Premium
A parasite‐induced maternal effect can reduce survival times of fleas feeding on great tit nestlings
Author(s) -
Gallizzi Katharina,
Richner Heinz
Publication year - 2008
Publication title -
oikos
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.672
H-Index - 179
eISSN - 1600-0706
pISSN - 0030-1299
DOI - 10.1111/j.0030-1299.2008.16727.x
Subject(s) - hatching , biology , flea , offspring , brood , paternal care , zoology , maternal effect , blood meal , parasite hosting , reproductive success , ecology , pregnancy , population , demography , genetics , world wide web , computer science , sociology
Parents can increase their reproductive success by assisting their neonate offspring in parasite defence. In birds, parental tactics include post‐hatching parental responses such as increased parental care and pre‐hatching maternal effects such as the transfer of maternal antibodies via the egg. These parasite‐induced parental responses are known to reduce the effects of parasites on offspring, but their costs for the parasite are largely unknown. In two separate experiments on great tits Parus major we assessed these costs for hen fleas Ceratophyllus gallinae . Half of the parents where exposed to fleas during egg‐laying to induce the parental response, while control nests were left flea‐free. In experiment 1 parents raised their own young and we measured the effect of combined pre‐ and post‐hatching parental effects, while in experiment 2 a cross‐foster design allowed us to assess the effects of pre‐hatching maternal effects alone. In both experiments we let fleas take a blood meal on nestlings from either flea‐exposed or unexposed parents. We then measured flea‐feeding duration, the quantity of extracted blood, and the fleas’ subsequent survival time. We found in both experiments that on the largest nestlings of a brood flea survival was significantly reduced by the parental effects, whereas on the smaller nestlings it was independent of parental effects. The pre‐ and post‐hatching parental responses did neither affect duration nor size of a flea blood meal. These results suggest first that the pre‐hatching maternal effects, i.e. the substances transferred to the nestling via the egg, have the potential to harm fleas without reducing flea feeding capacity, and second that the strength of the maternal response varies between the nestlings, either because maternal products are unequally distributed among eggs within a clutch, or because large nestlings can build up a response that enhances the effect of the maternal products.