Moult and plumage

Author:
Open Access
Publisher website
Google Scholar
Abstract
Moult is one of the three main energy‐demanding events in the yearly cycles of birds, and in most species occurs at a different time from breeding and migration. The sequence in which these events occur varies according to the ecological circumstances in which particular populations live, and in general moult is more variable in timing than other events. Some migratory birds moult in their breeding areas after nesting is over; others moult at a staging area on migration; while others moult in winter quarters. Yet others show a split moult, replacing part of their plumage in one place and part in another, moult being arrested during the intervening migration. Different variants in these patterns occur in different populations of the same species. Some types of birds overlap breeding and moult, and some also overlap moult and migration, especially body moult which can occur without reducing flight efficiency. Most of our knowledge of moult is based on museum skins and, now that appropriate statistical models are available to analyse it, moult is increasingly being studied in free‐living birds, the main parameters of ecological interest being its timing and duration. Recent models for analysing moult data, and some of the pitfalls, are discussed briefly in this paper. More field study of moult is needed, particularly because of its relevance to annual cycle and population processes, and hence to its potential application in conservation‐based research. Ringers are the only people at present able to fill this gap in knowledge.

This publication has 23 references indexed in Scilit: