HI:
On the Glaucous-winged x western gull situation try reading:
Bell. 1997. Vol 99(3). Condor. This article is available on-line at
cooper.org by using there index to the CONDOR journal.

--
Ian Paulsen
Bainbridge Island, WA, USA
A.K.A.: "Birdbooker"
"Rallidae all the way!"