By Alison Mitchell
Executive director, New Jersey Conservation Foundation
Deer are pretty much everywhere in New Jersey. At first glance, their abundance might seem harmless, even welcome. But their numbers are fueling a complex and urgent ecological crisis that threatens our native forests and wildlife, as well as public health and safety.
In many places in the state where deer populations are 10 times above healthy levels, the forests have tragically lost their natural diversity and vitality. This is not the fault of the animals themselves: They are responding to a landscape profoundly changed by human activity.
After unregulated commercial hunting was banned in New Jersey in the late 1800s, deer populations rebounded. Humans had already eliminated their largest natural predators. Agriculture and suburban development began to carve up forests, creating ideal habitat for deer which flourish at the edge of the woods. A greater abundance of food and lack of wild predators, coupled with limited hunting opportunities in populated areas and milder winters, led to a surge in deer numbers.
“It’s a perfect storm,” says Jay Kelly, a biology professor at Raritan Valley Community College, who for decades has been documenting the negative impacts on forests caused by overabundant deer.
Deer are a cherished part of New Jersey’s landscape, and we are lucky to have them in our midst. But their numbers are way out of balance with the rest of our natural world. As a result, they are causing serious damage to the ecosystem. Woody native tree seedlings (such as oaks and hickories) and beautiful shrubs (like dogwoods) disappear under heavy browsing in the winter, and invasive species that aren’t appealing to deer outcompete natives that try to regenerate.
“Deer populations have been far higher than forests can handle for almost 50 years now in New Jersey,” Kelly explains. “They are decimating the landscape.”
As a result, we are losing other cherished wild animals. With the loss of native vegetation, forest songbirds lose both shrubs as safe nesting sites and the native insect food supply that their nestlings depend upon. Amphibians that depend on the forest understory also begin to decline. Essential pollinators such as butterflies and moths struggle as their wild host plants vanish, adding to further ecosystem decline.
In short, overabundant deer populations create a sad fate for countless other creatures.
Although the need for action is clear, addressing deer overpopulation can be controversial. Deer have walked this planet for millions of years and evoke deep affection and admiration. Yet, we have a responsibility to protect forests and other wildlife, and to ensure the long-term health of deer themselves. Due to overcrowded populations, more deer suffer when diseases like blue tongue emerge on the scene.
Beyond ecological damage, overabundant deer populations pose more direct risks to humans too. Deer-vehicle collisions cause thousands of injuries, with an estimated 25,000 vehicle collisions involving deer in New Jersey every year. These incidents also result in harm to the deer themselves, which are often left injured along roadsides.
High deer populations contribute to the spread of Lyme and other tick-borne diseases. There are also significant impacts to agriculture, with 25% of New Jersey farmers surveyed reporting that they’ve abandoned a parcel of tillable land due to excessive deer damage, and 36% saying they’ve stopped growing their preferred crops for the same reason.
We owe it to our forests, our communities, and future generations to address the problems we’ve created for New Jersey’s wildlife and their habitats. But it’s not easy to address the overpopulation of a wonderful animal, and we need to keep both compassion and a commitment to stewardship foremost in our thinking.
