Dear Tweeters,

Mike Patterson replied to Yvonne Bombardier about Northwestern Crows:

>For many of us here in the Pacific Northwest, the matter was settle by
>David Johnston in _the Biosystematics of American Crows_ (1961).
>Northwestern Crow is probably not a legitimate species (I expect a
>firestorm of flamage from over protective listers who can abide the
>thought of a lost tick).
>
>But, if we assume that Northwestern Crow does exist, there are NO RELIABLE
>FIELD MARKS for sorting them from "Western" Crow (_Corvis brachyrhynchos
>hesperis_). This is especially true at this time of year when many young
>hesperis-type crows are out and about. Size will not get you there. Call
>will not get you there. Jizzy things like flight and "beach foraging
>behaviors" won't get you there.

I, too, am very interested in this problem, and I'm respectively
skeptical about this answer and analysis.

I have been watching and listening closely to north Olympic Peninsula
crows this spring and summer, particularly to their voices, and I believe
that there are two voice morphs of crows around here. Whether they are
distinct species, I don't know, but the differences are commonly clear.

I have made several visits to Salt Creek campground near Joyce this
summer (about 15 miles west of Port Angeles), where many resident crows
frequent the campground, coastal forests, and rocky intertidal (classic
northwestern coastal habitats). The crows at Salt Creek clearly appear
smaller-bodied and have a distinctive lower, throatier call than American
Crows I have known elsewhere. This is also true of crows I have looked
at and listened to this summer at Cape Alava and Neah Bay, on the outer
Olympic coast.

In contrast, crows I usually see in the town of Sequim, associated with
agricultural lands and Safeway parking lots, do generally appear larger
to me and clearly have the typical, higher "cah" I know from American
Crow.

"In town" crows in Sequim sound very much like the crows I am used to
hearing in the interior, such as in the Yakima Valley, whereas Salt Creek
campground crows and Cape Alava crows clearly do not.

Yes, some crows at other Clallam County sites don't neatly fit these
descriptions and sometimes I'm left scratching my head, but something's
going on here that makes me suspect that we don't know the whole story.
My gut feeling is
>"Size will not get you there. Call will not get you there"
is not the reality in Clallam County. There may be some overlap in
sizes, but I must plead that more study is needed to really answer this
question. As we know from other sibling species, vocal dimorphism may be
a valid character for separating species, regardless of size, if
reproductive isolation occurs.

I also appreciate Eric Craig's discussion about the lack of agreement
between CBCs about these crows, especially between BC and Washington
counts. Clearly CBC compilers are not consistent about species,
especially with things like crows and gulls (Glaucous-winged X Western
hybirds, for example), so don't look to CBCs to solve this problem. In
Washington, we've been told to call everything "crow, sp.", because the
Records Committee is uncertain about crow systematics at this time. But
I'm beginning to think there really are two morphs (whether they are
species or not) of crows in Clallam County, now that I've taken the time
to look and listen to them. Now to collect some data!

As an aside, CBC compilers must be willing to admit that we can't ID
every bird, so sometimes the "sp." label is okay, if not preferred. We
get stuck in a trap of lumping questionable birds with whatever species
or group they seem to fit, instead of listing it as "sp." We must admit
that some birds can't be positively identified, whether by novice or
expert. For example, a large BC Christmas Count (which shall remain
nameless, but lies at the southern tip of Vancouver Island) last year
observed over 25000 gulls, all identified to exact species, with none
listed as "gull, sp." How is this possible? How can over 100 observers
count over 25000 gulls and every gull be accurately pigeonholed to
species? Clearly they can't. Probably two gull "experts" couldn't agree
on the exact identity of 100 of our local northwestern winter gulls, if
you threw in different ages and hybridization. Another example is that
some CBCs have significant numbers of accipiters, all speciated to
Sharp-shinned or Cooper's, but you know there must have been some
uncertainty about some of them. So my message is that among all CBC
counters and compilers more work is needed to make sure we are as
accurate as possible, but not more accurate than is possible.

Bob Boekelheide
Sequim