Archive for the ‘Beaver Behavior’ Category

To Beaver or Not To Beaver?

Posted by heidi08 On May - 25 - 2017ADD COMMENTS

More silly mulling from the Scottish countyside: Should beavers be allowed or not? A reader on the Tayside group pointed out that this same argument could have been made 15 years ago, I say probably longer than that.

Beaver reintroduction – what’s the story?

Their reputation as strong swimmers and prodigious engineers is not an understatement. Their large incisors and clawed front feet enable them to construct dams and lodges that can extend for hundreds of metres, as well as burrows of up to 20 metres into the riverbank.

“Any species introduction, particularly if it has not been in this country for hundreds of years, can have a massive impact on the many benefits that the countryside delivers,” Mark Pope, an arable farmer from Somerset who has instigated numerous initiatives to provide habitat and food for birds and insects and encourage diverse plant species on his farm, said.

“In the case of beavers, the NFU has concerns about the damage to farmland and the landscape caused by their physical activities.” Mark, who is also chair of the NFU Environment Forum, added. “Farmers and the public must have the tools to manage the impacts beavers will have to farmland, the countryside, flood defences and urban areas.

“Beavers can add biodiversity, as well as the interest, enjoyment and socio-economic benefits they can provide to many people. What the NFU is very clear on is that in some locations there is a clear need to manage this species to minimise undesirable impacts on agriculture, forestry, inland waters and other land uses.”

There is increasing interest in the beneficial role beavers could bring to habitats. The natural activities of beavers could help to regulate flooding and improve water quality, if managed properly. The Devon trial on the River Otter, led by the Devon Wildlife Trust in partnership with Clinton Devon Estates, the University of Exeter and the Derek Gow Partnership, has been exploring the role of beavers in managing and creating wetland habitats, the impacts on water quality, and influence on water flow and flood risk.

Tolkein once wrote “Go not to the elves for council, for they will say both ‘No’ and ‘Yes’.” Mostly no, though.

On the other hand, beaver burrows near watercourses can weaken river embankments and flood defences. Material felled and gathered by beavers for dams and lodges can create flood risk downstream and block drains upstream. The potential consequences of this for farmland and the rural economy is a cause for concern.

It is estimated that the costs of the 2007 and 2013-14 floods on agricultural businesses alone were £50m and £19m respectively, not to mention the wider economic impacts on local employment, infrastructure and utilities and the damage caused to people’s homes and communities.

The knock-on effects can be wide-ranging. The loss of productive farmland, for instance, would have a detrimental effect on food production and supply.

The Scottish Beaver Trial was a five-year project between the Royal Zoological Society of Scotland, the Scottish Wildlife Trust and Forestry Commission Scotland to undertake a trial reintroduction of beavers to Knapdale, Mid-Argyll. The trial concluded in 2014 and as a result the Scottish government is considering recognising the European beaver as a native species.

A change in the legal status of beavers raises additional concerns. This is because beavers have no natural predators in the UK so it is important that populations can be managed, particularly if they are present in extensive low-lying areas such as East Anglia, Wiltshire and the Somerset Levels where their activities could block field drains leading to waterlogging (known as ‘wetting up’) of productive farmland.

Clarification: Beavers might benefit us if they don’t kills us all first.  “We killed off all their natural predators in the UK so there’s nothing left  to kill them and their numbers will swell like taxes with national health”. Are there no otters? No bacteria? No vehicles in your land? Beavers just don’t get killed by predators you know. And honestly, why act like you want to explore an issue and ONLY speak to one farming fiend from the National Farmers Union?

Who’s going to list all the many benefits for fish, wildlife, birds and water storage that come with beavers? Who’s going to talk about how much you can learn about nature by watching them? Who’s going to say how much they improve the health and vitality of urban waterways?

We need a National Beavers Union!!!



Gifts of May

Posted by heidi08 On May - 24 - 2017ADD COMMENTS

Old bedding: Rusty Cohn

Once upon a time I was surprised to read that beaver change the rushes on their lodge floor every week or so. Mostly because that’s more than people did in the middle ages. But Rusty was lucky enough to come across the activity last evening at the beaver pond in Napa. I seem to remember that this is the time of year I saw it most often, obviously having babies muck up the place must make it dirty faster. When Rusty got to the pond last night he saw this:


Carrying in new bedding: Rusty Cohn


After watching for a while he saw a beaver gathering up some of the cattails and then swimming with them into the lodge. The original changing of the guard.

Apparently in the winter months, when there are no fresh grasses or cattails they rely on
woodchips. I’m trying to imagine

why, because it can’t be comfortable. Maybe it’s like elephants covering themselves with dust and it help keeps insects away?


Rusty Cohn

I’m not sure, but I know that  May is an EXCELLENT time for beaver watching in the bay area. Rusty has been watching the pond spring to life. And years ago it was when I was lucky enough to see this:

(The records say it was May 3rd, nearly 5 weeks before we had ever seen a kit in the evening, so you can imagine why we were so surprised!)


Be Careful Out There

Posted by heidi08 On May - 17 - 2017Comments Off on Be Careful Out There

Beavers are notoriously vulnerable on roadways. They are low to the ground and usually crossing in the dark which makes them a prime target for roadkill. image002Do they ever use wildlife crossings? Inquiring minds wanted to know. Some fine investigative beaver reporting comes from Robin Ellison of Napa. She was interested in whether beavers ever use the crossings trans Canada offers. You know the ones I mean.

Turns out they have an extensive system to document the wildlife crossings with trail cam footage, and trackpads keep records to monitor use. They were only too happy to share the info with Robin and wrote back:

Thank you for your inquiry and interest in the wildlife crossing structures as they relate to beaver species movements.  I’ve had our database specialist look through the history of wildlife crossing documentation and have found some results for you.  We’ve not been able to find documentation on whether or not road mortality numbers for beavers were affected.  However, we did find information on beavers using the Trans-Canada highway wildlife crossing structures.  There are only 5 incidences that have been documented on all of Banff National Park’s highway wildlife crossing structures (we currently monitor 44 of these structures).  As you mentioned, all the beavers that have been documented on wildlife crossing structures were associated with waterway travel–in these cases the beavers were on a flat pathway in an underpass that has a creek running through it.

Below I’ve listed the information we have on beavers using the Trans-Canada highway wildlife crossing structures.  I’ve also found a photo of a beaver using a wildlife crossing structure (you can see the creek in the background).   

Screen shot 2017-05-17 at 6.07.19 AMNot a ton of observations, beavers are probably less likely than others to venture out of the water. But there are more observations than I might have expected. You can see three identifications came from trackpads which I had to look up. Here’s a nice description from some research they did trying to find which tool worked better. They found that trackpads had their place but cameras were better if there was a lot of wildlife traffic.

Field Data Collection
All 24 CS in the study area were continuously monitored forlarge mammal use since 1996 using track-pads (Clevengerand Waltho 2000, 2005). At least one track-pad (range 2–7pads/CS) was constructed at each end of every underpass,and each track-pad spanned the width of the underpass and was approximately 2 m long in the axis of animalmovement. Track-pads on the overpasses consisted of onetrack-pad located at the center, spanning the width, and were approximately 4 m long in the axis of animalmovement. Tracking material consisted of a dry, loamy mixture of sand, silt, and clay, 1–4 cm deep. We visited eachCS every other day, and at each visit we classified thetracking medium as Good, Fair, Poor, or Too many,depending on our ability to detect tracks. A track-padcondition of Good occurred when our ability to detect tracks

Here’s what one of the cameras documented. That lucky beaver made it safely across and back into the water. (The darker area is the creek). Beaver_external distribution ok

I haven’t been doing this beaver work for very long, but I’ve already come across several beavers and otters struck by vehicles. We could learn a lot from our Canadian friends. Thanks to the helper who shared this information

J. Kimo Rogala, M.Sc.
a Resource Management Officer II
Ecological Integrity Monitoring, Banff National Park
Parks Canada Agency | Government of Canada
Box 900, 216 Hawk Ave, Banff, AB, T1L 1K2

for keeping track of this information. And thanks Robin for doing the legwork! This is a wonderful insight into something we understand very little about. I’m just glad these beavers never had to go through this:

(For the record I spoke years ago with the fellow who filmed this beaver. Not the news site  that made his footage into a comedy. And the witness swears he made it across safely. Although one foot did appear injured in the photos I saw.)