Wing and tail feather damage in Western Common Kingfishers Alcedo atthis ispida in relation to moult

Abstract

ABSTRACT Feathers have to be moulted to repair sustained damage. Our objective is to understand the relationship between the frequency of feather damage, feather sturdiness and moult sequence. Damage was recorded in five flight feather tracts for over 2000 Common Kingfishers Alcedo atthis ispida captured during a population study in northwestern Germany. We found that, of the feather tracts studied before the first moult, the tail feathers sustained most wear and damage, especially the more sturdily built outermost ones. Nevertheless, the probability of moulting a rectrix decreased from the central pair to the outside, while the damage risk increased. The sturdy distal primaries and the more lightly built innermost secondaries were the remiges with the highest frequency of damage, but not the most severe damage, while a row of midwing secondaries and primaries had the lowest damage risk. Where remiges had been retained when moult was suspended at the beginning of winter, about 75% of unmoulted feathers belonged to this low-risk group. The distal alula feather and the outermost primary covert had damage rates comparable to the low-risk row of remiges. Feather damage in the wings does not accumulate evenly over time, but increased markedly from March to April, coinciding with courtship and nest excavation, especially in females. Ultraviolet light seems to be an important factor for the observed feather deterioration, but is not the only one. The Kingfisher’s unusual moult sequence of remiges and primary coverts matches the distribution pattern of feather damage, but the sequence of the first tail-feather moult does not. Very few previous studies have investigated the relationship between patterns of feather damage and moult sequence. We hope this work encourages more investigation of this subject.