IORC Record 1927-001

Form: Western Gull
County: Cook
Location: Lincoln Park, Chicago
Date(s): 19 October and 17 November 1927
Number of birds: one
Remarks: This record is represented by specimen #1663 in the Chicago Academy of Sciences collection. Identified as a Great Black-backed Gull in the field, it was thought odd for that species and collected. Examination of the specimen following collection resulted in the conclusion that the subspecies identity was Larus occidentalis wymani. The Chicago Academy of Sciences collection contains a letter describing its re-identification by Dr. J.R. Jehl, Jr., curator of the Natural Sciences and P. Devillers in 1971 as pertaining to Larus occidentalis occidentalis. Subsequently, on 5 February 2011, Bob Hughes examined the specimen, concluded it was not a Western Gull afterall, and suggested the individual was a Western Gull x Glaucous-winged Gull hybrid. Following this, Doug Stotz resubmitted the record to IORC for reassessment. At the 1 December 2012 meeting of IORC, members voted to reject the record as pertaining to Western Gull. Amar Ayyash provided a detailed analysis of the specimen in Birding, vol. 46, no. 1, pp. 40-45, Jan.-Feb. 2014.

Additional material:

  1. Illinois Birders' Forum topic (accessed 7 Dec 2014) regarding the initial discovery that the identification as a Western Gull should be questioned.
  2. Note by E.G. Wright and E. Komarek in Auk, vol. 45, no. 2, p. 200 describing the initial discovery and collection
  3. Letter from Joseph R. Jehl, Jr. discussion the specimen.

Photographs submitted: four by Robert D. Hughes, four of the specimen

Photo #1 by Robert D. Hughes on 5 February 2011

 

Photo #2 by Robert D. Hughes on 5 February 2011

 

Photo #3 by Robert D. Hughes on 5 February 2011

 

Photo #4 by Robert D. Hughes on 5 February 2011

 

Photo #5 of Chicago Academy of Sciences specimen #1663 collected by Earl G. Wright

 

Photo #6 of Chicago Academy of Sciences specimen #1663 collected by Earl G. Wright

 

Photo #7 of Chicago Academy of Sciences specimen #1663 collected by Earl G. Wright

 

Photo #8 of Chicago Academy of Sciences specimen #1663 collected by Earl G. Wright

This page was last updated on 22 June 2023