Do parasitic common goldeneyeBucephala clangulafemales choose nests on the basis of host traits or nest site traits?

Abstract

Conspecific brood parasitism (CBP) is an important alternative breeding strategy for gaining reproductive output in birds. While interactions between hosts and parasites and consequences of CBP to breeding success of both parties have been studied a lot, the roles of host characteristics and nest site characteristics in CBP have received less attention. We studied the relative importance of host‐related traits, such as female condition and breeding experience, and nest‐site‐related factors, such as overall nest site preference and occupation rate, in explaining the occurrence of CBP in a common goldeneye Bucephala clangula population. We used spatially and temporally extensive data sets, analysed the data with generalized linear mixed models that allowed us to account for the non‐independency of individual nesting attempts across females and nesting sites, and used an information theoretic approach in model selection and inference. About half of the nests were parasitized annually during the seven year study period. The occurrence of CBP decreased with advancement of the breeding season but late nests were also frequently parasitized. We found that the occurrence of CBP was better explained by nest‐site characteristics than host traits, implying that parasitic females target a given nest based on factors related to the nest site itself rather than on the host. Our results suggest that more attention should be paid to factors associated with nest site attractiveness and quality when studying laying decisions of parasites and the occurrence of CBP in general.

Spring phenology and timing of breeding in short‐distance migrant birds: phenotypic responses and offspring recruitment patterns in common goldeneyes

“…One might ask if the exclusion of failed nests could mask putative effects of varying breeding phenology. Most (38%) failed nests (n = 459, 1985–2008) were deserted during egg laying, likely due to conspecific brood parasitism (Paasivaara et al ). About 29% of nests were abandoned during incubation for reasons other than human disturbance or predation.…”

Do environmental conditions experienced in early life affect recruitment age and performance at first breeding in common goldeneye females?

“…Milonoff et al () reported that goldeneye females that have a skip year in breeding will advance, not delay, breeding after the skip. Finally, parasitic egg laying is a common reproductive tactic employed by goldeneye females in our study population (Paasivaara et al ). We cannot exclude the possibility that sexually mature females laid parasitic eggs in years before they started normal nesting but even that tactic would have been inferior to normal nesting in terms of fitness (Åhlund and Andersson ).…”

Intraspecific avian brood parasites avoid host nests infested by ectoparasites

“…Second, Cliff Swallows (Petrochelidon pyrrhonota) prefer to parasitize old rather than new nests, which may be a guarantee of its structural stability (Brown and Brown 1991). Third, probability of parasitism in nests increases with the number of previous nesting attempts and occupation rate in Common Goldeneyes (Bucephala clangula) (Paasivaara et al 2010). Fourth, Common Goldeneyes select host nests with reduced predation risk (Pöysä 2006;Pöysä et al 2010).…”