Herring Gull (Larus argentatus)
River Warbler (Locustella fluviatilis)
Large gull with deep chest, light grey back and heavy yellow bill with red spot (adult). Pinkish legs and black tipped primaries with white windows. Winter plumage with streaked head and neck. Develops grey mantle in 2.nd winter. Young birds may be difficult to distinguish from juvenile Greater- or Lesser Black-backed Gulls, and the species shows notable variation in both plumage and size. Juveniles generally shows darker head and less contrasting markings than Greater Black-back, and pale inner primaries (window), as opposed to the all black hand of young Lesser Black-backs.
Sound:Quite vocal. A long and strong "ay-kay-kay-kay-kay" with fading strength commonly heard. A deep "ga-ga-ga" heard from anxious birds. All calls much deeper pitched than Common Gull. Difficult to distinguish from Lesser Black-backed Gull, but tone is less nasal.
Contact call and song:
Distribution:
Wikipedia: map (se also Xeno-canto below)
Ecology:Birdlife ecology
Links:
Observation.org Latest observations
Image search Flickr NB! May give other species
CCA long-tailed and relatively long-winged Locustella, with olive-brown plumage and pale belly. Conspicuously broad, rounded tail, and substantial vent. Under tail coverts brown with with prominent pale fringes, and almost reaches tail tip. Faintly streaked throat and breast. Rump and tail warmer brown than back. Faint and short supercilium and pale eye-ring. First long primary with pale outer web, and a slight curve. Song-posts often more exposed than Grasshopper Warbler.
Sound:Song an insectlike, buzzing like Grasshopper and Savi's Warbler, but easily distinguished from those by it's distinct steam locomotive-like rhythm. About 8 accents per second. Perhaps easier to confuse with certain species of ground crickets or cicadas than it's congeners. Contact call a sharp "tsikk-tsikk", similar to Savi's Warbler.
Song:
Distribution:
Xeno-canto: map
Ecology:Birdlife ecology
Links:
Observation.org Latest observations
Image search Flickr NB! May give other species
CC