Life history traits, habitat characteristics, and phylogeny influence tick infestation probability in tropical wild birds

Interactions between wild birds and ticks exert significant selective forces, influencing the host's evolution and fitness. Tick infestation rates vary among bird species due to life history and morphology. Understanding tick infestation probability is crucial for conservation efforts, as birds play an important role in the tick life cycle and can transmit tick-borne pathogens. In this context, it is essential to understand how life history traits or phylogenetic relationships determine tick infestation probability in the tropics. This study aims to identify wild bird life history traits and habitat characteristics associated with tick infestation probability in the Colombian tropical region. We hypothesized that larger body size, migratory behavior, foraging in lower vegetation stratum, seasonal aggregation, and inhabiting natural habitats increase tick infestation probability. We used a dataset with 3488 wild bird records from 322 species and 41 families, obtained from 61 Colombian localities (26 in the Orinoquia and 35 in the Andean regions). We used phylogenetic generalized linear mixed Bayesian models to assess tick infestation probability based on life history traits, body size, and geographic distribution. Of the birds analyzed, 3.2% were infested by ticks, mainly in immature stages (95%). Our results indicated a lower probability of tick infestation in agricultural habitats and higher elevations. Ground-foraging species exhibited a lower infestation probability, contrary to previous reports. We found a significant phylogenetic relationship, indicating that related species have similar probabilities of tick infestation compared to more distantly related species. This study provides valuable insights into the bird–tick association, with implications for disease management and bird conservation.