Hi all,

Lisa Hardy of Idaho asks whether anyone has noticed Ring-billed or other
pink-plumaged gulls this year. Her post to Inland Northwest Birders and
me follows this contact info...

Please respond to her directly at:

basalt at earthlink.net

Thanks,

Todd Hass
UW, Seattle
thass at u.washington.edu



"The pink is a delicate tinge through the white feathers of the head and
body, but quite distinct at close range and adjacent to normal white
birds.My first thought was that they had been dyed for a research project,
but close study revealed that the leg color was also different - a darker
orangey-yellow contrasted with the greenish-yellow of a normal bird. So
whatever accounts for the color must be systemic. Grant (1986) notes that
the pink coloration on some gulls and terns is due to pigmentation in the
preen-gland oil, which is transferred to the feathers during preening, and
thus is absent or less pronounced on the head which cannot be reached by the
bill in preening."

I am collecting quite the file on these sightings - they have been seen in
WA, OR, NV, and ID, the first report coming from NV on March 11. Everybody I
talk to suggests that it is something in their diet (such as carotenoids),
but the only specific suggestion is that they are eating brine shrimp
somewhere in the desert. One birder in Idaho said he has seen only one pink
RBGU in 40 years, that was in 2000. Another birder says she sees them in
small numbers every year. Yesterday in Coeur d'Alene I looked over about 350
Ring-billed Gulls, and I estimate there are about 2 pink individuals in a
hundred. I think there is something out of the ordinary this year - perhaps
a population spike in some sort of marine (or other) invertebrate or a new
menu item at McDonald's.

I would appreciate if you would post a query to Tweeters. If people include
dates when they saw the gulls, it might be possible to track where they are
coming from. Also, if it is some coastal diet item, there may be other
species of gull picking up the pigment. No one else seems terribly
interested in this, and I would be glad to have people respond directly to
me and I will try to put together a time-distribution map.

Thanks for your help!

Lisa Hardy
Kingston, ID