Foraging deer help (not hinder) diversity.

• Position: Ecosystems

Reducing the number of deer in forests and parks may reduce the number of reptiles, amphibians, and insects in that area, suggests research from Ohio State University, Columbus, and the National Park Service, Washington, D.C., which found that higher deer activity is modifying forest ecosystems in unexpected ways. Out of several species of snakes, salamanders, and invertebrates studied, a greater diversity of animals was found in areas with deer populations than in areas with no deer activity.

The study--which comes at a time when many states have begun to control deer populations selectively--challenges previous research that has suggested deer can impact forest ecosystems negatively through eating plants that many smaller animals may depend on.

Instead, researchers found that high numbers of deer may, in tact, be attracting a greater number of species. This may be because their waste creates a more nutrient-rich soil and, as a result, areas with deer draw higher numbers of insects and other invertebrates. These insects then attract larger predators that thrive on insect larva, such as salamanders, and the salamanders in turn attract even larger predators, such as snakes. "By just reducing the number of deer, we're actually impacting forest ecosystems without even knowing the possible effects," asserts Katherine Greenwald, coauthor of the study and doctoral student...