For decades, land owners and managers have combined corn with cameras in order to estimate their deer population—the corn lures the animals and the cameras offer a glimpse of the total population.
But a recent study conducted by a University of Georgia graduate student shines a light on the inaccuracies prevalent in this deer management method, which could mean good news for both deer hunters and landowners.
James Johnson, a doctoral student in wildlife management at the UGA Warnell School of Forestry and Natural Resources, said “baited camera surveys,” a method of using corn to lure deer to an area where an automated camera photographs them, are a popular way for landowners to gauge their overall deer population. This information is used in making decisions about habitat management, quotas allowed during hunting season and the overall health of the population.
But the offering of food can throw off the numbers, said Johnson, who analyzed three different methods of surveying deer populations and gathered nearly 1 million wildlife photos over a three-year period.
In his study, which was funded in part by the Georgia Department of Natural Resources, Johnson compared the baiting method—also called the Jacobson Method—with sampling methods using unmarked infrared cameras as well as an approach that involved putting tracking collars on 25 deer and noting their movements in a particular area.
Of the three methods, Johnson said, the baiting method noted the largest deer population—but these numbers were inconsistent with populations estimated from the other two methods.
“Baiting can alter movement patterns and affect hunter harvest rates,” said Johnson, noting that this method also assumes that the deer who come to the cameras to eat are coming at equal rates for males and females. But this is inaccurate, as female deer have smaller roaming areas and are more likely to visit certain cameras more often.
“An unmarked and unbaited camera survey simplifies data collection, reduces costs and allows for more accurate estimates,” he added.
Having an accurate method to measure deer population is critical throughout Georgia and the United States. These numbers help inform how the land is managed, how habitat may be affected, and how many deer might be appropriately hunted in that area.
Johnson is now working on developing an app for forest owners and managers that would allow them to upload deer data taken from non-baited cameras, apply it to an equation and give them real-time updates on their deer population. This kind of technology could also benefit Georgia DNR and other wildlife agencies looking to keep tabs on deer population trends.
“I think we’re getting there,” Johnson added. “That’s my goal over the next two years; these baited surveys aren’t fully representing what the numbers are.”