Breaking the human shield: Predator habituation may reduce human effects
on predator-prey dynamics
Abstract
While many species are fearful of human presence, others may habituate
after prolonged, non-lethal exposure. Highly persecuted carnivores often
take longer to habituate than herbivores, which can lead to prey
associating with humans to ‘shield’ themselves from predators. We
conducted an experiment in a hyper-diverse African reserve to examine
how an apex predator (spotted hyena) and two primary prey species
partition spatiotemporal activity in response to 1) threatening human
voice playbacks and 2) long-term, less-threatening tourism activity.
Hyenas avoided areas with human voice playbacks during the day, allowing
prey to use these areas diurnally to shield themselves from predation.
Neither predator nor prey were deterred from sites with tourists. This
apparent habituation by predators conserved co-occurrence between
predators and their prey, ‘breaking’ the human shield. While use of
human shields may be widespread among large mammalian predators and
prey, these effects may lessen through time in the absence of predator
persecution.