Evidence for partial prenuptial moult in adult and first-year Penduline TitsRemiz pendulinus

Abstract

Contrary to earlier accounts, this paper suggests that both first-year and adult Penduline Tits undertake a partial prenuptial moult. This moult is more extensive in first-year birds than adults and includes the replacement of body feathers, marginal and median wing coverts and a variable number of greater coverts, rectrices and inner remiges. Most flight feathers and greater coverts renewed during the first prenuptial moult are probably replaced from the point that the previous post-juvenile moult had finished and the subsequent moult occurs sequentially. This complementarity between post-juvenile and prenuptial partial moult seems exceptional among European passerines. Males tend to renew more of their plumage between the summer and winter moult periods. The extent of the first prenuptial moult was negatively correlated with the extent of the previous post-juvenile moult. It is suggested that this is due to the small advantages provided by a more extensive prenuptial moult after a given level of plumage...