www.gull-research.org

Is this a 4cy Caspian Gull?
photographed on 22th March 2012 in german midland

Greets Armin

no. surely not a pure cachinnans - but more likely a 3cy yellow-legged gull (it is definitely a 2nd cycle bird).
the dark underparts markings are unusual and let's say "hardly imaginable" for a cachinnans although even some 2nd cycle cachs can show dark on underparts and slightly dark underwings like this one. with the short wings and no p10 mirror and on the other side advanced covert moult (many adult grey coverts) there seems only the option of a 3cy male michahellis. tertial and covert pattern would fit. the "white hooded" look comes from the newly moulted head and neck while the dark feathers on the breast are retained 2nd basic ones. but i might be wrong - now come and tell me it's a herring gull
edit: i ask myself how a male 3cy argentatus x cachinnans could look and if it could be that advanced in grey coverts and bill coloration in 3cy march.

p.s. 4cy cachinnans usually has a large p10 mirror and a small p9 mirror and looks something like this: http://lou.bertalan.de/gulls/pic/vh/up_0679.jpg

edit: link fixed, a pic by razvan zinica from techirghiol lake, 21. march 2010.

lou

Lou, the link doesn't work.