What non-lethal options are available for reducing human-deer conflict, and is there evidence that they work?

As human populations grow in suburban and rural areas, conflicts with deer become increasingly common. Many communities seek nonlethal options to reduce the impacts of large deer populations on the human community. However, data for evaluating these approaches are rarely available, and it is important to understand that these methods are not aimed at reducing deer populations. Instead, the goal of these methods is to reduce the level of impact that human residents experience. The only nonlethal methods available for reducing deer populations are fertility control techniques, such as surgical sterilization and contraception. Please see our FAQ on that topic here for more information about those methods.

There are a number of techniques that can be employed to reduce the impact of deer on people:

• Reduce or eliminate deer feeding. See our FAQ on deer feeding here for information on how feeding deer contributes to human-deer conflict issues.

• Reduce deer-vehicle collisions. There are many methods that may be employed to reduce deer-vehicle collisions:

  • Reduce speed limits in deer crossing areas

  • Improve lighting along roadways to increase visibility

  • Manage habitat along roadways to improve visibility, such as cutting back tall vegetation or creating a wide border that is mowed along the sides of the road

  • Place warning signs. During rut, when deer activity is greatest, lighted temporary warning signs may be more effective than traditional permanent signs

  • Conduct education to raise awareness of the risks of deer-vehicle collisions during the rut season to increase driver caution during dawn and dusk time periods

  • Deer whistles and roadside reflectors have been found to be ineffective as methods of reducing deer-vehicle collisions

• Take steps to reduce tick-borne illness, such as Lyme Disease

  • Educate the public on tick prevention, including the use of pesticides (such as permethrin) on clothing and insect repellents (such as DEET), proper tick removal techniques, and landscaping methods to reduce ticks in yards.

  • Towns may consider spraying with pesticides to reduce ticks over large areas, or using a targeted approach, such as applying pesticide treatments to small mammals that serve as hosts to ticks in early life stages

  • Keeping rodent populations low helps to reduce Lyme Disease, as these animals are the source of infection for the ticks. See our FAQ page on Lyme Disease for more information

  • Towns may apply to the NYSDEC for a permit to employ a device called a 4-poster. 4-Posters are bait stations designed to attract deer and treat them with permethrin while while they are eating the bait. However, maintaining 4-Posters is expensive, and the constant availability of extra food for deer and other animals can also lead to many negative consequences

• Educate the public on methods for reducing plant damage

  • Enclose yards or gardens with a fence at least eight feet high

  • Place cage-type enclosures over small plants, and cover shubbery with netting

  • Electric fencing may be effective for large areas

  • Devices used to scare deer (lights, motions, sounds, sprinklers) may be effective in the short-term, but deer often learn to habituate to these devices

  • Chemical repellents applied to plants may be an effective deterrent, but they must be reapplied frequently

  • Plant species that deer do not prefer to eat (deer resistant plants). A list of deer resistant plants can be found here.

• Hazing is a method of physically harassing deer to discourage them from entering certain areas. Hazing requires a permit from the NYSDEC, and typically involves shooting at deer with nonlethal projectiles, such as rubber buckshot or beanbag rounds. Hazing works by producing a nonlethal, but intensely unpleasant experience when deer approach areas from which humans wish to exclude them. Hazing can also be done using a dog trained for this purpose, which chases deer away from the area. Hazing can be expensive and labor intensive. It must be repeated regularly to be effective, and may have the result of chasing deer out of one area and creating a new problem in a different area. The effect of hazing on deer-vehicle collisions in urban or suburban areas has not been studied (Federal Highway Administration, 2008; Honda et al., 2018).

Can we just relocate deer out of the area?

Capturing and relocating deer is often proposed by residents who seek to see deer numbers in their town reduced without harm to the deer. Studies of deer translocation (the process of capturing animals in one location and releasing them somewhere else) has been studied as a possible mechanism of alleviating human-deer conflict in residential areas. Because translocation requires that deer be captured and handled extensively, it is very stressful for them, and often results in injury or death (see our FAQ page on Capture Myopathy). A study in Cook County, Illinois, found that more than 50% of their study animals died within the first year after translocation, and many of these animals died as a result of capture stress (Jones and Witham, 1990). A study investigating the feasibility of translocation to control deer issues in a Missouri city had similar results, with low rates of survival overall, and nearly 30% of deer dying from capture myopathy. In addition, they found that the translocation process was expensive, reporting a cost of $387 per deer at the time (Beringer et al., 2002). Costs for capture have increased, and today's cost would be similar to those of contraception (see our Contraception FAQ page for more information). Moving deer to new locations also poses a risk of disease spread, and in New York State, lack of suitable habitat in which to release deer makes this method infeasible (NYSDEC, 2018). For these reasons, permits to relocate wild deer are not issued in New York State (Bishop et al., 2007).

References:

Beringer, J., L.P. Hansen, J.A. Demand, J. Sartwell, M. Wallendorf, and R. Mange. 2002. Efficacy of Translocation to Control Urban Deer in Missouri: Costs, Efficiency, and Outcome. Wildlife Society Bulletin 30(3): 767-774. Accessed at https://www.jstor.org/stable/pdf/3784230.pdf?casa_token=sH6Axv7jDswAAAAA:CYX5q3Szu6RchPLKTMP9WozE6toG0hiq1qLdUQTRFngjaaJJ7FL3NW6Py8sdSa1QupLh6RVHLT5dko1AXixMN637P-TsePsRHK5JWXN8l3iu0zaLtxop

Bishop, P., J. Glidden, M. Lowery, and D. Riehlman. 2007. A Citizen's Guide to the Management of White-tailed Deer in Urban and Suburban New York. New York State Department of Environmental Conservation, Albany, NY. Accessed at https://hamilton-ny.gov/wp-content/uploads/2018/08/NY-DEC-Citizens-Guide-to-Deer-Mgt-07.pdf

Federal Highway Administration, 2008. Wildlife-Vehicle Collision Reduction Study: Report To Congress, Chapter 6. Mitigation Methods That Seek To Influence Animal Behavior. Accessed at https://www.fhwa.dot.gov/publications/research/safety/08034/06.cfm

Honda, T., H. Iijima, and K. Uchida. 2018. A review of urban wildlife management from the animal personality perspective: The case of urban deer. Science of the Total Environment 644: 576-582. Accessed at https://www.sciencedirect.com/science/article/pii/S0048969718324112?casa_token=4uXbg0R2PHoAAAAA:DS3EpJ9UuH4SzPnGaiFZVO7OCNOUWy545Bmfycyqw-rBAAgS6WspNxsl5i_krFxX8-0TThcfBCQ#t0005

Jones, J.M. and J.H. Witham. 1990. Post-Translocation Survival and Movements of Metropolitan White-Tailed Deer. Wildlife Society Bulletin 18(4): 434-441. Accessed at https://www.jstor.org/stable/pdf/3782744.pdf?casa_token=6C_NHoZjYJgAAAAA:nNOJaf9NxKtgiGTBTEpmG7NzElu-lyOMrwLD6XFPCMkcKfBQLDxM4GeYQwVBIwCtBagB2fMt8id-6u_5vCkph_iUPqb80khyySYtgijhQFEQlBusyGDS

NYSDEC. 2018. Community Deer Management Guide. Accessed at https://www.dec.ny.gov/docs/wildlife_pdf/commdeermgmtguide.pdf.