Every May since 2014, I've made it a point to run up to Wisconsin at the height of migration to attempt to see as many gull species possible. 8-9 species is relatively "easy" to get, with 10 being a good day. Yesterday, 26 May 2019, I tallied 9 species in Sheboygan and finished up with my 10th in Port Washington.
Sheboygan: Franklin's (1 sub-adult), Laughing (1 adult), Little (2 first cycle), Bonaparte's (~250; 95% first cycle), Ring-billed (~200; 80% first cycle), Herring (~300; 90% first cycle), Iceland (2 second cycles), Lesser Black-backed (4; two third cycle, two first cycle), California (second cycle).
Port Washington: 1st/2nd cycle type Glaucous Gull.
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2nd Cycle California Gull (PB2 molt in motion with inner primaries molting). New scapulars, several tertials and inner upperwing coverts via 1st prealternate.
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1st Cycle Little Gull (lower left) with similar-aged Bonaparte's Gull. Gray scaps likely formative. Black cap coming through most likely via 1st prealternate. |
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Same Individual Above. Note the darker, and thus stronger, outer webs to the primaries are entact. |
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1st Cycle Bonaparte's with nearly complete hood - an exception to the rule. Entire upperwing appears juvenile. Scapulars are formative, while the black head and white neck are 1st alternate. |
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Adult Herring Gull glamour shot. One of only a handful of definitive adults seen in Sheboygan. |
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2nd Cycle Thayer's Gull. The protected secondaries and tailband were sufficiently dark. The scapulars (at least the outer and lower feathers) and 2-3 new upperwing coverts are likely 2nd alternate.
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1st Cycle Herring Gull with upperparts recalling Vega HERG, although the well-marked uppertail was typical Smith. Scapulars are 1st alternate, likely acquired last fall. Median coverts emerging (flat gray), perhaps best attributed to first prealternate molt resuming in spring. |
This is only my second time seeing California Gull in the spring/summer season in Wisconsin and it's reassuring to know an 11th species - Great Black-backed Gull - was possible in Manitowoc. Other species that I think are real possibilities for a "Big Gull Day" in this region are Black-legged Kittiwake and Slaty-backed Gull. The latter is a highly desired bird outside of the winter season!