Hello All,
I find this subject very interesting as it is my understanding that some
adult Ring-billed Gulls are most likely pink due to something they have
ingested and inherited. Yesterday along Mill creek there was a mixed flock
of California/Ring-billed Gulls numbering 40+ birds. There were 3 adult
Ring-billed Gulls that still maintained a noticeable pink wash even at this
late date. The pink wash becomes noticeable in late Feb. and is mostly gone
by early May. I also suspect that the pink birds have something else
involved other than just a food source issue. Other gull species that show
pink in alternate plumage are Franklins Gull, Ross' Gull and one tern
species , the Roseate Tern. Are all these pinks a result of diet? Or is it
hormones plus diet plus inherited traits equals pink plumage. Only adult
alternate plumaged birds display this pink wash in all species mentioned
here. Very interesting to me anyway.
Later Mike

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Mike & MerryLynn Denny
323 Scenic View Drive
College Place, WA 99324
509.529.0080 (h)

IF YOU HAVEN'T BEEN BIRDING, YOU HAVEN'T LIVED!
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