The effect of ectoparasite nest load on the breeding biology of the Penduline Tit Remiz pendulinus

Abstract

In this study we investigated the importance of ectoparasite load in the nest on the breed‐ing system of the Penduline Tit Remiz pendulinus, examining the effect of mite abundance in the nest on mate choice, reproductive success and parental effort. The two most common ectoparasites were the Northern Fowl Mite Dermanyssus hirundinis and the Northern Feather Mite Ornithonyssus sylviarum. The results show that mite load is important in mate choice but has no adverse effect on reproductive success. The results also indicate that infestation level is related to the quality of the male (mask‐width). Parental feeding rate was negatively related to mite load. This relationship indicated that Penduline Tits did not compensate for higher parasite loads by increasing feeding but rather reflected the con dition of the parent and its investment in self‐maintenance behaviour.