Differential response of jaguars (Panthera onca) and pumas (Puma concolor) to anthropogenic landscape transformations

DE ANGELO, CARLOS; PAVIOLO, AGUSTÍN; DI BITETTI, MARIO

Mendoza, Argentina

Congreso; 10th International Mammalogical Congress; 2009

CCT CONICET Mendoza (CRICYT), CONICET, IADIZA, GiB, International Federation of Mammalogists, SAREM

Jaguars and pumas are the largest felids of the American continent. They are similar in size and behavior, but pumas show larger distribution range and appear to be more resilient to human impacts. Our objective was to compare the response of both species to landscape characteristics in a highly modified environment, the Upper Parana Atlantic Forest, where both species had continuous distribution in the past. We used presence-only data collected through a monitoring program between 2002-2008 along the study area (106 jaguar and 241 puma points). Using Ecological Niche Factor Analysis (ENFA) and discriminant analysis, we characterized species-specific habitat requirements, built habitat suitability maps and examined interspecific differences in niche parameters related with landscape characteristics. Both species showed high dependence on native forest and habitat protection, and avoided highly modified environments and areas more accessible to humans. However, jaguars showed higher differences between their optimal habitat and the available landscape (ENFA-Marginality M=2.584) and lower tolerance to deviations from their optimal habitat (ENFATolerance T=0.644) than pumas (M=1.749; T=0.833). Though their niches highly overlapped (Pianka´s O=0.751), pumas presented a broader niche (std Levins´ index: puma B*=0.681; jaguar B*=0.544) that resulted in a larger area suitable for pumas. All jaguar suitable areas were also suitable for pumas; however 54% of puma suitable habitat, characterized by higher fragmentation and less protection, was unsuitable for jaguars. Our results support the hypothesis of higher puma adaptability to human-altered environments. It has been suggested that this adaptability is related to puma’s ability to survive on smaller and more diverse prey species than jaguars, but their differences in life history patterns and relationship with humans are probably also influencing their differential response. This difference may explain why pumas are now the only large cats in vast portions of a previously shared range in the Americas.