Archive for the ‘Beavers’ Category

Above and Beyond

Posted by heidi08 On December - 15 - 20141 COMMENT

Lake Elmo beavers: Cute, yes, but something of a nuisance


It might look like the middle of the wilderness, but this beaver was photographed after a recent snowfall on the west side of Lake Elmo in the Heights. Photographer John Warner has been taking pictures of this beaver and two others this fall.

  Three or four beavers—one or two adults and two kits—have built themselves a home on the shores of Lake Elmo in the Heights.

Their bank den is on the west side of the 64-acre reservoir, near the boat launch and right alongside a culvert that feeds the lake with water from the Billings Bench Water Association canal. A bank den is similar to a lodge but incorporates the bank surface into the structure.

Only three beavers at a time have been spotted so far, but Dave Pauli, with the Humane Society of the United States, said beavers mate for life, so there is most likely another adult in the den.

Terri Walters, who manages Lake Elmo State Park, of which the reservoir is part, for the Department of Fish, Wildlife and Parks, said the beavers apparently migrated to Lake Elmo from the nearby irrigation canal sometime this fall.

 The beavers have already felled two small cottonwood trees, a willow and a Russian olive, and they have been working their way through a willow stump thick with dozens of shoots, including a few large ones. They have stacked the top of their lodge with branches, which they will feed on throughout the winter.

 Walters said she had to wrap 10 other trees with wire so they beavers wouldn’t gnaw on them.


Don’t tell me you actually had to take such extreme measures to fend off these marauders! Actually wrapping trees? That’s like having to put your car in the garage or your wallet in your pocket! I mean it’s not quite as bad as wearing a condom or keeping a receipt, but my God, how much can one woman take?

beaver and kits in snow

An adult beaver and two kits swim in open water. John Warner

Pauli also said he’d like to work with FWP on a plan that would allow the beavers to stay at the lake. The adults could be spayed and neutered, and the kits could be as well if they stayed on. Lake Elmo State Park is often visited by groups of schoolchildren, Pauli said, so it would be good learning experience to have a family of beavers living where they are so easily accessible.

The article was going along pretty much like I expected but this was a coffee-spitter. HSUS Dave Pauli thinks the beavers should be neutered? You do realize that kits disperse and move away on their own, right? I mean here in Martinez we’ve had 20 born in 7 years and our population is still 6. I hope you don’t think that beavers can get neutered as easily as cats. Males and females have internal sex organs, and they might not survive the stress of capture even if it were possible.

What a very scary thought. It might well mean that sadly, sometimes the Human Society of the United States has absolutely no idea what its talking about. I always thought of them as smarter  and better than me. Like Jane Goodall,  Gandhi or Mother Theresa.

But even more importantly, let me just say that John Warner’s remarkable photographs of this beaver family are among the most beautiful images I have ever seen. And that’s saying something. Why not use these urban beavers and remarkable visuals to promote the first ever beaver festival in Billings Montana? It would teach locals how and why to work with the animals, and improve water, hunting, and fishing in the area.

beaver reaching snow

A beaver stands on its hind legs to get at snow-covered branches. John Warner

Now this came yesterday from our friend Lee Ann Carver, the wildlife photographer in Canada. You will of course appreciate what happens on the twelfth day of Christmas, but the fifth is pretty clever too. Pass this along to your friends. See it you can spot Grey Owl and if we can top 1000 views by tomorrow.

Oh and a sad correction from our retired librarian friend in Georgia, who pointed out that beavers might not actually get to heaven after all. Dam it.

Pope Francis turns out not to have made pets in heaven comment

Just in time for a Nativity Scene!

Posted by heidi08 On December - 9 - 2014Comments Off

Iwaterboards‘ve been hard at work on my presentation to the waterboard next week, but I had to add a new section on our papers about historic prevalence for this particular audience, and I didn’t want to lose much of my original info so I wanted it to fit in five minutes. This meant I couldn’t wander about looking for the words so I wrote a little passage to insert, that I thought it could double as a post. Hopefully it will be new to you or at least interesting.

Martinez was eager to teach other cities in California what we learned. But before we could really share the wealth we had to deal with a 70 year old mistake. The confusion started with Joseph Grinnell, the first director of vertebrate zoology at UCB and the author or the important work on the states fur-bearing mammals. In his chapter on beavers he noted that they didn’t live above 1000 feet in the Sierras and were absent from our Coastal Rivers. According to Grinnell beaver didn’t belong in Tahoe or Berkeley and before we talk about how this was possible I need to say a little bit about the history of the fur trade.

Just like our thirst for oil has driven the economy and the politics for that last century, our need for beaver fur was the “oil” of the previous 800 years. Beaver were so important to trade that they were entirely trapped out of Europe by the end of the middle ages. The Russians trapped the California Coast in the 1700’s. Folks came to Canada looking for new sources of the valuable fur and trapped west and south at a great rate. Beaver were extinct on the East coast of America by the 1800’s and sought steadily west by the French, the Dutch, and the Americans. By the time that the 49ers arrived in them thar hills looking for gold in California the once ubiquitous beaver gold was long gone.

In 1900 there were nine known colonies of beaver left in CA. Fish and game, to their credit was concerned that zero beaver would mean more erosion, fewer fish and less waterstorage. They began a period of reintroduction in the late 20;’s and 30’s. This lead Grinnell to think that beavers in the sierras or coastal rivers were introduced, rather than reintroduced. We were particularly interested in this confusion because it lead people to say that beavers weren’t native. We wanted to challenge that idea.

MistakeThe first place we started was with the work of an archeologist at the Bureau of Indian Affairs. He came across a paleo beaver dam during a dig in the Sierras and had the sense to carbon test three parts of the dam. As you can see the oldest tested at 580 AD and the dam was continually maintained until the 1800’s. We then looked at secondary data including anthropological information, place names and a reevaluation of trapping records. We found numerous evidence to contradict Tappe and Grinnell. This Rock painting by thedited chumashe Chumash Indians is at 1600 feet above Santa Barbera, The Emeryville Shell mound contained beaver bone fragments, After his good service Kit Carson was rewarded with the right to trap all beaver in Alameda Creek.

The fossil record for beaver contained a skull from Sespe creek in Santa Barbara that didn’t ft with Grinnell’s theories, so he marked on his map with a question mark. Recently digitized correspdence however made available to us the letters better Naturalist John Hornung and his friend Dr. Grinnell. He wrote that he himself had found the beaver in question floating down the creek on a log, and like any good naturalist of the time would do with a rare animal, killed it himself and sent off the skull.

At this time the book was already in press and this discrepancy was dismissed. The misreport of Grinnell was copied by every other author and taught in science classes for 70 years.

Mistak1eWhat do you think, convincing? If you want to read more the links to these published papers is in the right hand margin about halfway down the page under the section “Solving problems”. Happy reading!


The Scottish Beaver Trial Report

Posted by heidi08 On December - 5 - 2014Comments Off

  Scottish Beaver Trial publishes its final report

The Scottish Beaver Trial, the first formal reintroduction of a mammal ever to take place in the UK, has published its final report. The five-year-trial, at Knapdale forest, Argyll, is a partnership led by the Scottish Wildlife Trust and the Royal Zoological Society of Scotland.

 The first Norwegian beavers were released in Knapdale in 2009 and monitoring ended in May. This report will help ministers decide on the future of beavers in Scotland.


Now this is worth curling up and reading next to a good fire with a cup of hot chocolate. Or maybe Scotch. It’s a huge file and is taking forever to download but the entire thing is accessible here and you can count on me for some highights. I thought it was impressive but  Victor Clements just scoffed that its mostly presentation with little information. I was interested in details of the beavers lives.   Here’s the family tree, (ours is so much better!)

CaptureThe first thing that really caught my eye is that the trial site turned out not to be secure and maybe some of the beavers got away into the sea!! (Which our friends of the River Tay Beavers should find fascinating!) They installed a kind of flow device in the first dam and then realized it didn’t matter if the pond flooded! I was also interested to learn that two of their kits were predated, one by a fox and one probably by a large domestic dog. This surprises me not at all, but is worth remembering the next time someone says beavers don’t have predators.


Two kits were also found predated during the course of the Trial. One of these was a Dubh Loch kit found dead on 8 September 2011 in shallow water at the edge of a flooded track at the marshy eastern end of the loch by the SBT Field Officer while carrying out a routine field-sign survey. The cadaver was collected and taken for full post-mortem examination, which indicated that the beaver had been in good body condition but had died as a result of traumatic injuries to the head, possibly caused by a large predator. Although unconfirmed, it was felt by SBT staff that this could have been caused by a domestic dog–a diagnosis strengthened by later comparison with a kit killed by a fox. The second kit was found on Loch Linne by researchers from the University of Stirling, who were undertaking vegetation transects as part of their annual data collection. This kit was quite badly decomposed, and all internal organs were missing, so full post-mortem examination was not possible, though from the location of the puncture wound and marks on the bones it was presumed that this individual had been predated by a fox.

 Remember that these beavers got “injected, inspected, detected, dis-infected, neglected and selected.”They had Ear Tags, tail radios and GPS systems on their backs. They were weighed, sexed, measured and monitored at regular intervals. Their private moments were caught on film and they still managed to elude the researchers at times.  Dispersal, it seems was really hard to catch, and the first and second year it didn’t happen at all. Population density seemed to really effect behavior because where there was only one male at Dubh Loch the father (Bjornar) surprised everyone by mating with his own undisperssed offspring (Mille) who went on to have several kits. This is not totally unprecedented, but theu didn’t exactly issue a press release!

Capture23And speaking of press releases, there is an entire section on how they educated the media and the public for this monumental undertaking. They really included public support at every level and I am not at all surprised it worked for them. This is a great learning activity they did with the lower grades that has me thinking about the beaver festival! They made sure there was accessible, inviting viewing for the public Captu4reand encouraged visitors. They did what they could to bring the public along with them and make sure everyone understood where their tax dollars were going. There’s a very good reason why the Scottish Beaver Trial received an award for being the best Conservation Project of the year.


The report concludes with these exciting remarks:

The authors of this report, along with many others across Scotland, Wales and England, look forward to the coming months when a decision on the future of beavers in Scotland will be made. Perhaps one day we shall see the widespread return of this native species to our lochs, rivers and burns.

Worth A Dam welcomed the trial in 2009 and is proud of its conclusion in 2014. And when you watch this inspiring baptism think about how much bigger our festival is now.

Oh, what a relief it is!

Posted by heidi08 On December - 2 - 2014Comments Off

When I sat down with the numbers of depredation permits issued in California, one fact in particular kept catching my eye. The number of permits issued for Placer county. Contrary to expectation, it doesn’t have more water, or more people, or more culverts.  It consists of seven towns (Auburn, Colfax, Lincoln, Roseville, Rocklin and Loomis) and about 20 unincorporated areas which all have more permission to kill beavers than anywhere else in the state. Nearly 7 times more, which turned out to be significant at the p =<.02 level. This, in case you didn’t take statistics, pretty much means it ain’t random.

So I thought I’d write the two charming representatives from Placer county who wrote them and say, hi my name’s Heidi and I’ve been looking at the depredation permits for beaver in California and I’m curious why you issued a third of them.  Any thoughts? And I was more polite than I wanted to be, but still expected to hear nothing back.

To her credit, the most active member of the beaver-killing squad wrote back. She said Placer county has grown faster than any other region in the state, and permits to kill beavers are issued under 4181 which says that when property is damaged or (threatened)

The department, upon satisfactory evidence of the damage or destruction, actual or immediately threatened, shall issue a revocable permit for the taking and disposition of the mammals under regulations adopted by the commission.

 She said we assess the situation and educate where we can and grant permits when necessary. What she did not say, and which I was dying to know, is what consisted of satisfactory evidence (a site visit? A photo? A phone call?)  and how often did she actually turn down the request, telling the property owner to try something else?

(I’m guessing it’s a round number.)

She also thanked me for the resources I sent but said she already knew all about “beaver relievers” [sic] (Cross my heart – RELIEVERS she called them.) And I was sure it was a typo, or an UH-OH, but when I wrote Sherry Guzzi she pointed me to this paper by Colorado USDA scientist Nicholas Gerich, who (back in 2003) wrote a paper called “Working with beavers”, in which he outlines the pros and cons of several flow devices which he calls (wait for it!) “beaver relievers.”


Many of these solutions work well only if regularly cleaned. When these devices are not regularly inspected and maintained, they will fail with potentially disastrous results. Too many people think that once the device is installed that everything is solved and they can walk away from it.

 It seems Nick was not very impressed with their success rate and said they had to be onerously maintained to even have a hope of working. But given his location I was curious if he’d ever met Sherri Tippie so I emailed him and asked. He said he had taken a class with Sherri shortly before that was written, and had gotten interested in the work when the beaver population “exploded” after the 1996 law. (Deja Vu much?)

exploding beaver

In his experience flow devices “worked in some places” but “not in others”.

Now I know exactly how much maintenance our flow device has required, (none) but I didn’t know if it might have worked less well in Tahoe or Colorado, so I asked Mike and Skip. I particularly liked what  Skip said,

As for the “physics” of the issue, beaver behavior and the properties of moving water are largely the same everywhere.

Now as to that exploding beaver population, I was particularly interested since I had learned that very refrain in Massachusetts many times. You can imagine how happy I was to see this in the paper yesterday from the Prescott Peninsula beaver count

 The beavers are all right: Data returned from survey at restricted Prescott Peninsula

Researchers from the Department of Conservation and Recreation, along with affiliated volunteers, conducted the annual Prescott beaver survey Nov. 16 at the Prescott Peninsula — an area usually off-limits to humans. The survey data, which was compiled last week, shows 15 active inland beaver sites.

 And they ran this:

Real numbers in MA

I know graphs can be hard to read, but that high pointy part on the left shows the highest density of recorded beaver population in 1980. For us following along at home that was 16 years before voters insisted on those pesky humane traps.  The population went up a little after 1996 but settled out with much lower levels than it used to support. Mind you this is just a particularly lush, inaccessible region in the state. Not the whole state. But knowing how beavers feel about trees, water and privacy we can guess its at least equivalent to what we would see all over if anyone was looking. Which means that every single person who tells you that the population of beavers exploded after they made conibear traps harder to use, should look behind them to see if their pants are on fire:



Glass Farm Beaver YS Ohio – photo Scott Stolensberg

A final update from the photographer Scott Stolensberg who graciously gave permission for me to use the photo and was so supportive he wants to donate to the silent auction! Thanks Scott!

Beaver through the Looking Glass

Posted by heidi08 On November - 28 - 20142 COMMENTS
And bring hither the fatted calf, and kill it; and let us eat, and be merry
 For this my son was dead, and is alive again; he was lost, and is found

Ohio is one of the states that I have nearly given up for lost when it comes to beaver management. Along with Pennsylvania and Oklahoma I’ve come to regard them as ecological wastelands, mostly devoid of kindred spirits who care about nature. I’ve unkindly assumed that Ohio is the state where conservation (and most recently 17 tigers) go to die. Think of a famous naturalist from Ohio. You can’t, can you? In 7 years of covering beaver news I have read some of the most alarming and ignorant things about beavers from Ohio. Remember the trapper that gave a lecture about beavers at the local nature center? When I wrote them that they should bring someone to really talk about beaver benefits his aunt wrote me back and helpfully offered to make a coat from me.  I honestly thought they’d be the very last state in the nation to recognize the value of beaver wetlands.

Until this morning.

Balance of beaver, human needs.

A detention basin along King Street has become an accidental wetland at the paws of furry, semi-aquatic rodents that recently moved into the village.

Beavers have transformed a three-acre stormwater management area on the 45-acre Village-owned Glass Farm into a diverse ecosystem that has attracted great egrets, wood ducks, snapping turtles, cedar waxwings, foxes, green frogs and more.


One of the beavers that have built a dam in a stormwater management area in the Glass Farm. (Submitted photo by Scott Stolsenberg)

 But the beavers have been a menace, too. Over the last few years, Village crews were forced to repeatedly destroy beaver dams blocking a culvert that carries a stream on the property under King Street. The dam-blocked culvert may have worsened flooding on the stream during a five-inch rain event in May.

In a recent truce between castorimorpha and human, the beavers are now allowed to stay, thanks to a contraption proposed by two villagers, designed by a local engineer, built by Village crews and installed this summer.

 The “beaver deceiver” allows local beavers to dam the culvert while allowing some water to still flow through. And while the formerly dry detention basin now has standing water, its ability to prevent flooding downstream has only been slightly reduced.

Someone pinch me, I’m dreaming! Ohio using a beaver deceiver instead of a trap? A fence instead of a back ho? If you told me this was happening I wouldn’t believe you. I’m still not sure I believe it now. Ohio put in a beaver deceiver. I can’t stop shaking my head. Admittedly, they’re still worried about mosquitoes and the engineer who installed it thinks he INVENTED it, but it is a pretty remarkable thing when Ohio decides to protect a culvert because it might benefit wetlands.

Not only were the beavers saved, but other species attracted to the new ecosystem can thrive too, while the wetland will additionally purify the stream, according to Village Council member Marianne MacQueen, who was instrumental in the effort. He said he believes the combination of ecological and educational benefits are worth it, as does MacQueen.

 “Given the destruction we are doing to our environment, to have one little gem of a wetlands in our village that’s providing for a diversity of species is well worth the effort,” MacQueen said. “We spent a couple hundred dollars on a flow device so the beavers can remain, and now the rest of the species can remain too.”

Beaver benefits

In a talk last week on how beavers are “nature’s extraordinary engineers” local biologist Vickie Hennessy explained how beavers are essential to species diversity. About half of all rare and endangered species in the U.S. require wetlands to survive, while the decline of the beaver — and wetlands — have been a major factor in decline of species diversity, she said.

“Beavers are a keystone species because they create an ecosystem other species are dependent upon,” Hennessy said.

That did it. A  talk about beavers? Last week? The description of beaver benefits  is so accurate I had to go look Vickie up. Turns out she teaches at a community college and is the president of the Green Environmental Coalition in Yellow Springs Ohio, which is largely responsible for this thoughtful response to beavers.  The website says GEC is a grass roots organization devoted to clean water, chemical reduction and citizen participation. No kidding. They have a smart looking logo and website and this all shouldn’t surprise us since  Vickie is from Menlo park and went to San Francisco State.

Do you wanna bet she’s heard about the Martinez Beavers?

CaptureShe sure  did an outstanding job of educating the reporter, as well as at least one wildlife photographer.

Nature photographer Scott Stolsenberg, whose Robinwood Drive home backs up to the Glass Farm, has witnessed a transformation on the property in a short amount of time.

 “The whole ecosystem has changed,” Stolsenberg said. “There is a diversity of wildlife because you have trees, fields and water there,” he said, referring to a small stand of trees and active farmland also located on the 14-acre conservation area on the eastern portion of Glass Farm.

 Stolsenberg has seen in the area — and photographed — nesting mallard ducks, foxes hunting, spawning toads and frogs, a catbird dining on a praying mantis, blue herons diving for fish and a variety of birds passing through, including sandpipers, blue herons, great egrets, cedar waxwings, yellow-shafted flickers, sharp-shinned hawks and more.

Wow. This is how it all started. First you get the photographer and a few reporters on your side, and then you change the way a city handles beavers and start teaching other cities to do the same. Great work Vickie!

Beaver Festival Ohio?


Thankful for Beavers

Posted by heidi08 On November - 27 - 2014Comments Off


We all have impossibly many things to do today but I thought Worth A Dam would take a moment to say what we’re thankful for this year, the ninth in which the most famous beaver family in the world has, against all odds, lived to celebrate it’s 20th birth. Since we’ll do a countdown at new years of significant events, I thought today would be limited to JUST things I’m grateful for, that I didn’t expect, and never made happen. If you think of some I forgotten send them email me and I’ll add to the list.

  • Tom Russert recommending us to Loren Cole of ISI and our new fiscal sponsor.
  • Robert Rust’s tail-slapping beaver at the festival.
  • Deidre independently organizing the train trip from Oakland to the festival and Chris Richards doing the lecture for free.
  • New Beaver friends from Napa helping with the festival, including helping Jon lift the heavy stage.
  • Inheriting the stage after NPS retired it.
  • The Environmental Scientist from Phillips 66 contacting me regarding a flow device and staying on the case until it was installed to protect Rodeo’s beavers.
  • Hank and Paula donating a case of wine for the silent auction.
  • The generosity of Etsy craftsmen and women from all over the world donating to the silent auction.
  • Pam from ISI working at the festival in membership and auction.
  • Robin indepently getting a PRA records request on every  depredation permit issued in California, and grimly helping me log them into a massive spread sheet. Three times.
  • My friend Michelle from grad school getting her stats friend to analyze the data for us because he loves beavers!
  • Beavers coming back to 4 Seasons and advocates at the ready protecting them.
  • The Kit coming home to live with both parents again!
  • Beaver benefits in the New York Times at last!

Have a great day with loved ones, and thanks for making miracles happen from all of us at Worth A Dam. Save room for dessert.

From our friend Rusty in Napa:

Friendly Gestures

Posted by heidi08 On November - 25 - 2014Comments Off

Mom, Dad and kit emerged from the bank hole at the lodge last night and heartily enjoyed some willow. Our visitors from Berkeley got the complete audience, thanked us with a donation and headed off to Lemon Grass Bistro for dinner.  I was happy to see the beaver family together and to see the kit back in close quarters with his parents where he belonged.

Apparently, in Napa our beaver friends had a kind of reunion as well. Rusty, Robin and Hank all showed up at the dam at the same time to look for elusive beavers and were treated to a long and rare (in recent weeks) sighting, Apparently this yearling was hungry for willowbark and nothing – I mean NOTHING – else would do. About two thirds in he even climbs up into the tule bank to retrieve another one. I guess we have our answer to the question of beaver memory.

There was also a donation waiting for us when we got back from the beaver dam. This one from an attorney who tried the famous beaver case back in 2000. It was won at the appellate level where he showed that removing beaver from Lake Skinner caused such a dramatic impact that it required a CEQA exemption. The Department and Fish and Game and the Metropolitan Water District got to pay for that trial. Including his fees and the expense of bringing in Donald Hey from Chicago and Sherri Tippie from Colorado. (You can see why this case is popular with me.)  I learned about it when he wrote our mayor way back during the initial bruhaha of 2007. Here’s some of my favorite parts but you should really plan on reading the whole thing.

Lake Skinner1He successfully argued (the court says “albeit over-dramatically”- Hrmph!)  that getting rid of beavers at Lake Skinner was a DISCRETIONARY decision rather than a ministerial one. And therefore subject to CEQA. In addition, he argued that removing beavers from Lake Skinner might even eliminate them from Southern California entirely. Which, if you consider depredation permits as a good indicator of population, it did. See those big white counties at the bottom? Where there were no beaver to kill? Riverside is the long thin straight one that goes across the state.

Ca depredation permitsCan Southern California really afford to eliminate its “water-savers”?