| dc.description.abstract | SUMMARY
Background: Lice are common ectoparasites of birds, completing their entire
life cycle in the plumage. Transmission – in most cases – requires physical contact between hosts. Lice may benefit from choosing host individuals with better
survival prospects and dispersal chances. Bodily contacts between parents and
offsprings provide a good opportunity for host selection. The Common Kestrel
is a widespread, small-bodied raptor of the Palearctic region, with well-known
breeding biology and ectoparasite fauna, making it suitable to study the ecological correlates of vertical transmission of lice.
Objectives: The aim of our study was to investigate how the sex, maturity and
clutch size of Common Kestrel nestlings affect the abundance of their lice.
Materials and Methods: Field work was carried out in Körös-Maros National
Park Directorate (Hungary). The ectoparasites were collected from nestlings (n
= 54) with dust-ruffling. The effect of the host’s sex, wing length and clutch
size on the abundance of their lice was analysed using negative binomial mixed
models.
Results and Discussion: In case of Colpocephalum subzerafae, none of the
investigated variables had a significant effect. Contrarily, clutch size had a significant effect on Degeeriella rufa abundance. In small clutches (3–4 nestlings)
the mean abundance of D. rufa (15.5 95% C.I.: 8–30) is 3.7 times higher, than in
large (5–6 nestlings) clutches (4.2 95% C.I.: 2.3–7.4). We discuss two non-exclusive explanations of this pattern. First, parental quality is known to affect
the clutch size. If low quality parents are also more heavily infested with lice,
this could explain the higher louse load of their nestlings. Alternatively, according to the dilution hypothesis, long life-cycle ectoparasites (such as lice), that
are incapable to significantly raise their subpopulation size till the fledging of
the chicks, disperse among the nestlings, resulting in lower per nestling louse
counts in larger clutches. According to our results both the breeding parameters
and the quality of the parents may affect their offsprings’ ectoparasite load. | en_US |
