Understanding how predators and their prey coexist in space and time is a core interest in ecology. Vast amounts of photographic detection data are now available from a growing number of camera-trap studies worldwide. These data boost our ability to study an elusive yet important topic in ecology: species interactions in space and time. Here, we investigated the spatiotemporal configuration of the activity of a typically nocturnal and crepuscular predator and a diurnal prey in protected areas. We explored whether agoutis (Dasyprocta leporina) respond to predation risks by adjusting the timing of activity to the occurrence and timing of activity of its potential predator, the ocelot (Leopardus pardalis) and whether the ocelot's occurrence responds to that of the prey. Using a custom Bayesian occupancy model for two species, we analysed camera-trap data collected over three protected tropical forests from Brazil and Suriname (2 to 9 years). Our model distinguishes between occupancy (i.e. spatial distribution) and detection (i.e. activity in space and time). We detected a positive spatial association between predator and prey, suggesting that ocelots seek places where agoutis are present. Instead of segregating in space, agoutis appeared to respond to increased predation risk by reduced activity. The most pronounced reduction in agouti activity (i.e. probability of detection) was during twilight in sites where ocelots occurred. Our results illustrate how jointly modelling interactions in both space and time informs our understanding of predator-prey coexistence.
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