No Roses for Beavers

Beavers Abroad and Abreast

heidi08 Beavers, Beavers elsewhere, City Reports, Environmental, Friends of Martinez Beavers May 30, 2012

If I had to choose a favorite animal it would be the beaver

Nature Talks

Unionleader New Hampshire

IF I HAD TO PICK a favorite animal, the beaver would find itself heading the list. Oh, I know the placement of dams built by these wondrous creatures can upset folks who have different land-use objectives, but I really enjoy their company.

Now that’s the kind of opening paragraph that makes me sigh, settle back in my chair, pick up the coffee and look forward to a good read. Thanks Stacey (who I read is a 90 year- old man and an award winning writer.) Beavers are your favorite? Gosh, I know just what you mean!

Beaver ponds attract many other animals and, with the exception of river otters, beavers appear quite willing to share their pond with them. I came to that conclusion several years ago when the first pair of beavers constructed a dam. They turned our original half-acre “dug” pond into a nearly two- acre body of water. In time, the enlarged pond attracted many species of birds including wild turkeys, grackles, song sparrows, scarlet tanagers, catbirds and several kinds of warblers. These birds built nests among the various shrubs and small trees that grew around the pond’s edge.

Ahh, what a nice observation! It makes me think of the 2008 research by Hilary Cooke and Steve Zack that beaver chewed trees create ideal nesting habitat for migratory and song birds! Of course, even if a fellow wasn’t a crazy research reader and just sat still and WATCHED his eyes would eventually teach them all about the good they do for the ecosystem. Stacey goes on to say that a friend gave him the article about blue herons nesting in flooded dead trees at beaver ponds, and how much he enjoyed it. Honestly, Stacey is a national treasure. Go read the entire article!

Just one problem with Stacey’s writing as far as I can see

Our beaver pond has always attracted both great blue and green herons. As far as I have observed, there are no fish left of any size.

Um…what do you think those all those birds are doing at your pond if there’s no fish? Come to think of it, why did the old beaver have to chase away the otter in the first place if the otter didn’t have really delicious things to eat? Trust me. There are fish in those ponds.

splittail — Green Heron Catches Splittail at Third Dam: Cheryl Reynolds

Also this morning there’s a beaver revisit in the Martinez Patch. Reporter Jim Caroompas wants to know why the beavers are still controversial even after they have not caused problems for 5 years? He says he’s not exactly a fan, but just genuinely wants to know why the beavers are still disliked. Maybe you can go help by posting your thoughts.

This is Martinez, where even aquatic furry critters become lightning rods for politics. But I don’t understand, now that the fears about the beavers bringing floods and doom to downtown have passed, why they are still the target of so much animosity in some. What have they done other than bring us visitors? Created an active creek eco-system that now includes muskrats, turtles, and other denizens? Brought us national publicity?

I can’t imagine whether this is a genuine question. Doesn’t he remember that the beavers attack was waged by some of the most powerful players in the city; wealthy men who still wield massive powers that affect every ‘pocket‘ of Martinez. (And if you’re a local reader, yes that was a pun). Honestly, hasn’t he heard of the applicable Eratosthenes theorem? I thought everyone learned it by heart in grade school.

I believe its latin name is “sorecus loserium.”

Not just for Beavers, anymore.

heidi08 Environmental, New Species March 9, 2011

A friend whose home is along Alhambra Creek above Brown Street sends these photos of his backyard visitors.

Hooded Mergansers in Alhambra Creek: William Mechling

Regular readers of this blog will recognize the showy plumage of Hooded mergansers. This remarkable fish-eating duck nests in tree cavities in the east and comes out here to enjoy shallow waters during the winter. The excellent Cornell birding site tells me that sometimes several females will lay eggs in a single nest and adds

The Hooded Merganser finds its prey underwater by sight. The merganser can actually change the refractive properties of its eyes to enhance its underwater vision.

How cool is that? A bird with water-vision goggles? What does it mean that Hooded Mergansers are in upper Alhambra Creek? It means there are little fish for them to eat, which is always a good sign. it has been documented that our watershed, like most, gets less healthy and robust as it flows down to the mouth. Increased runoff from streets and drains introduce more toxins and pollutants. In fact the location of the beaver dams is historically the least healthy section of the entire creek.

I like to think that the beavers are changing that one pond at a time.

Once upon a time…

heidi08 Beavers elsewhere, City Reports, Environmental, Uncategorized, Who's Killing Beavers Now? February 15, 2011

Once upon a time, not long ago, there were some beavers swimming and chewing happily in the Owens Valley River in southern california. Hardly anyone noticed that their dams created habitat for numerous waterfowl – the felled trees made homes for obligate nesters, and chewing produced coppicing with dense bushy regrowth that migratory and song birds preferred. One tireless audubon advocate noticed that their ponds flooded some cottonwoods which were the homes of these remarkable birds.

That advocate wrote in the Eastern Sierra Newsletter:

It is important that the Los Angeles Department of Water and Power and the California Department of Fish and Game address this critical issue sooner and not later. Audubon members are urged to contact the Inyo County Board of Supervisors, the California Department of Fish and Game in Bishop and the Los Angeles Department of Water and Power in Bishop to urge them to begin controlling beaver numbers along the lower Owens River in the Lone Pine area (and elsewhere in the southern valley?). The threat to the Great Blue Herons due to girdling or drowning of nesting trees is real and will worsen.

It seems Michael Prather’s warning was the ‘shot heard round LA’ – or at least provided an excellent excuse for the reflexive decision to kill beavers. Los Angeles Water & Power was only too happy to dress up their beaver killin’ in a feathered Audubon suit, and decide without debate that the beavers in an entire range should be killed to protect the birds. Never mind that this was all done 10 years ago with disastrous and well documented results.

‘‘Beavers Will Die So Birds Can Survive.’’ This headline ran in the local Riverside, California, newspaper in January 1999 (Farwell 1999a). It marked the beginning of an effort by the management of the Southwestern Riverside County Multi-Species Reserve to eliminate beavers with the purpose of protecting songbird habitat.

concluding

Observations at Lake Skinner produced insufficient data to demonstrate that beavers harmed habitat for either least Bell’s vireo or southwestern willow flycatcher. In general, vegetation ‘‘managed’’ by beavers favors songbirds, both by providing nesting opportunities and boosting insect populations as a food base, some examples of which are summarized by Mu ller-Schwarze and Sun (2003).

Environ Manage (2007) 39:460-471: Management by Assertion: Beavers and Songbirds at Lake Skinner (Riverside County, California)

Travis Longcore , Catherine Rich & Dietland Muller-Schwarze

Alright, maybe beavers are good for little tiny birds, but Mr. Prather was worried about majestic blue herons. What about them? Funny thing, here’s an interesting paper put forward by Fish & Game in New Hampshire. Click on the link to read the highlighted sections which demonstrate the herons often nest in flooded dead trees of beaver ponds, and are in fact dependent on them.

Great Blue Heron (and beaver dependence) Kelly JR New Hampshire Fish and Game

Well, maybe those New England herons are different? How do we know that beavers are good for this specific habitat in this specific waterway? It’s not like there’s an technical study done on this exact location to assess the impact of beavers in Owens valley.

Oh.

Beaver ponds generally provide unique and valuable habitat for many species of wildlife. Increased structural complexity and high interspersion of unique plant communities and habitat features are important factors influencing wildlife species presence and abundance. High breeding bird density, bird species richness and diversity, and total breeding bird biomass are typically associated with beaver ponds.

Well sure, there may be some incidental good that beavers do for an area, but its the conclusion of the report that really matters. I’m sure that the department of water and power wouldn’t have made the decision to kill all the beavers if the report they commissioned had recommended something else.

Although beaver activity has resulted in the removal of much willow and other shrub and woody vegetation and the dams create favorable tule conditions and reduce fish spawning habitat, they also provide important fish rearing habitat, mesic meadows, and promote the growth of other riparian species. It is most likely that the physical removal of beaver dams will result in more adverse environmental impacts than environmental benefits.

It is our conclusion that beaver dams should be left as they are, allow the natural forces associated with future out-of-channel and base flows to remove or incorporate them into the riverine ecosystem, but focus on controlling the number of beaver by reach through trapping as the management strategy.

Wow.

So a commissioned report advised keeping a healthy population of beavers, beaver dams have been proven to benefit birds including the great blue heron, and Mr. Prather is still able to say “eek beaver!” and provide environmental cover for a species genocide campaign that not a single reporter can be bothered to question.

Are we surprised?

(Many thanks to RL for finding the articles that made ashes of the Owens valley beaver killing argument.)