"Steppie" wrote:

>I've always gotten the impression Black-backed Woodpeckers are
>quintessential nomads. I believe a part of the population is always on the
>move through eastside forests seeking diseased or recently burned stands of
>timber. Their habitat is from the upper ponderosa pine up to the subalpine
>zone, with most in the mixed-conifer forests. Because of this nomadism, once
>a food bonanza is found - either diseased or burnt stands - their numbers
>may gradually build in this area. As the food source diminishes in these
>area of optimum foraging, individuals resume their wanderings( this bird
>would perhaps better be named Picoides peregrinus rather than articus as the
>Three-toed Woodpecker is more "arctic" than Black-backed). In a burn, the
>explosion of bark and other beetles seems to peak within a year after the
>fire and then numbers of these insects diminish. By the third or fourth year
>after the fire, there may be relatively few of the types of insects which
>this woodpecker is after. So, typically, after that number of years
>post-fire, the Black-backs have moved on; Hairy and Three-toed Woodpeckers
>do not seem to show such pronounced wandering tendencies.

I would think this is a function of the Black-backed's preferred prey species or
foraging method. I await the Birds of North America accounts of the two 3-toed
species with much interest. The Three-toed's range does not extend all that much
farther north than the Black-backed's, actually.

>So, I would not expect strong nest site fidelity in Black-backs, but perhaps
>more in Three-toed Woodpeckers. At the nest site, they are probably no more
>shy than most of our other birds of the forests, nor subject to disturbance.

Perhaps Three-toeds wander about as much as Black-backeds but their greater
numbers lead to the impression of site fidelity??? Either way, Black-backeds are
by far the rarest of the regularly-occurring woodpeckers in this part of central
BC (if I were to rank descending abundance of my local woodpeckers in the
summer, it would be something like Flicker, Hairy, Sapsuckers, Three-toed,
Pileated, Downy and Black-backed. Pileated and Three-toed are likely just about
equal although Pileated are seen much more often due to their higher
visibility).

>Overall, for Black-backs, their long-term outlook in eastside forests must
>be grim. The core of their distribution is in forests with high economic
>value and outside wilderness areas. The timber industry aims to remove
>diseased and burned trees quickly. For example, much grand fir in
>south-central WA is infected by a root rot. Many millions of board feet of
>diseased grand fir (and eastside Spotted Owl habitat) has been lost in the
>last 10-15 years from Snoqualmie Pass thtrough the Cascades to Oregon). This
>has not been good for either woodpecker or owls - and the rest of the
>ecosystem.

Yes, "diseased" and or "bug-killed" trees have become the latest excuse to allow
timber extraction in areas otherwise set-aside in BC, too.

- Jack Bowling
Prince George, BC
jcbowling at mindlink.bc.ca

P.S. Please excuse my multiple postings of yesterday. I screwed up the date on
the first one (experimenting with a new mailer) and re-sent it. Turned out it
had gone out anyway.