Top predator ecology and conservation: Lesson from jaguars in southeastern Mexico

Ecology of large felids and their prey in small reserves of the Yucatán Peninsula of Mexico

Jaguars and pumas are top-predator species in the Neotropics that are threatened by habitat destruction, illegal poaching of their body parts and their favored prey, and by the human-wildlife conflicts that arise when predators attack livestock. Much of the remaining felid habitat in the Americas is in protected nature reserves that are too small and isolated to support local populations. Surrounding forests therefore play a vital role in felid conservation. Successful long-term conservation of these two felids requires evidence-based knowledge of their biological and ecological requirements. We studied population distributions of jaguars and pumas and their prey in and between two small, private reserves of the Northern Yucatán Peninsula, Mexico, with areas of 25 and 43 km². During 2 years of camera trapping (2015 and 2016), we detected 21 jaguars, from which we estimated an average space requirement of 28-45 km²/individual. Dietary niche overlap exceeded random expectation. The most frequently occurring prey items in jaguar and puma diets were collared peccary and deer. Jaguar also favored nine-banded armadillos and white-nosed coati, while puma favored canids. Both felids avoided ocellated turkey. Overall, diet of jaguars was less species-rich, but similar in niche breadth, to that of pumas. A fluid use of space by both species, in 2015 tending toward mutual attraction and in 2016 toward partial exclusion of pumas by jaguars, combined with the high dietary overlap, is consistent with a dominance hierarchy facilitating coexistence. Jaguars and pumas favor the same prey as the people in local communities who hunt, which likely will intensify human-wildlife impacts when prey become scarce. We conclude that even small reserves play an important role in increasing the continuity of habitat for prey and large felids, whose generalist habits suppress interspecific competition for increasingly limiting prey that are largely shared between them and humans.

Spatial distribution patterns of tick community structure in sympatric jaguars (Panthera onca) and pumas (Puma concolor) from three ecoregions in Mexico

We examined tick communities on wild felid hosts in three ecoregions of Mexico. We collected 186 ticks of 7 species from 10 pumas (Puma concolor) and 9 jaguars (Panthera onca). Tick community composition varied across the ecoregions, and across host species within each region. Overall, Ixodes affinis, Amblyomma ovale, and Amblyomma tenellum were the most abundant species; however, only the latter two ticks were distributed across all three ecoregions, while I. affinis, along with Ixodes spinipalpis, Amblyomma inornatum, and Amblyomma parvum were restricted to more limited geographical regions. Ixodes affinis occurred strictly in southern tropical rainforest ecoregions and was significantly more abundant in Selva Lacandona compared with the Yucatán Peninsula. Amblyomma ovale was significantly more common in the tropical dry forest in the Pacific coastal ecoregion. Amblyomma tenellum abundance tended to be higher on jaguars, while I. affinis abundance was higher on pumas. Regional distribution patterns of some tick species (e.g., I. affinis and I. spinipalpis) may be determined by off-host environmental conditions rather than host factors. In contrast, at the local scale, occurrence and abundance of some tick species (e.g., A. tenellum, A. ovale and Rhipicephalus microplus) might be driven by ecological-host factors, such as habitat use or predator-prey relationships.

Jaguar (Panthera onca) spatial ecology outside protected areas in the Selva Maya

Jaguars (Panthera onca) are endangered in several countries and a priority species for conservation action. Despite extensive research efforts in Mexico most studies have been associated with natural protected areas far from human habitation. Because protected areas are too few to conserve the jaguar population over the long–term, a landscape approach that includes both protected and unprotected lands is needed. This is the case in Quintana Roo State where an ecological corridor linking two protected areas (Yum Balam and Sian Ka'an) is at risk of disappearing due to tourism–driven activities. Between 2013 and 2015, four male jaguars were captured and monitored using satellite telemetry inside the corridor. The mean home range size (± SD) was 101.5 km2 (± 75.9 km2) for the dry season and 172 km2 (± 107.29 km2) for the rainy season. The mean core area size (± SD) was 17.54 km2 (± 16.21 km2) for the dry season and 29.07 km2 (± 16.19 km2) for the rainy season. No significant seasonal differences were found for home ranges or for core areas. As expected, we observed that jaguars preferred forest or young secondary growth over profusely disturbed areas, using whatever vegetation was available in their home ranges. Although it is not protected, a biological corridor linking Yum Balam and Sian Ka'an still holds its own jaguar population, a population that has learned to coexist with human presence. Conservation actions are recommended at landscape level to maintain what remains of tropical mature forest and to promote the development of long–term secondary growth into close tree canopy