Responses of Small Mammals to Predator Odors in the Field

Abstract

While we are asleep, forests, meadows, and fields teem with nocturnal mammals. Dramatic scenes of predation take place, all unseen by humans. In this exercise, we will learn how to indirectly record such nocturnal interactions between predator and prey.

Mammalian predators possess keen senses of smell and hearing, ensuring their meals. The prey animals, on the other hand, are adept at detecting and avoiding predators. Again, olfaction plays an important role in this survival mechanism.

Although prey species must coexist with predators, they reduce predation risk by monitoring whereabouts and activity of their main predators and avoiding them to the greatest extent possible in both space and time. Most small mammals rely on olfaction to detect and avoid predators. They can smell mammalian predators such as wolves, coyotes, foxes, cats, or mustelids directly, or extract information about time and place of their activities from predator sign such as droppings, urine, scent marks with secretions from skin glands, tracks, rubs, or scrapings. Rodents can distinguish the odors of different carnivore species. Herbivorous prey species tend to respond more strongly to the odors of sympatric predators than to those of allopatric carnivores (Müller-Schwarze 1972).