This page focuses on apparent hybrids among Glaucous Larus hyperboreus, Glaucous-winged L. glaucescens, Western L. occidentalis and Herring Gulls L. argentatus.  Where ranges meet, these so-called species seem to interbreed quite freely, producing offspring sporting a bewildering array of plumages.

The photos below are organized by day of the year.  Clicking on an image thumbnail will take you to a larger photo, often accompanied by analysis.  Tentative hybrid identification and ages are indicated.  If an individual is looks almost like one or the other of a Western Gull or Glaucous-winged Gull then its portrait will be found on those pages instead of here.

Discussion is welcome.  Please send your comments on identification and ages of these birds to Michael G. Shepard at info@birdinfo.com  Each of the thumbnails below is numbered for easy reference.

Please note that we are not actively collecting images of hybrids.  Our expertise in this matter is rather limited.