Table 111 Continued


Moult in the breeding area before autumn migration

Moult partly in the breeding area before autumn migration, and partly in the wintering area after migration

Eurasian Sparrowhawk Accipiter nisus, Common Kestrel Falco tinnunculus, White-tailed Kite Elanus leucurus, Sharp-shinned Hawk Accipiter striatus, Common Black Hawk Buteogallus anthracinus, Red-shouldered Hawk Buteo lineatus, and other short-distance migrants Eurasian Hobby Falco subbuteo, Honey Buzzard Pernis apivorus, Mississippi Kite Ictinia mississippiensis, Swainson's Hawk Buteo swainsoni, Osprey Pandion haliaetus, Swallow-tailed Kite Elanoides forficatus, and other long-distance migrants a In addition to a complete post-nuptial moult, almost all shorebirds have a partial pre-nuptial body moult, which starts in winter quarters, and in some species continues into spring migration.

From Cramp (1992), Cramp & Simmons (1983), Jenni & Winkler (1994), Kjellén (1994b).

It is thus not only the sequence of events in the annual cycle that varies among species, but also their duration. The breeding cycle in different bird species can last from a few weeks to more than a year, as can a complete cycle of feather replacement (the latter often with breaks). In some short-distance migrants, both autumn and spring journeys can each take less than one day, but in some longdistance migrants, the autumn journey can take up to five months and the spring journey up to three, so that individuals are on migration for more than half the year (again with breaks). Some pelagic bird species also have extremely long migration periods, as they are 'stationary' only in the breeding season and effectively on the move for the rest of the year. Moreover, even during the 'stationary' periods, individuals of some pelagic species regularly commute hundreds of kilometres between their nesting and feeding areas (Chapter 1).

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