The anthropogenic environment lessens the intensity and prevalence of gastrointestinal parasites in Balinese long-tailed macaques (Macaca fascicularis)

Abstract

The distribution of wildlife parasites in a landscape is intimately tied to the spatial distribution of hosts. In parasite species, including many gastrointestinal parasites, with obligate or common environmental life stages, the dynamics of the parasite can also be strongly affected by geophysical components of the environment. This is especially salient in host species, for example humans and macaques, which thrive across a wide variety of habitat types and quality and so are exposed to a wealth of environmentally resilient parasites. Here, we examine the effect of environmental and anthropogenic components of the landscape on the prevalence, intensity, and species diversity of gastrointestinal parasites across a metapopulation of long-tailed macaques on the island of Bali, Indonesia. Using principal-components analysis, we identified significant interaction effects between specific environmental and anthropogenic components of the landscape, parsing the Balinese landscape into anthropogenic (PC1), mixed environment (PC2), and non-anthropogenic (PC3) components. Further, we determined that the anthropogenic environment can mitigate the prevalence and intensity of specific gut parasites and the intensity of the overall community of gut parasites, but that non-anthropogenically driven landscape components have no significant effect in increasing or reducing the intensity or prevalence of the community of gut parasites in Balinese macaques.

Mammalian gastrointestinal parasites in rainforest remnants of Anamalai Hills, Western Ghats, India

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“…Of the seven species of Giardia sp., G. intestinalis is known to infect humans, cattle, dogs and cats, and cause gastrointestinal distress. However, species like G. muris is host specific and transmission to humans is rather rare (Johnston et al 2010;Lane et al 2011). Studies have shown that Giardia sp.…”

Ecology and Epidemiology of Nematode Infection in Japanese Macaques:

“…Unfortunately, our ability to predict specific disease outcomes of such changes remains poor Chapman et al 2009b). The growing body of literature addressing potential impacts of anthropogenic disturbance on the relationship between primates and their parasites is clear indication that the primatological community is taking this problem seriously (Hahn et al 2003;Chapman et al 2005;Gillespie et al 2005;Chapman et al 2006;Weyher et al 2006;Trejo-Macias et al 2007;Gillespie & Chapman 2008;Mbora & McPeek 2009;Lane et al 2011). However, truly understanding the potential impacts of anthropogenic disturbance on these relationships, or the impacts of specific parasitic organisms on their primate hosts for that matter, requires investigation of baseline epidemiological factors that naturally contribute to infection dynamics .…”

Using Parasitic Load to Measure the Effect of Anthropogenic Disturbance on Vervet Monkeys

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