Flow Devices - A step toward co-existence

Beavers are triggered to work on the dam by the sound of running water. Flow devices are used to trick or prevent the beaver from building it up.

Beaver management expert Skip Lisle (shown here) installed a flow regulating device on the primary dam. He refers to this device as a “Castor Master”.

Basically, it is double walled, 10-inch flexible tubing that extends on both sides of the dam to allow water to flow through based on gravity. (There is no suction or mechanical parts).

The entrance to the tubing is protected by wire mesh Skip calls the “filter”. This is wide enough to prevent the beavers from feeling the suction and blocking theflow. A schematic drawing (below) of the similar “Flexible Leveler” is shown from Beaver management expert Mike Callahan, and outlines what is involved.

The beavers are prevented from obstructing the pipe, and the pipe is installed to keep the water at the desired height. Although there has been some confusion about the filter’s purpose it is not a cage for the beavers,but more like a cage for the pipe. The exit from the pipe is securely anchored with rebar because of the heavy tides.

Skip Lisle installed this device in early January 08 and the height of the dam has been safely maintained since that time. This is one of the many efforts that have been made toward co-existing. It goes to show you what a little creative problem solving can accomplish.

Wire Wrapping: Cheap, Easy, and beaver friendly.

One of the most notorious conflicts between humans and beavers is horticultural: humans plant trees and beavers take them. Beavers eat leaves and the inside layer of bark, and use remaining wood for lodge and dam building. This causes considerable friction, and in many places beavers are eliminated simply because of the damage of tree removal. This is an unnecessary solution to a problem that is easily and cheaply solved. I wrote the city nearly a year ago about the recommendations of the Haw River Assembly http://www.hawriver.org/index.php?contentid=38 for wire wrapping of trees.

In a fantastic article entitled “Peaceful coexistence with Beavers” Kim Willis writes “Protect individual trees by wrapping them with heavy wire fencing 2” x 4” in size and 3 feet high. The fencing should be placed 6 to 12 inches from the tree so that the beavers can’t get their teeth on the tree. The fencing needs to be rugged enough to withstand forty or so pounds of hungry beaver flesh pressing on it. In addition, you need to anchor the wire fencing to the ground to prevent the beavers from crawling under.”

Here in Martinez the trees between Ward and Green street have been wrapped since October, and some trees between Main and Escobar are now wrapped as well. Dr. Bruce Baker, who wrote the chapter on beavers in Feldhamer’s “Wild Mammals of North America”, wrote me about an alternate technique of painting the trees with bark-colored sand, since beavers do not like the feeling of grit in their teeth. Despite these readily available and simple solutions, beaver-phobes tend towards the extreme response:

Just recently the city of Bakersfield made a determination to remove beavers based on tree felling. I wrote the following letter which was responded to in this editorial. http://people.bakersfield.com/home/Blog/editorials/18979

As a member of the Martinez,CA subcommittee on beaver management I wanted to respond to your article regarding concerns of beavers taking trees near the bike path. Although the article didn’t specifically mention extermination/depredation, this will most likely be the solution offered by DFG, which doesn’t allow relocation of beavers. Why not take advice from the real experts and address the issue of tree cutting directly? Trees are easily wire-wrapped to prevent cutting, and specifications for successful protection are readily available. Perhaps the city of Bakersfield should review the appelate decision on Friends of Lake Skinner vs. the Department of Fish and Game et al, which found that killing beavers in response to tree removal was a discretionary action that required an Environmental Impact Report to meet the standards of CEQA. This turned out to be an expensive and long battle for the city which they ultimately lost. Beavers improve habitat, encourage other species, and change their environment for the better.

Smart cities learn to see the forest for the trees….

Killing beavers to protect trees is the equivalent of impounding cars to stop traffic accidents. Yes, it works but at what cost? The obvious solution is to install a “traffic lights” that can regulate use. We determine where the beavers are allowed to feed, protect the trees we can’t live without, and enforce commonsense rules for ongoing safe use of the “road”.

So yesterday I had a chance to meet with new beaver-friend Brock Dolman and walk him around the dams. He had fascinating questions and things to say about the flora and fauna in the area. One thing that has him particularly motivated at the moment is the reintroduction project for beavers in the Russian River Area. He would like to work with the salmon people to spread the news about beavers helping salmon, and use that as a foothold to get them viewed in a different way. Potential rather than Pest.

He obviously didn’t have to do much convincing with me!

Still, I wanted to make sure to show him the flow device and talk about its value, because after three years of following these stories, it is clear to me that the future of beavers is inextricably tied to the future of flow devices and culvert fences. People are going to complain and worry about water height. They are going to get upset about road flooding. Even if the salmon personally swam onto their doorstep, there will be no way to convince them to keep beavers without some proven management tools. The techniques may be out there, but having someone knowledgeable implement them makes the difference between a device that works and pays for itself many times over, and a failed installation that allows beaver-foes to say pedantically “those things never work”. (See Mary Tappel and the Entire Department of CA Fish & Game!)

So where are the professional installers? Well first and foremost is Skip Lisle of Vermont. He is the inventor of the “beaver deceiver” and learned his trade back with the Penobscot Nation where he discovered that beavers dislike trapezoidal shapes and won’t build dams against fences in that shape. Skip travels around the country and around the world doing installs, and training. He installed our successful flow device which will be 2 years old on Saturday.

In the late 90’s, Mike and Ruth Callahan attended a Humane Society workshop on beavers and formed the Pioneer Valley Wetland Volunteers. Mike trained with Skip Lisle and learned the ropes, gradually building a great demand for his skills around the State of Massachusetts. Eventually he quit the day job and started the business of Beaver Solutions. Mike Feels strongly that the best way to increase the beaver population is to teach more people about successful beaver management. He received an AWI grant last year to do just that. His DVD will be launched in the Spring.

Jake Jacobsen is the watershed steward for Stillaquamish county in Washington State. He teaches local property owners in his jurisdiction the ins and outs of beaver management. He also works with several non-profits around the area to teach the installation of flow devices and culvert blockers. In his spare time (?) Jake manages his own, international nonprofit, dedicated to protecting watersheds. Meanwhile, the savvy Washington state also boasts The Lands Council, with not one but two Vista Corp trainees learning the skills of beaver management. They are responsible for the Beaver solution video, and boast the very best beaver site on the web. (sniff)

Mary O’Brien is the Utah Forests Manager for the Grand Canyon Trust.  She was the powerhouse behind the “Working Beaver Conference” and a major force for beaver advocacy in Utah. Remember, Utah’s State Department of Wildlife is introducing a state wide beaver management program this year, so they know their flow devices.

Ned Bruha (AKA: The Skunk Whisperer) is a rockstar of wildlife rescue out in Oklahoma where he uses humane methods to manage all kinds of wildlife problems. Ned has been particularly interested in communicating with Worth A Dam about beavers, and we recently put him in touch with Mike Callahan to get some flow device pointers.

Sharon & Owen Brown, of Beavers Wetlands & Wildlife, are trustees of the beaver sanctuary bequeathed by famous advocate Dorothy Richards in New York State. They are connected to all the beaver developments around the nation and are a wealth of information about flow devices and their installation.

Sarah Summerville is the trustee of the Unexpected Wildlife Refuge in New Jersey, which is the inherited organization and lands of well know beaver advocate Hope Sawyer Buyukmihci. Sarah is a great beaver friend herself and has learned a thing or two about flow devices.

Last but certainly not least, Skip Hilliker is a former trapper and new found beaver management advocate in Connecticut. He is an employee of the Humane Society for that state, and spends the year doing beaver installations.

Okay, that should be a basic introduction. Here’s some footage to give you the idea.

Martinez Beavers and Hydrology

Subcommittee member Igor Skaredoff summarizes the hydrology section of the report here for the website. In case you don’t already know, his name is synonymous with the stewardship of Alhambra Creek and he has been long honored for his tireless work and dedicated community spirit. Having watched him at close quarters these past three months, I would add praise for a cooperative and diplomatic personal style that allows him to find friends where others would only find argument. He writes:

The Martinez Beaver Committee’s report to the City Council contains a proposed solution to the Beaver coexistence/Flood protection issue.

This proposal leaves the dam in place and controls its height. It also provides some low (2ft tall) “seating walls” to fill in the gaps in the existing structures that help protect against flooding. Additionally, the proposal improves drainage at the Castro/Marina Vista intersection to allow a controlled overland flow to re-enter the Creek north of the Marina Vista Bridge. The floodplain would also be expanded in the section of Creek between the Escobar and Marina Street Bridges by excavating a terrace.

Taken together, these measures would provide flood protection that is equivalent or better when compared with the “pre-beaver” situation.

Additional enhancements, such as interpretive signs, habitat improvement by planting California Native Plants and enhancing the educational improvements are also included.

Several local and county groups and agencies are prepared to partner with the City to develop, execute and steward this project, and to help write grant applications for funding to supplement the City’s investment.

This proposal offers a way for the Martinez community to coexist with the beavers while protecting itself from flooding. The opportunities offered by successful coexistence for stimulating downtown visitation and enhancing education and habitat are also part of the proposal.

The proposed flood protection improvements are shown in the illustration below. For more detail, see the complete report available elsewhere on this webpage.

Igor Skaredoff

Thanks Igor for your hard work on this report and your calming influence on our beaver-passionate spirits!

Heidi P. Perryman, Ph.D.

Our Wildlife VP, Cheryl Reynolds, sent this article which I read with hand-rubbing delight. The words Bwahaha may have even escaped my lips, so closely did the article follow my own designs. I’ll give you a gist, but you might want to go read the whole thing.

State officials expect that climate change will create some profound water supply problems in eastern Washington.  But there’s a potential solution that’s not only cheap, but also cute and furry: beavers.

Ahhhhh the sweet music of recognition. Wait, I need some popcorn and a tissue. Okay, go ahead.

Here’s the problem:  according to climate scientists, warmer temperatures are already melting mountain snows earlier in the spring.  That leaves streams and rivers short on water in mid-summer, just when salmon, farms, and homes really need it.  Scientists expect that, as winter temperatures in the Northwest rise, the state’s summertime water shortages will only get worse.  (The preamble in this state Executive Order has a nice, succinct rundown of the impacts of climate change that the state has already experienced.)

Okay so climate change is a’comin and we need little dams implemented to hold our water in streams so that we can eek it out after the rains and not waste it all in runoff to the sea. I guess that makes sense.

That might sound pretty reasonable, except for a few niggling details – like that fact that the dams would likely cost Washington taxpayers billions of dollars, while flooding thousands of acres of farmland and wildlife habitat.

Hmmm, let me think. What is the cheapest way to build and maintain little dams along the watershed? Gosh, if only there were some way to use materials already in the area and not have to transport them. It could be tricky to get started, you might have the repair crew actually on site 24/7 to make sure it operates the way its supposed to. They may have to try over and over to get the structure of the dams just right in the beginning. And our state is broke, so they’re going to have to work for practically nothing. Where are you going to find a construction company like that?

The Lands Council, a Spokane based non-profit, thinks that it has a better idea:  enhance beaver populations, and let the furry wonders do the dam construction for free!

Ohhhh my goodness. Check out the schedule for the “Working Beavers Forum” conference at the end of the month. I could almost cry. No wait, I am crying. Our friend Sherri Tippie will be there talking about relocation, along with a host of amazing others. What I wouldn’t give to be a fly on the wall.

Interestingly, our beaver friend from New Zealand just started the exact same conversation with his local magistrate who is planning on charging taxpayers to build a little series of dams to deal with their drought conditions. For the record, there are no beaver in New Zealand, but plenty of willow. I’ll keep you posted how that develops.

Photo:Cheryl Reynolds

Our own Skip Lisle sends this recent article on the anxiety provoking issue of beaver digging. His central argument focuses on the demonstrable fact that beavers don’t actually waste their time or energy. Rather than riddling a bank with holes, they dig according to the most economic, practical concerns. He emphasizes sense over sensationalism, and outlines the best way to mitigate this behavior. (Hint: the answer doesn’t involve sheetpile) Go read the article, but maybe this will whet your whistle:

Largely instinct-driven, beaver behavior is usually efficient and logical, and rarely counter-productive. Digging in banks is not done randomly or compulsively, but to make tunnels and dens as protection from predators and the elements. Although this activity can pose a serious threat to property, the danger is often exaggerated. Perhaps, because these burrows are underground and invisible, it is easy for one’s imagination to conjure up a subterranean world riddled like Swiss cheese. In reality, tunnels and burrows are not dense, deep, complex, or interconnected systems. They are usually isolated from one another, simple, and shallow.

I would put the entire pithy treatise on the blog for you to read, but Skip has asked me to reference only the PDF so that he can keep minimal control of his writing. Go read it all the way through.  It is short and concise, tells it like it is,  and in my books deserves very high praise since it references the much bandied-about-term “swiss cheese” without being at all sarcastic.

For the record, beaver tunnels do not look anything like this.

Check out this article from Juneau about the volunteer group intervening to keep beavers from causing problems on the hiking trails at Dredge lake. The original plan was apparently every institution’s original plan but residents didn’t want the beavers killed. An alternative solution was suggested involving wrapping some trees and unplugging culverts. The success has helped form cooperation between Rangers and volunteers, and at this point there is a somewhat stable situation.

The spokesperson for the group, Bob Armstrong, is even publishing a book on the Mendenhall glaciar beavers soon. Like our own Cheryl Reynolds he is an avid birder and wildlife photographer, who found out more about beavers as he worked on this project. Did he happen to read the article on beaver dams increasing songbirds? Or the newer research on beaver dams increasing safe habitat for salmonids? If you get in touch with us Bob, we will load you up with research and problem solving tools.

The biggest one it sounds like you need is the beaver deceiver, and we can put you in touch with its inventor, Skip Lisle. Blocking culverts is a big beaver hazzard, although its been a non-event in Martinez so far. Beavers block where the water goes through because its the easiest. However, they like to build their dams at right angles and are off put by the trapezoidal wire fence Skip installs outside them. You don’t have to dig every night, there is an easier way.

You may also need a flow device or two to control the height of the dams. There are a couple different kinds that accommodate fish easily. You can find plans here or check in with Mike Callahan at Beaver Solutions whose working on making this a more broadly teachable skill.

We entirely applaud your effort and would be thrilled to offer help in any way possible. A few points in the article gave us pause though,

Beaver lodges at Moose, Crystal and Dredge Lakes appear to have the right level of water-not too high to flood beaver sleeping quarters, not too low to prevent them from reaching their winter food supply.

Obviously beavers don’t want to flood their sleeping quarters either. So either they stop building when the water gets too high, or they move to someplace higher or build upwards. The water height outside the lodge is the same as the height inside the lodge, and sometimes people forget that beavers have this built in reminder of level-setting.

Finally, I twitched a little at this sentence:

All dams are open enough to allow fish passage and avoid flooding.

Sigh. Do what you must to control flooding, but don’t say you are lowering dams to help the fish. Mr. Armstrong you have your work cut out for you educating an entire fish and wildlife department about the role that beaver dams play in making still pools for juvenile salmonids, especially in winter! I would direct you to our friends at the Oregon Department of Fish and Wildlife,  but there’s tons more where that came from. Remember that beaver and salmon co-evolved, long before rangers were there to help lower those dams. Trust me, those fish will work it out.

One of the most exciting parts of watching our beavers in Alhambra Creek is seeing the introduction of the new wildlife they have drawn to the area. Whether its mink or woodpecker or the frog chorus we are expecting back next month, seeing the connections that beavers make in the habitat is rewarding and reminds us how much of our wildlife is interwoven.

But the connections don’t stop there.

Case in point? Let’s talk about Juneau. Our VP of wildlife Cheryl Reynolds sent me an article a couple of weeks ago about beavers near the mendenhall glacier and a volunteer group trying to manage them. I tracked down the spokesperson, Bob Armstrong,  through the wonders of the internet, and started a dialogue. He was primarily interested in how to (a) keep beavers (b) manage culverts and (c) still allow passage of fairly large coho salmon.

Here’s some connections for you.

Back when Sharon Brown of Beavers Wetlands and Wildlife wrote about the Martinez Beavers in her newsletter, beaver fan William Hughes Gaines of New Zealand got interested and we started writing. He was especially interested in salmon, and actually toured all the salmon fisheries along the Canadian coast this summer. I sent Bob’s questions to William and he wrote back some very sound advice and suggested they document the salmon activity with volunteer effort to verify first that there is a problem. He’s interested in that documentation because he’s working on another project with the beavers being reintroduced in Scotland, where they have been gripping their fainting couches over worries that beaver dams will ruin their fishing industry. I also sent Bob’s email to Skip Lisle and Mike Callahan so they could weigh in on salmon solutions.

This single example of “beaver connections” across three continents might end up helping the Juneau beavers, the Scotland beavers, and the general research linking beavers and salmon. When I can’t be at the dam site watching the story unfold, this is another dynamic place to be.

Need more connections? Worth A Dam joined the Nature Blog Network earlier in the week under category of “mammals” and I think this lead to our inclusion here and a host of new visitors. It’s all about making connections.

If Skip or Mike win an all expense paid vacation to Juneau, does Worth A Dam get a finders fee?

Regular readers of this blog will remember our beaver friend in Massachusetts, Mike Callahan.

Back in the murky grip of winter, when Californians were waiting for the temperature to drop and East Coasters were trying to remember what the earth looked like under its white blanket, beaver friend Mike Callahan of Beaver Solutions in Massachusetts was hatching a plan. He wondered about making a series of DVD’s to train willing people to do sensible beaver management. His idea was to create something accessible and hands-on enough to be used by public works crews and maintenance workers across the nation.

Mike talked with the Humane Society and Audubon who were very excited about the project and directed him to apply for the AWI Christine Stevens Grant. Which he did, arguing convincingly that teaching cities to take care of beavers would take care of waterfowl, take care of amphibians, take care of muskrats and minks and otters and improve water quality.

He applied and found out this summer that he was awarded a $10,000 grant for the production. He hired Pinehurst Pictures and Sound to  handle the project. A videographer and good friend is shooting the footage. They’ve been filming installs with the fall colors as a backdrop. As the water gets colder and more uninviting, he’s starting to think about next steps.

Target audience, segment length, teaching emphasis, marketing, outreach, spreading the word. These are things that Worth A Dam has done fairly well, so he asked for our input on the process. Beaver people (and I assume wildlife workers in general) can sometimes be so focused on the important work they do that it’s hard to think about media or outreach. Having stalked the wisest of beaver minds persistently for the past two years, I can honestly say that these wizards are not even great about talking to each other, let alone the rest of the non-believing world. Partly its because they are modest, generally private people, who don’t spend hours bragging about what they do. (You’ll note, for instance, that there are no beaver-management bloggers.) But what good is a brilliant  instructional DVD if no one sees it? If a tree falls in the forest and no one chews it, does it still taste delicious? A project that could save thousands of beavers is worth selling with some great publicity, I’m thinking.

Since Mike’s a huge Patriots fan, I’ll use football lingo. Go Long!

I’m still thinking and mulling, but I gave him two basic ideas. The first is to watch for the next local public beaver issue that hits the media. These things happen all the time, especially in “help-we-can’t-use-cruel-inhumane-traps-and-we’re-surrounded-by-beavers” Massachusetts. (Not that they actually have more beavers, mind you, but they want people to THINK they do. With all that professional hand-wringing Fish and Wildlife have made some good friends in the media, but I digress). So thank the beaver-harrassers for working so hard to create sustaining contacts with the media and then use that visibility to walk heroically on the scene, volunteer to train public works or the highway workers or whoever and do 10 hours for free provided you can film it. Then you have the media relationship already started and you can use that momentum to highlight the DVD series which will be available soon and can teach any city/utilities to handle this problem!

The second thing I’d do is make a “postcard” announcing the DVD. I’d probably do this twice, once for the “this is coming” and the second for “its here”. Send the postcard to the directors of every department of public works, parks and recreation, state park, regional park, highway management, railroad division etc in your state. Seem daunting? It’s not impossible. There are 377 municipalities in Massachusetts. 5 minutes on the web can look up contact information for any one of those cities. 10 people working on this for three hours each will generate all the addresses you need (5 x 377= 31hours). Most directors will have email addresses listed so you can do the whole postcard “virtually”, generate a spreadsheet of the contacts, mail off your postcard with a single click,  and it will cost you nothing but time. Honestly I’d like it sent to every director of public works in each city in the country, but we’re going to need massive worth a dam volunteers to help look up all those addresses.

I had other suggestions…like extra footage about a variety of installs, a 15 minute segment on “why bother” discussing the benefits to the habitat, a short intro or trailer produced and released on youtube to send out with his mailing, a bullet point review at the end of each section, and of course, an outtakes reel for my personal enjoyment.

I’m thinking that my suggestions were a little overwhelming, but I’m pretty sure they’d help, and I’m even more certain its worth investing time and money in. I’m betting there’s a data base somewhere of directors of public works for the state of california…or the nation. Maybe it will just arrive mysteriously in my email one day. You never know, stranger things could happen.

Oh, one final thing Mike asked if I could help with? “Do I have any footage of beavers or creek animals that he could use for the natural history section?”

hahahahahahahaha.

Me? Beaver footage? If I can find anything else on my computer its a holy miracle.

Fans of the Martinez Beavers will understand more intimately than most that the survival of our beavers ultimately depended on just one thing. Sure public outcry made a difference, and fear of political ruin quivered the hearts of at least two on the council, but if the dam had stayed at its original height and continued to pose a flooding threat, they would have been soundly dispatched. (Sent in a pickup truck to Plumas county if the god’s were kind or off to a glue factory somewhere if they were not.)

What fundamentally allowed the beavers to remain with us was the flow device, installed by Skip Lisle and often mistakenly called a “beaver deceiver”. (It’s actually a “Castor Master”.) This allowed for the water height to be lowered in such a way that the movement is disguised from the beavers. They don’t feel the suction and don’t associate the outflow with their dam, so they tolerate the water loss. Skip invented the beaver deceiver during his work with the Penobscot Nation. He went on to develop his ideas for the flow device and round fence over time. Skip is committed to showing the world that flow devices work. He traveled to Lithuania this summer to talk at the conference there, and he is headed for Oregon next week to give a four hour teaching at the State of the Beaver Conference.

Mike Callahan of Beaver Solutions trained with Skip and eventually developed his own full time business around beaver management. His vision of the best use of management skills included a teaching DVD that would allow property owners, cities and transit workers to cheaply implement tools that could manage problematic beaver behavior. He is well aware that allowing this keystone species to remain takes care of so many others, but Mike is a pragmatic beaver defender who helps businesses focus on the bottom line. Installing a successful flow device, he argues, can manage the problem now and in the future. Hiring a trapper is a temporary solution that will get more expensive over time.

Mike was awarded a grant from the AWI last year to make the DVD, and has been working towards its release. Expect it in the Spring of 2010. Recently he approached me asking to pay to include three minutes of my beaver footage in the production. Since Mike’s smart website was the first place I turned with beaver questions LO these many moons ago, and we became friends over the ensuing years, I can’t think of anything more “full circle” than using that footage to help him and help beavers around the country for years to come.  Whatever financial agreement we figure out will go to Worth A Dam.

In the mean time, I am helping him spread the word about the upcoming project with an announcement postcard sent to beaver supporters and interested media. You might recognize my favorite photo from Bob Armstrong of the Mendenhall Glacier Beavers. (He gave his blessing on the prospect, and arranged for Mike to come do a beaver management plan in the state park there.) The idea is to follow up with a second announcement once the project is released. I’m hopeful that by helping more people learn that there are reasonable ways to manage beaver behavior, and inexpensive tools for learning about them,  we can significantly impact the well-being of beavers all around the country.

In the mean time, our wikipedia friend is supposed to be honing a “flow device” entry this weekend. It’s hard to remember so long ago, but in 2007 I definitely had to hunt to find out about options. Remember how many people talked about the Clemson Pond Leveler at the meeting? Someone from Lafayette even donated the funds for one. That was one tool that had been published and talked about, but the technology had already come a long way since then. Mike was the one who explained that to me. Let’s hope “flow device” becomes a household name - at least as common as “snare”.