of changes beaver dams make to aquatic ecosystems creates a multitude of desired ecological feedbacks that collectively enhance ecosystem resilience to disturbance16.

So beaver dams can help with climate changes. But beaver dams are also going to be limited by climate change. As their forage gets burnt out or flooded they will be less able to maintain their complex dam systems. You know any study credited to Cher Westbrook will inevitably have a “Beavers are good BUT” quality too it.

So dams blow out in flooding and beavers can’t repair them without wood. But hey, what about the beavers themselves? Can THEY survive floods? YES. Can they live without dams? YES. Can they have safe homes without  lodges? YES. If their  favorite trees are reduced by a drastic amount can they survive on grasses and less favorite trees? YES.

Beavers can not only survive flooding events. They can bide their time and WAIT for conditions to require dam building and then start over from scratch. Over and over again. And if there are no favorite trees they can use ickly trees, or cornstalks, or rusted engine partss. Hell they can use mud and rocks. They will make it work.

Adaption is their middle name.


Huh, what do you know. There are some nice things to say about beavers in Michigan this morning. This from the River Huron Watershed Council. Congratulations and go figure.

A keystone species at work in the watershed

Flooding caused by beaver dams creates a diverse array of habitats that support insects, waterfowl, fish, and amphibians. For this reason, beavers are also considered a keystone species because their presence in an area can enhance biodiversity and promote the success of other plants and animals in   the ecosystem.

Beaver dams provide other benefits to ecosystems such as erosion control and pollution filtration. Slower flow, coupled with higher water levels upstream, allow pollutants to be filtered slowly through vegetation and breakdown over time. This slower flow also prevents excess sediments from washing into the creek, which can harm aquatic species and contain fertilizers and other chemical contaminants.

That’s a pretty good summation, council. I’m not accustomed to reading very nice things about beavers from your state. It’s a good look for you.

Beaver dams provide downstream benefits as well. The ponds provide a steady supply of water to downstream reaches in dry periods, as water stored upstream of the dam in rainier seasons is released slowly over time. Such changes to river hydrology and the local landscape can occur rapidly when there are beavers present―the “busy beaver” as they say, can build a dam overnight

Of course they can. They are no slackers. And you with all your clam rakes and back hoes you can still barely keep up with us. And that’s the way we like it. Believe me.

Despite the beaver’s contributions to ecosystem diversity, beavers are considered a nuisance in some places. Beaver dams can cause flooding and damage to homes, businesses, and roads. In some small creeks, dams can cut downstream flow to a trickle. Historically, “problem” beavers were exterminated. However, these days efforts are often made to relocate beavers to natural areas where their dam building can contribute to the diversity and vibrancy of our local ecosystems. In the Huron River watershed, beavers are currently very active in Hudson Mills Metropark along the Huron River, where the results of their tree felling are apparent near the walking path. HRWC has also received reports of beavers near Burns-Stokes Preserve, Huron Meadows Metropark, on the river in Huron Township, and in Wixom Habitat Park (Norton Creek, Oakland County). It is exciting to see this iconic rodent back at it in the Huron. An integral part of Michigan’s past, the beaver is once again a part of the watershed’s bright future.

You better believe it mister.


Just in time for the graphic I was working on yesterday, I didn’t know our buddy Ben Dittbrenner was working at NorthEastern. Good for him, and good for the lucky environmental students in his class. For now appreciate an awesome article from News@Northeastern by Khalida Sarwari

They’re cute. They’re furry. And they’re the unsung heroes of wildfire protection efforts.

From California to Washington, the West Coast is experiencing a fire season unlike any other on record. Since August, climate change-fueled wildfires have scorched more than five million acres across the three states, taking dozens of lives, destroying thousands of buildings, and making the air unbearable for millions of people.

Benjamin Dittbrenner, an associate teaching professor in the Marine and Environmental Sciences department at Northeastern, says wetlands and beavers are an important part of the fire protection puzzle. Beaver ponds and wetlands have been shown to filter out water pollution, sequester carbon, and attenuate floods. 

But perhaps a lesser-known fact about the tiny rodents is that they play a key role in creating fireproof shelters for plants and animals. And by building dams, forming ponds, and digging canals, these architects of the natural world irrigate stream corridors that help slow the spread of wildfire.

Ben! My goodness, looking all professor-y, Does that mean we have good beaver researchers on both coasts now? Gosh, I’m so old I can remember when he was working for public works and squeezed in with us at the lunch table so he could hear everything Mike Callahan had to say about flow devices at the beaver conference.

He’s come a long way baby.

One of Dittbrenner’s techniques involved relocating beavers to streams from areas where they were at risk for entrapment. As the critters went to work building dams in their new habitats, Dittbrenner evaluated the transformation of the streams into a wetland complex—multiple wetlands that share adjacent streamside land.

“Wetlands are definitely an endangered or threatened land type,” Dittbrenner says. “There are a ton of existing wetland regulations, but human encroachment is really the biggest threat to that.” 

Dittbrenner traces the degradation of streams and the disappearance of natural dams to the fur trade in the 1600s, which at the time centered on the beaver. Prior to the arrival of the European settlers in North America, he says, beavers existed in nearly every stream system, and dams could be found in abundance. As the beaver population was nearly extirpated because of heavy trapping, the dams disappeared, too.

“As those beaver dams degraded and disappeared, those [wetland] systems became much simpler,” Dittbrenner says. “A lot of the wetlands that were there were gone. A lot of the sediment that was there that was doing things like pollution attenuation was gone. And the flood storage capacity was gone.”

Nicely done Ben. Now we are getting fire skills preached from both sides of the country! Let’s hope it catches on and becomes part of our conversation about how to cope with this going forward.

The resulting decrease in water availability for surrounding plants leads to forest stress, says Dittbrenner.

“[The trees] become more prone to insect infestation,” says Dittbrenner, explaining that forest pests contribute to the fires prevalent on the West Coast. The dams also enable water to back up, producing pockets of both deep and shallow waters as well as rocky, sandy, and muddy habitats for birds, fish, mammals, amphibians, and reptiles, Dittbrenner says. As such, he says, the number of interactions between these species is higher. 

“Beavers are modifying the environment to create their preferred habitat—we call them ecosystem engineers,” he says. “In doing so, they provide all of this traditional habitat for other species, and all of these additional potential ecosystem services for people as well.”

An excellent point. Althought I’m thinking you maybe should at least mention Emily’s work. Maybe you did and the reporter just didn’t write it down, but this issue would hardly be in the limelight without her right?

“As we have these big fires, much of the vegetation in the forest (such as trees) is basically gone,” he says. “And it creates ash and underlying soil easily migrates when there’s precipitation. When there’s a big storm, all that ash and soil will wash—sometimes quickly—down in streams and fill up some of those streams.”

The ash and sediment cover salmon egg nests, he says, causing the eggs to suffocate because they can’t get enough oxygen. The absence of trees—which help slow down river and overland flow—leads to an uncontrolled surge of water following rainfall and increasing stream flows, which puts added stress on man-made infrastructure, such as bridges and wastewater treatment plants, Dittbrenner says.

You know looking at the great photo by Joe Wheaton I don’t think that beaver dams burned. Which means they stuck around and helped catch all that erosion and soil runoff. Just another service amount their many provided.

And not just aquatic species, he says, but trees lose water as well. The stress makes them more prone to disease and insect infestation. This systemic stress creates what Dittbrenner calls a “positive feedback mechanism” that often results in environmental disasters.

“If there’s a fire, those trees might already be dried out; some might be dead,” he says. “And that standing fuel load allows for increased forest fire prevalence.”

Research shows that healthy streams promote aquatic life and nurture surrounding lands. Dittbrenner’s work provides clues to how beaver ecosystems and wetlands fit into that equation—and contribute to wildfire protection and recovery.

Well, those are good clues to have. It’s great to see this discussed more broadly, and I hope Ben gets lots of interested undergrads to help him carry on the work. In the mean time here’s the graphic I worked on yesterday. Feel free to share.

 


This was such a quirky article that I left it on the shelf a while before revisiting it this morning. It remains a mystery to me WHY we need a dog to do this or when we would have the need to track down a specific beaver, but it’s pretty darn fascinating to think about the complex information beavers have at the disposal of their sniffing any given day.

Conservation dogs have been trained to locate animals both dead and alive. Given that dogs’ sense of smell is approximately 10,000 to 100,000 stronger than ours, they are excellent partners for tracking animals in the wild.

With the help of three “scent detection dogs” named Tapas, Chilli, and Shib, researchers have shown that with persistent training, this olfactory advantage could dramatically improve conservation canine handlers’ work. How? By improving upon their ability to identify animals by tracking their individual butts.

Well obviously any dog owner knows how important that sniff is to greeting a new dog. But it’s easy to overlook how much valuable information is coded in castoreum for a beaver.

Since these beavers communicate primarily through scents, they’ve invested quite a bit of evolutionary development into their anal glands. In fact, the anal glands are not the only butt-local organ that beavers use to make themselves known to their neighbors. They use two, each of which is located between the base of the tail and the pelvis: castor sacs, which produce a brown mucous called “castoreum,” and anal glads, the “true” glands which produce AGS. AGS is a “thick gray paste” in female butts and a “yellowish oily fluid” in males. AGS contains a great deal of information about an individual beaver, including species and subspecies, sex, identity, kinship/family role, age, and social status.

Read that list again, species and subspecies, age, sex, kindship or family role AND social status. I’m not even sure what that means but I guess if you’re the matriarch of a colony you smell different than just some daughter selected at random. Years ago when our mom beaver died and the kits were orphaned, dad left for a while and came back with a two year old from our family that had already launched: the one we always called GQ because we thought “he” was such a handsome beaver. The two year old stuck around, and helped raise the kits. And I always wondered how Dad found him.

Now we know.

They use two, each of which is located between the base of the tail and the pelvis: castor sacs, which produce a brown mucous called “castoreum,” and anal glads, the “true” glands which produce AGS.

After the 9-month training period was complete, the dogs’ sniffers – and the identifying potential of AGS – were put to the test: Six vials in total were lined up, including four AGS samples, one distraction scent, and one blank. Tapas, Chilli, and Shib were each subjected to ten trials. The results were stunning. Each dog showed themselves to be beyond capable of finding the precise beaver by their anal excretions alone.

Not only are these findings a clear demonstration of scent detection dogs’ ability to extract highly specific information from AGS, but it also points to the incredible reliability of the Eurasian beaver’s hind-centric olfactory communication system.

Okay good job dogs. But Better Job Beavers. For evolving this amazing classification system and making it work. Just think of the time and awkward conversations it saves. Beavers never have to ask, “Are you knew here?” They never are surprised to find out they hit on a married woman, OR discover their new love interest is their second cousin. They already knew.

23 and me has NOTHING on them.

By the way, I don’t think we guessed wrong about GQ’s gender. Because he did not stick around and dad eventually brought back a new wife that no one recognized. Apparently he agreed to help out for a while to get the kids settled and then took off in pursuit of his own future.

I’ve always wondered what it was.

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Nature Scot has launched the largest beaver survey asking folks at the national level to report beaver sightings. Mind you they released permits to kill 20 percent of the known population last year. But they’d now like to know, was it enough? Should we kills more?

20 percent isn’t what it used to be.

Biggest ever Scottish beaver survey begins

NatureScot has begun the most comprehensive survey of beaver numbers and their range ever conducted in Scotland.

Work was expected to start on October 1 to gather detailed and up-to-date information on the locations of active beaver territories, as well as assessing the health and spread of the overall population, which will help inform future beaver work.

It is thought that since a first assessment in 2012 beavers, other than those introduced to Mid Argyll in 2009, have spread from where they originally established on the Tay, as far as the Forth and the Clyde.

 

The nature agency is asking the public to help by reporting their beaver sightings.

Mind you this is a “Survey” like a field survey, not a “Man on the street how do you feel about beavers” survey. Odds are they are going to do something very stupid like count the number of dams, multiply it times 5 and come up with a hugely inflated number which means more killing next year.

But what do I know?

Captive European Beaver (Castor fiber) Highland Wildlife Park, East Highland Area.
©Lorne Gill
For information on reproduction rights contact the Scottish Natural Heritage Image Library on Tel. 01738 444177 or www.snh.org.uk

The survey will cover Tayside and the surrounding river catchments, including the Forth and river systems in the Loch Lomond and Trossachs National Park. NatureScot will be working with experts at the University of Essex to conduct the survey this autumn and winter.

This is the first survey conducted since beavers gained protected status as European Protected Species in Scotland.

Roo Campbell, NatureScot project lead, said: “From sightings so far this year, it looks like beavers are spreading even further in and around Tayside – there’s even been a beaver spotted in the west of Glasgow. This is wonderful news, as beavers play a vital role in creating habitats such as ponds and wetlands where other species thrive, alleviating flooding and improving water quality.

“But sometimes beavers can cause problems particularly on prime agricultural land, which is principally found on low lying farmland particularly in the east of the country.’

And when they do we’ll be ready for them. We shall fight them on the beaches. We shall fight them in the fields. Never give up. Never surrender. Always say die.

Er somethings like that,

 

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