Dutch Birding volume 33 (2011) no 3

Kumlien's Gull at Brabantse Biesbosch in April 2011

On 3 April 2011, an adult Kumlien's Gull Larus glaucoides kumlieni was found during an excursion on a large freshwater reservoir at Brabantse Biesbosch, Noord-Brabant, the Netherlands, and observed for most of the day. The site is not open to the public and the bird was seen by just 13 birders. It was identified by its size (slightly smaller than Herring Gull L argentatus), dark iris (pale in adult Iceland Gull L g glaucoides) and obvious dark grey markings in the outer primaries (grey outer webs most obvious on p8-10; dark subterminal markings on p6-8, most obvious in p7). Thayer's Gull L thayeri or a hybrid Thayer's x Kumlien's was excluded by the pattern of the primary tips (darker in Thayer's or hybrid) as well as subtle differences in mantle colour, head shape and bill shape. If accepted, this is the second record for the Netherlands; the first was a second-winter on the beach of Terschelling, Friesland, on 30 January 2005.

Theo O V Muusse, Billitonstraat 19, 3312SB Dordrecht, Nederland
(theomuussechello.nl)