Landscape structure and composition define the body condition of dung beetles (Coleoptera: Scarabaeinae) in a fragmented tropical rainforest

Environmental disturbance generates changes in local abiotic and biotic conditions, which affect the physiological condition of the organisms. However, most of the studies dealing with environmental disturbance have focused only on species diversity, and often ignore the species' health to evaluate habitat quality. Recently, through tools that evaluate the body condition of individuals, some studies have demonstrated that it is possible to know how species respond to environmental changes. In this study, we evaluated the effect of local and landscape parameters on different indicators of body condition and abundance of three dung beetle species in a fragmented Tropical rainforest in Mexico. We measured beetle's body size and three indicators of physiological condition (body dry mass, lipid and muscle mass) in 15 sites with different vegetation configuration. In general, abundance, body size and physiological condition of all species were sensitive to different landscape features. Onthophagus rhinolophus, a species typically found in conserved forest, unexpectedly showed a positive relation of body condition with landscape diversity and amount of edge, and the presence of altered sites remnants favored its body dry mass, muscle mass and body size. Nevertheless, Onthophagus batesi and Canthon cyanellus, mostly found in disturbed areas, exhibited better body condition when there were conserved habitats nearby. Therefore, we showed that O. rhinolophus is a sensitive species supporting reduced levels of habitat disturbance, while O. batesi and C. cyanellus are tolerant species that need conserved forests nearby. We highlight the importance of understanding the effect of environmental disturbance on the species' body condition in order to maintain not only abundant, but also healthy populations of wild animals in fragmented forests.