Impact of seasonal flooding on Jaguar (Panthera onca) home range and movements

Movement is an integral part of animal foraging and survival. Thus, conditions that hamper animal movement should cause significant shifts in their ecology, especially in traits directly related to movement such as home range, displacement, and site fidelity. Using jaguars (Panthera onca) as our model species, we measured the effect of reduced mobility in a unique natural experiment. The Amazonian varzeas of the Mamirauá Reserve have such a prevalent and intense flooding that jaguars in the region adopt a semiaquatic and arboreal lifestyle during the wet season. We hypothesized that Jaguar space use would change substantially between seasons with decreasing home ranges, core areas, and displacements during the high-water periods. Given previously documented sex-based differences in Jaguar space use and movement we also evaluated sex-based differences in movement parameters in our study system. We measured seasonal home ranges and core areas using autocorrelated kernel density estimation, with the 95% contour for home ranges and 50% for core areas. Displacement was calculated as the velocity of movement in meters per second in each given step comprised of locations every 6 h. Our results indicated that home range area remained constant between seasons, but displacement decreased during high-water periods as expected. We discuss the possibility that jaguars switch to an ambushing form of predation, which is made possible by the large number of prey in the region. This ambushing tactic would allow jaguars to retain a large home range despite low mobility and larger movement costs.