Counting Deer at Arkansas Post National Memorial: White-Tailed Deer Monitoring, 2005–2022

White-tailed deer are among the most charismatic animals at Arkansas Post National Memorial — and they were nearly extinct in the early 1900s, from overhunting and forest clearing. Hunting rules and the loss of most of their natural predators have since let deer populations grow as never before.

White-tailed deer at Arkansas Post National Memorial. NPS.

Why too many deer is a problem

• Without predators, deer can overpopulate and die of disease and starvation.
• Overbrowsing harms trees and other plants. Deer prefer native plants, which lets exotic, invasive plants spread.
• More deer mean more deer–vehicle collisions, and deer spread ticks that carry human diseases.

Crowded herds are prone to hemorrhagic disease and chronic wasting disease. Hemorrhagic disease can kill 50% or more of a herd each year, for several years; one form isn't known to infect people or livestock, but the other can make domestic sheep severely ill and die. Deer also carry ticks infected with Lyme disease, Rocky Mountain spotted fever and ehrlichiosis from place to place. Keeping deer numbers in check protects deer, people and other animals.

How they are counted

Scientists from the NPS Heartland Inventory and Monitoring Network have monitored the memorial's deer since 2005, to track yearly changes and long-term trends and to map where deer are. Every winter, from January to mid-March, they drive the park's two main tour roads at night and count deer with bright spotlights.

The counts help the park judge the restoration of its cultural landscapes — an important part of managing the memorial — and the safety risks from disease and collisions.

Deer per square kilometer surveyed in the park (solid line, with 95% confidence bars) and deer harvested in Arkansas County from the 2009/2010 hunting season (dashed line). The trend line is not significant. NPS.

What they found, 2005–2022

• After two years of decline, the population rose seven-fold from 2007 to 2011.
• It fell for six years, 2011–2017, then tripled from 2017 to 2019.
• It has been declining again since 2019.
• Density ranged from about 17 deer per square kilometer in 2007 to just under 119 in 2011.
• Overall, the population fell 0.4% a year, but that trend is not statistically significant — more data are needed to know whether it is really changing.

Where deer were seen each year, with counts adjusted for the area surveyed: the most in 2005, 2008, 2010–2012 and 2019–2020, the fewest in 2007, 2016 and 2017. NPS.

White-tailed deer browsing at the forest edge. NPS.

More: the full report.

Sources

Based on "Deer Monitoring at Arkansas Post National Memorial," National Park Service, Heartland Inventory and Monitoring Network; a work of the United States government in the public domain.