Gene Hunn, Seattle, hunnhome at accessone.com

Tweets,

On the Tropical/Couch's Kingbird thread: I reviewed my AOU checklist, Howell
& Webb's Mexican Guide, Birds of the West Indies, Rare Birds of the West
Coast, and Birds of South America and think we can safely eliminate all but
Tropical & Couch's from consideration, given 1) bright yellow breast &
belly, 2) blackish-brown tail, 3) not especially contrasty gray head but
with a dark eye patch, 4) greenish back, and 5) relatively large bill.
Eastern, Gray, Loggerhead, and Giant Kingbirds are all basically gray &/or
black & white; Western and Cassin's have relatively small bills and black
tails; Thick-billed Kingbird (which has occurred once on Vancouver Is., as
has Gray Kingbird) juvenile can have a rather bright yellow belly but has a
blackish hood contrasting with the white throat and has a particularly huge,
heavy bill; two South American species, the White-throated and the
Snowy-throated Kingbird are smaller with black tails (according to my aged
De Schauensee).

Couch's is restricted to the Gulf lowlands of Mexico s to the Peten of
Guatemala & Belize and exhibits limited migratory retraction from the
northern edge of its range in s. Texas. Tropical's breed throughout Mexico
and south into southern S. America and are migratory at both ends of their
range. The typical pattern of late October/November west coast appearances
of immature Tropical/[Couch's] along our outer coasts (normally) might fit a
"reverse migration" anomaly, young birds moving off 180 degrees from the
normal path, as I believe is known to occur in some species. It is striking
that the vast majority of Tropical-types stay put only briefly, as if they
were on their way somewhere else.

In short, although Couch's is not impossible it seems much less likely than
Tropical Kingbird, all things considered.



At 07:00 PM 10/25/97 -0700, you wrote:
>Hi Tweets,
>
>In view of the presumptions of Tropical and Couch's Kingbirds post-breeding
>dispersal and our resulting assumptions that 'all' West Coast
>late-fall/early winter yellow-bellied kingbirds are Tropical, the following
>news story in Peter Whelan's 'Birds' column in today's (Oct 25 1997) Globe &
>Mail may be instructive to those unwilling to call them anything but
>Tropical Kingbirds.
>
>Note: Nova Scotia (N.S.) is one of the Maritime Provinces on Canada's East
>Coast; Cape Sable Is. is well off-shore in the Atlantic, and a storied
>migrant trap for late-fall mirror-migrants.
>
>
>Section D, page 8
>
> A strange bird at Caple Sable Island, N.S. seems either to be the first
>Couch's kingbird (sic) seen in Canada or the first tropical kingbird (sic)
>identified east of British Columbia.
> Photographs were taken, but even if they're perfect they will probably
>not help. The two species are near-twins. They are flycatchers, almost
>robin-sized, pale-grey-headed and yellow-bellied with dark wings and tail.
>Both species reside in Mexico with scant outposts over the U.S. border.
> At first sight on October 16, the bird was taken for a western kingbird
>(sic)--the expected rarity of this general description. Then the larger
>bill, dark grey eye patch, greenish back and lack of white outer tail
>feathers denied this identification.
> What *does* (ital) separate Couch's and tropical kingbirds are their
>distinctive calls. The visitor's calls were heard by several birders. Later,
>one said, "That's it!" when a tape recording was played of the shrill
>'breeer' of Couch's kingbird. However, no recording was made of this bird.
> About 10 of the growing core of enthusiastic but inexperienced local
>birders saw the kingbird, with the last sighting at dusk. Halifax (N.S.--
>mp) experts arrived the next morning, too late; it was not seen again.
> Without recordings, this bird is expected to go down as a sight record of
>Couch's or Tropical kingbird.
>
>--end quote.
>
>First, the importance of recording: what would be the working radius for
>bird-song of a small fifty-buck microcassette tape recorder, given no or
>little wind and no traffic noise?
>
>Second, even more necessary become the most detailed field descriptions
>possible of these birds.
>
>Michael Price We aren't flying...we're falling with style!
>Vancouver BC Canada -Buzz Lightyear, Toy Story
>mprice at mindlink.net
>
>
>