Special Issue on Avian Moult - Ostrich: Journal of African Ornithology

Feathers are the foundation of the grace and beauty for birds, but to keep them looking pretty behind the scenes, a crucial process unfolds—the annual replacement of the feathers, known as moult. A recent global review by Jenni and Winkler in 2020 shed light on the lack of information regarding moult in tropical and southern hemisphere birds. However, a pioneering approach to moult analysis originating in the Southern Hemisphere has paved the way for a deeper understanding of when, where and for how long these changes occur.

The replacement of worn and damaged feathers is vital for all birds, with flight feathers (remiges and rectrices). These feathers play a pivotal role in flight efficiency, impacting foraging success, parental care, and predator evasion. The moult period, during which birds must produce new feather material, poses challenges such as reduced insulation and waterproofing, along with potential compromises in flight ability.

Timing of moult is important in minimizing adverse effects on survival and reproduction. While much has been learned from the established approach to moult analysis, a gap in information persists for tropical and southern hemisphere birds, particularly in Africa.

For many African bird species, essential information on the timing and duration of moult, gender differences, and regional variations is still lacking. Understanding the extent of overlap between moult and breeding at both population and individual levels adds another layer of complexity. In this special issue of Ostrich, leading ornithologists fill some of these gaps for some of Africa’s bird species, although there is still much to be contributed on the topic.

Issue 94 of Ostrich: Journal of African Ornithology is a special issue on Avian Moult which was overseen by renowned ornithologist Professor Adrian Craig, assisted by Dr Birgit Erni, experts in birds and statistics.  

The special issue of Ostrich presents a snapshot of the current status on our knowledge on the topic of moult, including important advances in how to improve estimations of when birds start moulting, as well as how to use generalized additive models to improve an understanding of the annual moult cycle. Researchers, having been involved in both data collection and analysis methods, express hope that this collection of research will inspire a broader exploration of moult in different ecological situations and among a diverse range of bird species. 
The Special Issue will be available to read at no cost until the end of March here. 

Checking for wing molt and beautiful colours on this Emerald Spotted Wood-dove - Credit