Ecological and anthropogenic influences on patterns of parasitism in free-ranging primates: a meta-analysis of the Genus Alouatta.

KOWALEWSKI, M MARTIN; GILLESPIE, THOMAS R

South American Primates, Developments in Primatology: Progress and Prospects

Springer Press

Lugar: Chicago, IL, USA; Año: 2009; p. 433 - 461

Parasites play a central role in ecosystems, affecting the ecology and evolution of species interactions, host population growth and regulation, and community biodiversity. Howler monkeys are the most widespread nonhuman primates in South America, with 8 of 10 Alouatta species living in South America. We took a meta-analysis approach, integrating data from studies on wild Alouatta caraya, A. seniculus, A. guariba, and A. belzebul, to examine how various factors such as latitude, altitude, annual precipitation, continuous or fragmented forests, and degree of contact with human settlements affected parasite prevalence. We included in the analysis data on the prevalence of gastrointestinal parasites, blood parasites and ectoparasites, and number of parasite species.When all parasite types were analyzed together we found that type of human contact affected the prevalence of different parasites (P < 0.05). Our general analysis suggests that the prevalence of parasites did not vary across fragmented and continuous forests (P > 0.05). Logistic regression models suggested latitude and altitude were mediators of the likelihood of having high or low parasitic prevalence (either higher or lower than 20%) (P <0.05). The relationship between gastrointestinal parasite diversity at a study site and average annual precipitation was positive and significant (r = 0.72, P < 0.05). Almost 86% of gastrointestinal parasites, and 100% of blood-borne parasites found in howlers are found in humans. Our results provide a baseline for understanding causative factors for patterns of parasitic infections in wild primate populations and may alert us to imminent threats to primate conservation.