Oh, Deer! Population Control

By Carole A. Barth

Every deer population control method has its share of controversy. And yet, without population control, the deer and the forest will both continue to suffer. Here is a brief description of the currently available methods of population control, the issues pertaining to each, and their effectiveness.

Managed Hunts. Managed hunts are not like traditional hunting seasons. To begin with, these hunts are not open to all hunters. Participants must pass a pre-screening questionnaire and a background check. Hunters also have to have a State Shooter Qualification Card demonstrating his/her proficiency with the firearm they plan to use for the hunting program. Further, the process is supervised by wildlife experts and police. Safety buffers are established and the hunting sites are selected so hunters are generally firing down. Some hunts use rifles, others use bows. Bows are generally considered safer, since an arrow will not ricochet and cannot penetrate a house like a bullet can.

Issues: These hunts are deplored by those who believe all hunting is inhumane. Others are concerned that volunteer hunters may not be skilled enough to effect a quick, painless kill.

Effectiveness: One problem is that most sport hunters still target trophy bucks. However, to effectively manage the population, does should be targeted.
Sharpshooters. Instead of hunters, these programs use police or other trained marksmen. Bait is used to draw the deer into position, and high-powered scopes allow for precise shot placement to the head or neck. Death comes within 30 seconds or less. It is more execution than hunt. Specialized ammunition is used to increase safety, and sharpshooter programs are generally considered to be the safer approach for areas near dense human population centers. Meat from deer killed in these programs is donated to area food banks.

Issues: These hunts are deplored by those who believe all hunting is inhumane.

Effectiveness: This approach is considered the most cost-effective by many localities.
Reintroduction of Predators. Predators like wolves did more than simply keep deer numbers in check. By culling the sick or weak animals, predators keep the herd healthy. Moreover, predator and prey population levels are linked in a feedback loop; keeping numbers balanced with what the habitat will support.

Issues: In some states, where wolves have been reintroduced or where the suburbs have begun to encroach on mountain lion habitat, conflicts arise when farmers or residents blame predators for the loss of livestock or pets.

Effectiveness: It is difficult to reintroduce large predators, such as the mountain lion, into remnant habitat fragments. This technique clearly has more potential in wilderness areas than in urban and suburban communities. Wolves, for example, have been successfully reintroduced in a number of wilderness areas. However, there is data to show that wolves can also adapt to more open, less wild areas.
Contraception and Contragestation. A variety of contraceptives and delivery methods are being tested, some at the National Institute of Standards. Contragestation is the process in which the development of a fetus is purposely terminated. This can be done by applying a drug called prostaglandin to bait piles in the winter.

Issues: No one knows what the impact would be of the wide-scale release of contraceptive drugs into the environment through wildlife. There is concern that these substances might affect non-target species or end up contaminating the environment. Contragestation programs may be culturally unacceptable and people may object to finding deer fetuses in urban areas.

Effectiveness: Contraception works best on confined populations, where one can be reasonably sure that the deer have been treated consistently. (Depending on the drug involved, treatments must be repeated at least every two years.) Managers also need a way to tell which deer have been treated. Where individuals roam widely, this is very difficult.
Population Control in Montgomery County. The Montgomery County Deer Management Workgroup consists of members from the Maryland Department of Natural Resources (Wildlife and Heritage Service), M-NCPPC (Montgomery County Department of Parks), Montgomery County Cooperative Extension Services, Montgomery County Police Department, U.S. Geological Survey’s Biological Services Division (Patuxent Wildlife Research Station), U.S. National Park Service, and Washington Suburban Sanitary Commission. This group developed a deer management plan for the County and implements a countywide deer management program. The group annually reviews deer data and makes recommendations to agencies and private landowners.

Currently, Montgomery County Parks Departments uses both managed hunts and sharpshooters to control deer. Managed hunts were implemented in the County in the Fall of 1996 and have occurred annually ever since. Currently, managed hunts are being conducted in eight County parks annually:

Hoyles Mill Conservation Park,
Blockhouse Point Conservation Park,
Woodstock Equestrian Park,
North Germantown Greenway,
Great Seneca Stream Valley Park,
Rachel Carson Conservation Park,
Buck Lodge Forest Conservation Park, and
Little Bennett Regional Park.

Police-based sharpshooting was implemented in the County in the spring of 1999 and has occurred annually ever since.

To date, the Department has conducted police-based sharpshooting programs in ten County parks:

Agricultural History Farm Park and attached segments of Rock Creek Stream Valley Park (Derwood),
Black Hill Regional Park (Boyds),
Layhill Local Park (Wheaton),
North Branch Stream Valley Park, Units 2&3 (Norbeck),
Nortwest Branch Recreation Park (Aspen Hill),
Northwest Branch Stream Valley Park, Unit 7 (Ashton),
Rock Creek Regional Park (Rockville),
Rock Creek Stream Valley Park, Unit 7 (Aspen Hill),
Wheaton Regional Park (Wheaton), and
Woodlawn Special Park (Sandy Spring).

Together these programs cover about 40 percent of the County’s Parks. There are additional areas where management has been recommended, but funding is not available for expanding the program. (For more information on deer management in the County, see the following webpage: www.montgomeryparks.org/ caring-for-our-parks/wildlife/deer-management.) [Note: This URL has been updated since the printing of the newsletter.]

While I was able to find reports on the number of deer harvested each year by these programs, I could not find anything showing the change in deer density over time. Nor could I find anything comparing current density figures to the deer density goals. Without this information, it is hard to objectively say what impact the program is having. Similarly, reports mention improvements in vegetation, such as the return of orchids and lilies to some areas, but I could find no actual data. Without data, there is no way to quantify this improvement. ■

Read Part 1: The Reasons Behind All The Deer Read Part 2: Deer Repellent