Phil and Tweeters,

Spruce Grouse are not included in Breeding Bird Survey trend analyses
because they are so rarely recorded that meaningful population trend
data cannot be calculated. This is true not only for Washington, but also
for B.C., and even at the continental level. In Washington, I suspect
that there are only one or two BBS routes, if any, that have ever recorded
Spruce Grouse.

The simple fact is that most of the breeding range of Spruce Grouse is
too far north (or at too high altitudes) to be adequately sampled by
the North American road network.

There are many bird species (examples: Yellow-billed Loon, Black-bellied
Plover, Sanderling, Hoary Redpoll, Harris's Sparrow) for which the BBS
cannot be used to determine population trends, because there is little or
no overlap between their breeding ranges and the area covered by the BBS.
The BBS is also of little if any value in tracking population changes of
colonial waterbirds, rare and localized species, and nocturnal species.
For the scores of bird species that fall into these categories, other
methods must be used to track population changes.


Wayne C. Weber
Delta, BC
contopus at telus.net




----- Original Message -----
From: <vogelfreund at comcast.net>
To: <Tweeters at u.washington.edu>
Sent: Tuesday, July 25, 2006 10:03 PM
Subject: [Tweeters] Spruce Grouse not in BBS?


=====================
7/25/06

To no one in particular:

I'd like to know why Spruce Grouse is left out of the Breeding Bird Surveys.
I almost flunked statistics in college, and tend to gloss over such results.
But I like to look for presence or absence of selected species. And the
ghostly presence of Spruce Grouse (=Franklin's Grouse) in the Cascade Mts.
of the Canadian border region would interest me, if it were available.

Phil Hotlen
Bellingham, WA
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