About Me

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Native Californian, biologist, wildlife conservation consultant, retired Smithsonian scientist, father of two daughters, grandfather of 4 small primates. INTJ. Believes nature is infinitely more interesting than shopping malls. Born 100 years too late.

Tuesday, January 27, 2015

Squirrel Creek Campground

The view from the developer's lodge

Squirrel Creek Campground, Alaska -- August 19, 2014

We arrived in late afternoon, took campsite 16, and made the trailer ready for habitation.

While the redhead fed the dog, I made a recce to a large beaver lodge across the lake.

The trail soon petered out, but beaver skids and felled cottonwoods told me I was in a development zone.

It was the kind of development I like to see; so I turned back to fetch 3 cameras.

Again I beelined to the lodge, and found it gloriously covered with mud pies and giving off a strange gamey smell.

If that was the smell of castoreum it wasn't the beaver scent I use.

I set the infra-red video camera at the lodge, and staked the two still cameras at the beaver skids.

And I did a little experiment. I dabbed castoreum on the trail of the less active one.

A sudden splash caught me off guard!  Tail slapping. An insolent beaver was keeping tabs on me.  Three of them were cruising offshore.

Dinner was on the stove when I got back, and I was in my bunk when my wife reported that some men were coming through camp.

Two young guys with backpacks, fishing rods, and a big yellow lab on a length of logging chain traipsed past the trailer with the determination of Lewis and Clark.

They were heading right to my beaver sets.

I poked my head out the door.

"Hey guys!"

The first fellow just kept going.

"I've got several camera traps staked near the shore line."

The guy with the dog turned his head.

"Just want you to know the scent lure may attract the dog, okay?"

He looked at me with a slack-jawed expression, nodded, and was gone.

This was bothersome.

Suspicion and revenge scenarios flooded my thoughts. They passed through camp an hour later.

My suspicion was undeserved. I found my cams the next morning.

The video cam had failed -- a shame, because it looked like
they had a mud fight at the lodge last night.

Disappointment -- moisture on the lens
and wrong camera placement. 

And damn! The skid by the felled cottonwood was another failure; it had 9 blurry pictures of beavers hauling limbs toward the pond.

But the castoreum set came through with 130 photos triggered in 3.5 hours.

Okay, there were no prize winners, but at least the beaver was recognizable as a beaver.

Checking out the scene soon after I left.

Wading through the dew-drenched brush to check those cams was a delight, and the experience visited me with an afterglow during the long drive home.

Responding to the castoreum on the skid late later that evening.

We passed hundreds of beaver works along the Alcan and Cassiar Highways, and almost all of them called -- 'get in your canoe and check me out'.

I decided to spend some time appreciating beaver lodges in the Sierra Nevada when I got home.

Tuesday, January 13, 2015

Return of the Fisher

The football game wasn't going my way; so I decided to get physical and pull 3 cameras that had been soaking in the rain.

I headed up Skyway, parked the truck, mountain-biked a couple miles, surmounted a blow-down across the trail, and fell on my butt on the way down the ravine.

The first camera was dry, but three bears had bumped it off target during a  bumble-fest of scent-rubbing.

The news from the second camera was good and bad.

The bad news was the water in the case; it shorted a circuit and shuttered pictures like a machine gun.

The good news was a photo of a radio-collared fisher.

And the camera in the next ravine had more pictures of the same critter.

Discovering the scent lure
A good thing has happened.

California Department of Fish and Wildlife, the US Fish and Wildlife Service, and Sierra Pacific Industries (SPI) have joined forces to restore the fisher to the northern Sierra Nevada.

This radio-collared animal might be one of 40 fishers that were translocated from the northwest corner of the state to SPI land near Stirling City.

But it could also be one of the 48 offspring born to the colonizers over the past three years.

The historical occurrence of fisher in California has been a puzzle.

California's great academic naturalist, Joseph Grinnell, assumed fishers ranged throughout the Sierra Nevada.

Since Grinnell's time however, fishers were found to be missing from a 420 km section of the northern Sierra Nevada.

This "dead zone" is an enigma, because the habitat seems to have everything a fisher needs . . . a fisher-friendly climate, lots of trees, water, cover, squirrels, and maybe even a few porcupine.

Biologists have assumed that logging and trapping divided the population, leaving one in the southern Sierra Nevada and the other in the Trinity Alps and coastal mountains of NW California.

A recent study based on DNA from museum specimens and living animals tells a different story.

California's fishers became divided populations about 1000 years ago.

In other words, we can't blame the fisher gap on the Spanish colonization of California and the gold-lust-mayhem of the 49ers.

Fur trapping and intensive logging in the early 1900s, however, caused the continued decline of fishers across North America, and in 1946 California was the last fisher range state to enact protective legislation.

The two populations are now genetically different, which raises questions about their conservation.

Like, should we connect the northern and southern populations, and risk genetic pollution of their gene pools?

Or should we colonize the gap with fishers and brace the population against future environmental unknowns?

I rather like the idea of filling the fisher gap. California's just an experiment, isn't it?

Having a few more fishers around makes the place more interesting.


Grinnell, J. 1913. A distributional list of the mammals of California. Proceedings of the California Academy of Sciences, 3:265-390

Grinnell J, Dixon JS, Linsdale JM (1937) Fur-bearing mammals of California: their natural history, systematic status, and relations to man. University of California Press, Berkeley. 375 p.

Powell, RA. 1993. The Fisher, life history, ecology and behavior. University of Minnesota Press, Minneapolis. 237 pp.

Powell, RA,  RC Swiers, AN Facka, S Matthews, and D Clifford. 2013.  Reintroduction of Fishers into the Northern Sierra Nevada of California,  Annual Report for 2013 For the period of October 2009 to December 2013, 35 pp. 

Tucker, JM, MK Schwartz, RL Truex, KL Pilgrim, and FW Allendorf. 2014. Historical and Contemporary DNA Indicate Fisher Decline and Isolation Occurred Prior to the European Settlement of California. PLOS One 7(12):1-13


Gabriel, MW,  et al. 2014.  Anticoagulant Rodenticides on our Public and Community Lands: Spatial Distribution of Exposure and Poisoning of a Rare Forest Carnivore. PLOS One 7(7): e40163. doi:10.1371/journal.pone.0040163

Zielinski WJ, Kucera TE, Barrett RH (1995) Current distribution of the fisher,

Martes pennanti, in California. Calif Fish Game 81: 104–112.