Consistent individual differences in ecto-parasitism of a long-lived lizard host

Individual hosts vary substantially in their parasite loads. However, whether individual hosts have consistently different loads remains uncertain. If so, hosts that have consistently high parasite loads may serve as key reservoirs or super-spreaders. Thus, identifying whether individuals persistently differ in their parasitism and the factors that explain these patterns constitute important issues for disease ecology and management. To investigate these topics, we examined nine years of tick counts in a wild population of sleepy lizards, Tiliqua rugosa. Lizards were individually marked, and throughout their activity season, often across several years, we repeatedly assessed lizards’ ticks (to stage – larva, nymph, adult male, and adult female – and species, either Bothriocroton hydrosauri or Amblyomma limbatum). Using these repeated individual measures, we determined whether tick counts were repeatable. Then, we tested predictors of average tick counts, particularly lizard mass, sex, b...