Quirks & Quarks

Restoring ecosystems with fear

Creating fear of predators - even if the predators aren't real - is effective in discouraging prey from overexploiting their ecosystem.

Fear of predators keeps prey under control

Raccoon foraging on a beach (S. Baker/Western University)
Humans have altered many landscapes by removing large predators, like wolves and cougars, and the result is a boom in the population of the animals they used to prey on - such as deer and raccoons.

In new work, Dr. Liana Zanette, a biologist from Western University in London, Ontario, has tested whether or not it is possible that just the fear of these predators - rather than the presence of the predators themselves - could be used to control overpopulated wildlife.

In an attempt to drive raccoons off beaches in the Gulf Islands, where they were ravaging the intertidal ecosystem, she and her colleagues used the sounds of barking dogs. The raccoons either ran, or reduced their foraging because of increased wariness, which allowed the intertidal animals to recover.

Related Links

Paper in Nature Communications
- Western University release
- University of Victoria release
CBC News story
- Hakai Magazine story
- The Atlantic story