Larus cachinnans
(last update:
Greg Neubauer
Marcin Przymencki
Albert de Jong
Mars Muusse
cachinnans plumages
Larus argentatus sensu lato 3P00 adult, May 04 2014, Zastów Karczmiski, Poland. Picture: Łukasz Bednarz ringing team.
Location: Zastów Karczmiski, Poland - colony at the banks of the Middle Vistula river.
In 2004 240 breeding pairs (95% cachinnans, <5% argentatus). (Ornis Fennica 2011 88, 80-89) and in 2012 592 pairs (90% cachinnans, <10% hybrid / argentatus) and possibly Larus michahellis (pers comm. Łukasz Bednarz).
Middle Vistule river is a location where several taxa breed: see composition. Since this is a mixed breeding population where hybridisation is not uncommon, the ringing centre in Poland decided to label birds "Larus argentatus sensu lato". Still bulk of the breeding birds in Middle Vistula region show features of cachinnans.
below: Larus argentatus sensu lato 3P00 adult, May 04 2014, Zastów Karczmiski, Poland. Picture: Łukasz Bednarz ringing team.
Breeding bird trapped at the nest. Adult, with yellow legs, much black in wingtip, no mirror on P9, short pale tongue on P10, much black on innerweb of P8, full broad band on P5, red gape, red orbital ring, heavy bill with obvious gonys and red bleeding up onto the upper mandible. All feature point to adult Yellow-legged Gull michahellis.
below: Larus argentatus sensu lato 3P00 adult, June 28 2014, Zastów Karczmiski, Poland. Picture: Łukasz Bednarz ringing team.
