Jack,

Maybe so, but a wide range of mantle color has been described for them, and
the birds that were by general agreement Slaty-backs near Portland, Oregon a
few winters ago were certainly no darker than our Westerns. Also, the
Slaty-backed we had at the Elwha River mouth, the first state record, I
forget the date, but just a year after the St. Louis bird which was the
first south of Alaska, apparently, while darker than our Westerns, showed
(as did the St. Louis bird) a very striking winter head pattern of heavy
blotchy streaking on the nape and a large dark patch all around the eye. If
this is not typical then they certainly vary all over the map.

Gene Hunn.

At 12:34 AM 10/17/97 PST, you wrote:
>** Reply to note from Gene Hunn
>
>>
>> Other perhaps off-the-wall possibilities include Slaty-backed (pale eye and
>> highly variable mantle color to as pale perhaps as California), Vega Herring
>> Gull (from Siberia) which I think would have an iris like our Herring but
>> which is somewhat darker, perhaps Mew Gull shade. Both Slaty-backed and Vega
>> Herring (or a hybrid between them) would have a less heavy bill than a
>> Western or Glaucous-winged X Western. However, both should by now have
>> rather heavily streaked heads.
>
>I spent the winter of 1983-84 on the n. Pacific with Slaty-backeds and the
other
>maritime gulls. I did not notice much variation in mantle color of the SBGU,
>all being a fairly dark slate gray; not as dark as a Greater Black-backed, and
>almost as dark as a _wymani_ Western. Also, there really isn't all that much
>winter head streaking on an ad. SBGU; not as immaculate as a WEGU, but
>definitely cleaner than a Glaucous-winged. Irides were mostly honey-yellow in
>adults. I saw one _vegae_ Herring Gull and you wouldn't be able to mistake them
>with SBGU once familiar with them - a shade lighter mantle than SBGU and not as
>truncate in jizz. Yes, the gonydeal swelling is slight on SBGU (much like
>Thayer's in this respect) which leads to a slimmer-billed look than any of its
>close cousins.
>
> - Jack
>
>
>
>Jack Bowling
>Prince George, BC
>jcbowling at mindlink.bc.ca
>
>