Behavioural responses to ectoparasites in pied flycatchersFicedula hypoleuca: an experimental study

Abstract

Nests of cavity‐nesting birds usually harbor some species of haematophagous ectoparasites that feed on the incubating adults and nestlings. Given the negative impact of ectoparasites on nestlings there will be selection on hosts to reduce parasite infestations through behavioural means. We have experimentally reduced the abundance of all ectoparasites in nests of pied flycatchers Ficedula hypoleuca to explore both whether there are changes in the frequency and duration of putative anti‐parasite behaviours by tending adults, as well as whether such anti‐parasite behaviours are able to compensate for the deleterious effects that parasites may have on nestlings. Heat treatment of nests substantially decreased the density of ectoparasites, and thereby positively affected nestling growth. The frequency and intensity of female grooming and nest sanitation behaviours during the incubation and nestling periods decreased as a consequence of the experimental reduction of ectoparasite infestation. Although nestlings begged more intensely in infested nests, the experiment had no significant effect on parental provisioning effort. Reduction of parasites resulted in larger nestlings shortly before fledging and increased fledging success. This study shows a clear effect of a complete natural nest ectoparasite fauna on parental behaviour at the nest and nestling growth in a cavity‐nesting bird. Although ectoparasites induce anti‐parasite behaviours in females, these behaviours are not able to fully remove parasite's deleterious effects on nestling growth and survival.

Males respond to female begging signals of need: a handicapping experiment in the pied flycatcher, Ficedula hypoleuca

“…All films were recorded between 0800 and 1500 hours, and no U=533.5, P=0.969). As in previous studies (Cantarero et al 2013a;2013b), no evidence of stress or unnatural behaviour such as extremely long periods of absence from the nest or trying to peck at the camera system were observed after the first visit.…”

“…No brooding is observed after nestlings attain 7 days of age (Sanz and Moreno 1995). Breeding activities are followed routinely every year and laying and hatching dates and brood sizes at hatching and fledging are determined (Cantarero et al 2013a). …”

“…Five and 10 days after clutch completion (days 6 and 11 of incubation) we recorded nest activity inside nestboxes for about 100 min (101.68 + SE 17.42 min, N=135) with a cold white light (LED 5 mm) powered by a 3 V battery and a camera (GoPro HD Hero1) mounted on the roof inside the nestbox (Cantarero et al 2013a). We obtained two incubation records for each nest, before and after treatment.…”

“…From records taken during incubation we estimated the proportion of time spent by the female inside the nestbox or 'egg attendance' which includes the time allocated to incubating and turning the eggs, and the mean duration of incubation sessions and recesses (Cantarero et al 2013a). In addition, we counted incubation feedings by males.…”

“…From recordings during the early nestling phase we obtained hourly provisioning rates by males and females and the amount of time spent by females on 'nestling attendance'. 'Nestling attendance' includes the proportion of time spent by the female inside the nestbox (Cantarero et al 2013a). We also counted male feeds aimed at the female and those aimed at the nestlings.…”