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

Category: Beaver Behavior


I may be prejudice but I don’t appreciate calling predators ecosystem engineers because they decide where restoration is OVER. That’s like saying your father always made the family meals because he decided when it was time to fast.

Maybe I’m old fashioned but I just think ecosystem engineers should you know, engineer ecosystems. You know?

Beavers Are Ecosystem Engineers, But Hungry Wolves Limit How Far They Influence

The relationships between animals and the environments that they live in are incredibly varied and complex. While the predator-prey interactions are probably the most well-known, each species also has an influence on the other flora and fauna and even the soil in the surrounding areas. Foremost among these influential species are beavers: they are known as “ecosystem engineers” as they reshape the forest around them by felling trees and creating wetlands. One predator of the beaver (Castor canadensis), the gray wolf (Canis lupus), has now been found to influence the foraging habits of the beavers and thereby affect the forest structure.

Foraging and finding food is an important part of every animal’s life. Beavers typically leave their dams on the water and forage on obvious feeding trails that they have created by moving trees and branches through the forest, before returning to the same area. This is known in ecological terms as central place foraging, as the beavers always forage outwards into the forest and then return to a central place. 

Previous studies have shown that beavers are limited in how far they will travel from the safety of the water because of an increase in predation risk as they move further away. However, there has been no evidence that the wolves hunt or kill beavers that venture further away from the waterside – until now.  

Wolves are known for hunting a wide range of species, from moose (Alces alces) and caribou (Rangifer tarandus) to fishing and even predating on seals and sea otters. Where the ranges of beavers and wolves overlap, wolves are the primary predators of beavers. While wolves are usually known for their ability and stamina to run long distances chasing large prey, wolves are also effective ambush predators when it comes to beavers.

Yayaya, everybody likes to talk about wolves ambushing beavers. It’ll probably be a Christmas special soon.

The study found that wolves are more likely to predate the beavers that travel further away from the water on the longer feeding trails. Because of this, the wolves are directly affecting the forest structure by limiting how far the beavers travel away from the water to fell trees and forage. 

Thomas Gable, lead author of the study and project lead of the Voyageurs Wolf Project told IFLScience that “based on the distance that wolves killed beaver from water, that beavers would forage an additional 9-18 m [29.5-59 feet] from water on average if wolves were not around. Of course, this is a coarse estimate and we were simply trying to get a rough assessment of the extent to which wolves might be constraining beaver foraging behavior toward water.

“In this study, we estimated that wolves could be influencing the structure and composition of 23-47 square kilometers [8.9-18 square miles] of forest, which translates to 1.4-2.9 percent of the forest in our study area. But this was a rough estimate and just an attempt to estimate the general magnitude of wolves ecological impact.”

The beavers have been known to create what is called an ecological “halo” around the area where they typically forage because they forage around a central place. The beavers alter the forest by felling trees around the central place; they then create gaps in the canopy which allow different tree species to grow.

Beavers also have a preference for felling deciduous trees rather than coniferous trees, which can create a halo of evergreen trees around the water as seen in this image below. The team says the area would be larger if the wolves were not present in the ecosystem

Ecological Halo!!! How much do I like that phrase! Beavers are like angels spreading their good deeds all around the perimeter of their pond. Only those little devil predators can stop them.

Overall, the team found direct evidence that the wolves limit how far from the water the beavers will forage and, in doing so, limit the effects of the beavers’ ecosystem engineering on the habitat they both share – and that the same process could be happening across the world.

“We think the patterns and trends we found likely do occur in many other areas where wolves and beaver co-occur across North America, Europe, and Asia. There are others in the scientific literature that have noted some of the same patterns regarding how far from water beavers will forage in areas with and without predators so we suspect the pattern we identified is not unique to Voyageurs. Hopefully this work will inspire others to go out and study wolf-beaver interactions to see if we are correct about that,” finished Gable.

Hopefully more places will come to tolerate beavers so that they can sprinkle those halos around in more places.


2024 Conservation Stamp Art Contest Winner Justin Hayward, Casper, WY

This was nice to come across. Enjoy!

Between the removal of the dams downriver that will force colonies of bats to be relocated to allow the salmon to return upstream or the creation of fake beaver dams to inspire the little engineers to help improve water quality and fight forest fires, water is a hot topic in the Klamath Basin. Beavers in particular will change the way our water system works and on Monday we have an interview we shot with Gus Wathen who is in charge of the team on the Sun River building man-made beaver dams to help inspire beavers to return the the region and help restore our rivers. Here is that interview!


Do you remember that one kid in elementary school who did everything perfectly? Got straight A’s. raised their hand everytime with the right answer, had amazing homemade costumes every halloween, colored in the lines and always had the best toys with no broken parts and new batteries, the most friends and they newest clothes? Maybe your parent even said “why can’t you be more like that?” and you wondered y0urself more than once.

And then do you remember how it felt when everyone went to fifth grade camp and they fell in that puddle that soaked them in mud from head to toe and they had to go home early because they couldn’t stop crying? Well that’s how I felt when I saw this article.

Oh how the mighty have fallen.

Beaver family that moved into Seattle’s Carkeek Park may complicate salmon-spawning journey

Called by the sound of flowing water and ample trees, a family of beavers have moved into Carkeek Park, building a series of dams along the mouth of Pipers Creek.

The largest dam — which incorporates a fixed park bench and two large trees — has widened and grown to the degree that water is spilling on to a walking trail nearby. The dam, reinforced with mud and branches, also may present a challenge for chum salmon, which are set to return and spawn at any moment, said David Koon, the salmon program director at the Carkeek Watershed Community Action Project.

It’s not clear yet how the beaver dam will impact the spawn, he said, and some of that will depend on how much and when it will rain this season. Beavers build dams to create a pond where they can build a “lodge” to provide protection from predators.

Mind you. This is SEATTLE. Where NOAA fisheries is head quartered. Where Michael Pollock works. This is the smartest state about beavers in the entire universe. And he is worried about the chum.

In a natural environment — where a river flows consistently all the time — a beaver dam would be no problem for spawning salmon, he said. But Pipers Creek, surrounded by a highly urbanized and concrete-laden watershed, is no natural river.

Even without beavers, the survival rates of the salmon’s eggs are low at Carkeek Park, he said. Due to the nonporous nature of the watershed, the stream’s depth often increases and decreases rapidly before and after rain, leading the eggs often to be washed out. Plenty of other things like runoff from fertilizers, tire dust and dog poop also threaten the eggs.

While beaver dams can sometimes help salmon eggs, slowing down water and filtering silt, the ones in Carkeek Park may prevent the salmon from traveling fully upstream. If the downstream waters are high enough — which they aren’t right now — Chinook and coho salmon can jump over the dams and the chum can beat their way through the gaps, Koon said. Otherwise, the salmon will have to wait for when the water levels get high enough during active rain.

You see what I mean about knowing better. The idea is they know beaver help salmon. Just maybe not these salmon. Never mind that the creek probably wouldn’t have deep water at all if the beavers weren’t there. Never mind that it is perfectly normal for salmon to wait for storms and swim over during high rain. Never mind that waiting might even connect the, to more salmon so they can find a mate. in the first place.

Parks and Recreation intends to apply for a permit to install a device within the dam that would drop the water level, and may also implement fencing to protect trees. The beavers, which likely came over from Golden Gardens, may be relocated, she said.

Standing next to a 2-by-6-inch plank built into the largest dam, Koon estimated the dam’s length is more than 50 feet and the depth of the pooled water is at least 5 feet. Koon, who has kept an eye on the salmon at Carkeek Park for years, said he’s seen small dams at Pipers Creek likely built by young inexperienced beavers that get washed out after one big rain in the past.

“These ones are clearly experienced,” he said. “They’ve done some really good, amazing engineering.”

That’s right the novice beavers aren’t a problem for salmon because they only build  little dams and those get washed out. But these experienced beavers build 5 feet dams and that ruins everything.

Hey you know how tall the Martinez primary dam was when the city first measured it? 7 feet! And do you know what that concrete channel did to the steelhead population? NOTHING. In fact at one time our beavers had five dams. And some were big and some were little and it had nothing at all to do with their experience level.

This year, as the stream has moved and broken through some of the smaller dams, he’s seen the beavers expand and lengthen the large dam, patching up sections overnight. Koon said the two adult beavers and a “kit” or baby beaver have had additional baby beavers since moving into Carkeek.

Oh noo. You mean you have those very rare REPAIRING beavers that teach their children how to help fix and strengthen dams over time? That almost never always happens.

I have a few videos that might interest you.


See how this works? You have no need to fear the boover. Happy Halloween by the way.



Wishing you a tailslapping Sunday. Robin suggested I edit this to make it more accurate.

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