This first cycle gull was at Lindo Lake in Lakeside (San Diego County), CA, on 8 Feb 2015. Initial impression based on size and plumage was American Herring Gull (locally rare), but some plumage details and head structure don't fit well. The unusual plumage includes whitish rump (like Vega Gull), white patch in lower flank and broad white tips to secondaries (both like Western Gull). Head structure recalls Western or Glaucous-winged Gull. I think this may be Olympic Gull, i.e. hybrid Western x Glaucous-winged Gull. Opinions?