The Biology of Moult in Birds

Unique to birds and with a multitude of functions, feathers are amazing structures. All birds need to renew their feathers periodically, in a process called moult. Because feathers can only be renewed as a whole, all functions of the plumage are impaired during moult, and so this process has a crucial impact on most aspects of a bird’s life. Therefore the period of moult is one of the most important recurring annual events in the life of a bird, together with reproduction and, for many, migration.

Every moult determines the appearance of the individual bird anew. An intense moult profoundly affects the physiology of a bird, with this normally lasting for up to three months of the year. Moult affects the organisation of the bird’s annual cycle of life, and constrains reproduction and migration. Given the major impacts of this process on birds, moult remains a sorely neglected field of ornithological research. This book, written by the internationally renowned ornithologists Lukas Jenni and Raffael Winkler, seeks to redress this.

Early chapters provide an overview of the functions of the plumage. Later, it moves on to subjects such as plumage maintenance and feather wear, the two main functions of moult; feather-growth, the physiology, energetics and control of moult; and how moult affects plumage quality, structural quality and coloration, and the consequences of this for the bird. The book concludes with a review of the various solutions developed by birds to fit moult into their annual cycle.

Complementary to the magnificent Moult and Ageing in European Passerines by the same authors and packed with colour photography throughout, The Biology of Moult in Birds is the first comprehensive review of all aspects of the biology of moult, drawing information from across the literature and in all birds, from penguins to passerines.