glaucoides - kumlieni

(last update: January 26, 2012)

Adult Thayer's Gulls (thayeri), three example birds. Pictures: Jeff Poklen.

This bird has an especially dark eye. Image 2 provides a comparison with Herring Gull. This would be a "Stage 4" bird, with darker grey or more extensive grey marks on the outer five primaries with complete subterminal bands on zero to three primaries. This stage 4 was scored in 55% of the adult Kumlien's at Newfoundland in the research by Howell & Mactavish. For explanation, see chart.

Thayer's Gulls (thayeri) adult, October 25 2004, Rio del Mar - California, USA. Pictures: Jeff Poklen.

Classic Thayer's Gull adult, still in active primary moult. Note blackish pigmentation on outer primaries and dark iris.

Thayer's Gulls (thayeri) adult, February 20 2004, Rio del Mar - California, USA. Pictures: Jeff Poklen.

Classic Thayer's Gull adult with pale iris. P5 can not be scored, but considering the extent of subterminal black on P6, there may well be some dark on P5 as well, and this would class it as "Stage 6" bird (with darker grey or more extensive grey marks on the outer six primaries with complete subterminal bands on three to four primaries among P6-P9). This stage 6 was scored in 5% of the adult Kumlien's at Newfoundland in the research by Howell & Mactavish. For explanation, see chart.

Thayer's Gulls (thayeri) adult, December 22 2008, Capitola - California, USA. Pictures: Jeff Poklen.

Classic Thayer's Gull adult. This would be a "Stage 6" bird, with darker grey or more extensive grey marks on the outer six primaries with complete subterminal bands on three to four primaries among P6-P9. This stage 6 was scored in 5% of the adult Kumlien's at Newfoundland in the research by Howell & Mactavish. For explanation, see chart.