Die postnuptiale und die praenuptiale Vollmauser von Pericrocotus divaricatus Raffles

Abstract

Pericrocotus divaricatus not only surpasses all other members of the family Campephagidae by the length of the migration route, but has also the peculiarity of moulting the whole plumage twice each year. The complete postnuptial moult takes place on the North-Asiatic breeding grounds and lasts from the beginning of July to early (or mid?) September. The complete prenuptial moult starts after mid-December in tropical winterquarters and ends almost regulary in the second half of March. In both sexes "winter plumage" and "summer plumage" are alike. Just as in Lanius tigrinus the postnuptial moult proceedes at a faster rate than the prenuptial; the sequence of feather renewal, however, is the same in both cases and follows the pattern which many passerine species have in common. Autumnal migration and spring migration begin as soon as all feathers are renewed. Young birds, at first covered with a spotted nestling plumage, moult in late summer all body feathers before migrating south. This moult leads to a juvenal plumage very similar to that of the adult female, which is completely replaced in winterquarters by the sexual-dimorphic adult plumage (exactly as in Lanius collurio). © 1972 Verlag der Deutschen Ornithologen-Gesellschaft.