Wing-feather mite (Acari: Proctophyllodidae) abundance correlates with body mass of passerine hosts: a comparative study

Data from a 4-year study of wing-feather mites on passerines in Portugal (Behnke et al. 1995. Exp. Appl. Acarol. 19: 443–458) were used to investigate whether avian body mass influences the abundance of mites. When 17 host species were used as statistically independent observations, the mite infestation score correlated positively with avian body mass. This correlation is not a phylogenetic artefact, having been also found when avian phylogeny was controlled for. Three non-exclusive hypotheses might explain this finding: (1) larger birds may provide larger "habitat islands," enabling more mites to coexist; (2) larger birds may provide more topographic refugia for mites to evade host preening; (3) larger birds may provide greater longevity of habitat islands, thus reducing the decimating effects of transmission.