SRU installs deer exclosures to educate people about the effects of overgrazing in forests

Oct. 1, 2024

SLIPPERY ROCK, Pa. - Imagine a world without deer. Organizers of a project at Slippery Rock University are providing students and the public a glimpse, albeit in two small, fenced-off sections of forest on campus known as "deer exclosures."

With an estimated population of more than 1.5 million deer in Pennsylvania, or 30 per square mile, the official state animal has well-trodden people's attention on roadways and in backyards, but less so deeper in the woods.

"Everybody knows there are too many deer in Pennsylvania, but to visually see what they're doing can make a big impact," said Dean DeNicola, professor of biology. "For my classes we would go sample vegetation inside and outside of deer exclosures and measure the effects deer have on Pennsylvania forests."

Until this year, the only deer exlosures near Slippery Rock were at Jennings Environmental Education Center. But now, thanks to a University grant, there are two deer exclosures at SRU's Macoskey Center for Sustainability Education and Research. The two 40-by-40-foot exclosures with eight-foot-high fences are located near the hiking trails on the Macoskey Center's 70-acre grounds.

The exclosures provide public demonstrations and more educational activities for students concerning the effects of overgrazing by deer in Pennsylvania forests. Deer eat most of the understory trees and shrubs, aside from a few ferns and other plants that have thorns or chemical defenses.

"That's a big concern because any new trees that are sprouting are going to replace those old trees, but they are just getting grazed down by the deer," DeNicola said. "Without new trees that has an ecological effect on maintaining a healthy forest."

According to researchers, the deer population is three times as dense as it was prior to the 1800s and overgrazing by deer over the last 50 years has greatly affected plant biodiversity, forest regeneration, invasive species prevalence, and public health because of vector-borne diseases such as Lyme Disease.

The deer exclosures will be used for student lab activities with outcomes involving analyzing vegetation density and diversity, invasive plant species distribution, soil, microclimate and animal populations. Organizers of the project anticipate more than 300 students visiting the exclosures as part of lab exercises each year from multiple disciplines.

Students outside of a class activities or the general public are encouraged to contribute to research by taking photos at the deer exclosures, as instructed on an interpretive sign at each location and emailing them to the Macoskey Center at [email protected]. The two exclosures are located just off the Blue Bird Hiking Trail about a half mile away from Macoskey Center.

"This is a great citizen science effort where anyone can help us, because students in a biology class can't be out there every day or for every season," said Sami Bortz, manager of the Macoskey Center. "People can participate in our data collection to identify what the vegetative states look like inside the exclosure versus outside of the exclosure. We are hoping to gather a visual representation of what it looks like over time. We might see other native species of plants become more dominant."

The project was funded by SRU's Green Fund, which funds environmentally friendly projects and programs on campus.

More information about the Green Fund is available on the Sustainability section of the website. More information about the Macoskey Center is also available on the University website.

MEDIA CONTACT: Justin Zackal | 724.738.4854 |  [email protected]