Thayer's Gull - Larus thayeri

On Saturday 11 April 2015 at 20:18 hours I habitually checked my smartphone and suddenly two messages popped up, one from 19:52 hours and one at 20:09 hours. They were both from Leon Edelaar. The first said "Thayers or Kumliens at Egmond, come now!", the second said: "I go home as nobody is interested in %&$ gulls". I knew I would never make it in time. Driving from Alkmaar to Egmond is 15 minutes and parking the car and running to the spot is another 15 minutes. So I answered him I could not come, but immediately asked if he had photographs, so Leon sent some pictures both on the mail and our Whatsapp group. At 20:37 hours Wim van Splunder - while attending a football match in Heerenveen Fr - answered he thought it was more a Thayer's than a Kumlien's Gull. Leon had come to the same conclusion and I couldn't agree more.
Leon also consulted Peter Adriaens, a Belgian birder who had studied Smithsonian, Kumlien's and Thayer's Gull in detail, and Mars Muusse, one of the founders of the international gull site on gull identification, Gull-research.org. Peter answered Leon it had to be a Thayer's Gull Larus thayeri and the same he replied on the forum of waarneming.nl. The next day we all gathered at first light and at c 8:12 Vincent van der Spek discovered the bird between hundreds (if not thousands) of other large gulls. The bird passed us along the shore and disappeared to the east into the village of Egmond aan Zee.
At 9:30 we realized the bird was difficult to relocate so we thought it was time to celebrate the bird and we needed some coffee too. So together with Vincent Hart, Roelof de Beer, Rob Halff and Marten Miske I went to a restaurant on the beach (in Dutch called a strandpaviljoen). After drinking coffee and eating apple pie we made some phone calls, leisurely looked at the sea and then we spotted a gull in front of the pavillion. It turned out to be the Thayer's Gull! We all made pictures at close range but then the bird was disturbed by some joggers and it disappeared to the sea again flying north. Happily birders on the beach found it again. It was seen intermittently till 16:30 by c 200 birders. The next day however it could not be relocated, but from 14 April it was found again at Bergen aan Zee, c 5 km north and was seen there till 21 April.
For Leon it was a big reward for his years of thorough scanning all large gulls, looking for Smithsonian Gulls. He may have founded one already, but the day will come he find one everybody can see when giving the chance. Or another rare gull.

One of the first pictures made by Leon; tail pattern and colour, lighter inner primaries and all dark bill point towards Thayer's;
11 April 2015, Egmond aan Zee NH; © Leon Edelaar.

The primaries are dark brown-grey with whitish fringes forming chevrons, the tertials are lighter grey brown and patterned at the top;
also the underparts are a shade darker than the upperparts and quite uniform, not spotted; note also the pink legs;
12 April 2015, Egmond aan Zee NH; © Jan van der Laan.

Note the patterned median coverts and greater coverts as well; the ear coverts are dark. From this angle the head looks darker.
The bill has some pink at the base of the lower mandible; 12 April 2015, Egmond aan Zee NH; © Jan van der Laan.

Note the silvery wash on the underside of the primaries demarcated by dark tips; on the upperside the outer primaries have a dark outer flag and light inner flags;
the four inner primaries are light with ony a dark spot on the tips, the secondaries are grey brown with light tips; the rump is striped brown and white;
the tail is all dark grey brown with only lighter bases at the outer rectrices. 12 April 2015, Egmond aan Zee NH; © Jan van der Laan.

Note the bird's size. It is the same size as European Herring Gull Larus argentatus or the Pontic Gull Larus cachinnans in front. 19 April 2015, Bergen aan Zee NH; © Jan van der Laan.

Short footage on 18 April 2015, Bergen aan Zee NH; © Kees Klaij.

In February 2016 it was accepted as the first record in the Netherlands. Thayer's Gull is very rare in Europe with about 20 records, e.g. Ireland (six records, in 1990, 1998, 1998/1999, 2003, 2012 and 2013), United Kingdom (six records, in 1997, 2010, two in 2012, 2014 and 2015), Iceland (at least seven, in 2004, 2005, 2008, 2012, 2013 and two the past winter), Spain (a long stayer between 2008 and 2015), Denmark (two, in 2002 and 2012), Norway (one in 2000) and the Faeroes (one or two, 2009 and perhaps 2012).

Do you want to go to the main-index, the 2015-index or the next species, the Siberian Rubythroat?