Wayne and Tweeters,

One might speculate that a lot of the concern for Pileated comes from
low numbers and habitat loss.

Northern Flickers decreasing in Washington State? Not according to
the Christmas Bird Count Data. http://audubon2.org/cbchist/table.html
The British Columbia Christmas Bird count data also indicates
significant Northern Flicker increases in the last twenty years.

Larry Schwitters
Issaquah

On Dec 7, 2010, at 10:36 AM, Wayne Weber wrote:

> Tweeters,
>
> I would like to add my comments on the list of Washington ?State
> Candidate? species listed by Scott Downes and commented on by Gene
> Hunn.
>
> First of all: the Pileated Woodpecker, in my professional opinion,
> has absolutely no business being on such a list. I cite as evidence
> data from Breeding Bird Survey population trends, as shown on the
> BBS website (http://www.mbr-pwrc.usgs.gov/bbs/specl07.html ) .
> For Washington, a quick glance at the data might suggest that
> concern is warranted; the table indicates an average decline in WA
> of 3.1% per year (1966 to 2007). However, this trend is based on
> very low numbers (about 0.5 woodpeckers per BBS route), and is NOT
> statistically significant. Moreover, the population trend in the
> last 30 years (1980 to 2007) is positive, with an increase of 1.7%
> per year; this is offset by an apparent decrease in the early years
> of the BBS.
>
> More important, however, are population trends in areas adjacent to
> Washington. Both BC and Oregon show a long-term INCREASING trend:
> 3.1% per year in BC, and 1.6% per year in Oregon. This trend is
> statistically significant in BC, although not in Oregon.
>
> Furthermore, looking at the trends for other states, provinces, and
> regions, many of them show statistically significant increases, and
> NOT ONE OF THEM shows a statistically significant decrease. For all
> of North America (USA and Canada combined), Pileated Woodpeckers
> show an average increase of 1.8% per year, which is highly
> significant statistically.
>
> In short: the Washington trend for Pileated Woodpecker appears to
> be a spurious trend based on a small sample size in the early years
> of the BBS. Pileated Woodpecker is a species which is INCREASING
> everywhere, not decreasing. We should be more concerned about
> Northern Flickers, which although still commoner than Pileateds,
> show significant DECREASING trends in many areas.
>
> As for the other species mentioned by Scott as ?State Candidate?
> species-- nearly all of them are on similar lists in adjacent
> provinces and states, based on known population declines or habitat
> losses. The sole exception may be Black-backed Woodpecker, which is
> too scarce in the Northwest to be reliably sampled by the BBS. Key
> habitat for this species is forests killed by wildfires or insect
> outbreaks, and populations are somewhat cyclic depending on
> availability of habitat, but I don?t think there is evidence of a
> long-term decline.
>
> All of the other species (besides the two above) listed by Scott
> have some kind of special status in BC-- either listed federally in
> Canada as endangered or threatened, or blue-listed in BC, which is
> the equivalent of ?special concern? status. (The exceptions are
> Loggerhead Shrike and Sage Sparrow, which do not breed in BC.) The
> latter status applies to Flammulated Owl, which has definitely lost
> some habitat because of logging of old-growth Douglas-fir forests,
> but is in better shape in both BC and Washington than the
> beleaguered Spotted Owl.
>
>
> Population trends from the BBS are important data which should
> always be considered in determining whether a species deserves some
> kind of special conservation status, although some bird species are
> too scarce within the area of concern, or have too specialized a
> habitat, for BBS trends too be meaningful. It appears that the
> people who put the Pileated Woodpecker on the ?State Candidate? list
> in WA either overlooked or misinterpreted the BBS data for that
> species.
>
> Wayne C. Weber
> Delta, BC
> contopus at telus.net
> (Retired biologist, BC Ministry of Environment)
>
>


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