The Electronic Guard:

A Tool in Predation

Control

The Electronic Guard helps reduce wildlife damage to

agricultural resources. Developed by the Animal and

Plant Health Inspection Services’ (APHIS) Wildlife

Services (WS) program, this device combines two

scare tactics, sound and light. Although it was created by WS’ National Wildlife Research Center (NWRC)

to protect sheep from coyote predation, the Electronic

Guard can be used to protect other livestock and

commodities from wildlife damage.

A light-sensing device activates the Electronic

Guard at nightfall and turns it off after daybreak, thus

operating the machine when predation is most likely

to occur. A timer regulates a siren and a strobe

light—sometimes just flashing the light, sometimes

just sounding the siren, and sometimes doing both at

once. This random arrangement helps keep potential

predators at bay. NWRC’s tests have shown that

using the Electronic Guard can temporarily reduce

predation an average of 80 percent in range and pasture situations and 60 percent in mountain grazing

areas.

Frightening Predators

For centuries, livestock producers have used

frightening devices to ward off potential predators.

Most predators are initially fearful of unexpected disturbances and keep their distance. Over the years,

the devices have changed from simple scarecrows

and bells or other noisemakers to more modern

devices like the Electronic Guard.

The Electronic Guard should be used only when

necessary because most predators eventually learn

to ignore the periodic light-and-sound show. This

device is not a cure-all for predation problems but is

one tool in a comprehensive approach to controlling

predator damage. It may help producers complete

the lambing season with minimal loss by stopping

predation until sheep can be moved or until other

control methods can be used.

Other Uses

A survey of users of the Electronic Guard by WS

found the device to be successful in keeping black

bears out of vineyards and white-tailed deer out of

gardens and cornfields. Customers also report that

they use the Electronic Guard to prevent damage to

haystacks and orchards by elk and deer, discourage

beavers from building dams, and frighten birds away

from commercial fish farms.

Using the Electronic Guard

The Electronic Guard should be hung from a tree

or a post on a high area near where predation has

occurred. When possible, one guard should be

placed in the center of the bedground with other

guards around the edge, especially when the bedground is near a coyote pathway.

The number of Electronic Guards needed to protect sheep will depend on the size of the pasture, the

vegetation in or around it, and the terrain. In general,

at least two units should be used in small, fenced

pastures (20–30 acres) or in level pastures with short

grass. Three or four units should be used in large,

fenced pastures (31–100 acres), hilly or wooded pastures, or those with tall grass. In open-range conditions, the number of Electronic Guards depends on

the number of sheep and the size of the bedground.

NWRC testing shows that at least 4 guards should

be used with a band of 1,000 ewes and their lambs.

How to Order

The WS program manufactures the Electronic

Guard, which is a self-contained, 11-pound cylinder

that can operate for approximately 60 days on a 12-

volt alkaline battery. The Electronic Guard costs

about $250, not including the battery, and can be

ordered through your State APHIS WS office listed in

the blue pages of most telephone books under “U.S.

Department of Agriculture.” The device also may be

obtained directly from WS’ Pocatello Supply Depot,

238 E. Dillon St., Pocatello, ID 83201. Each unit is

shipped with a complete set of instructions.

Additional Information

You may obtain further information about WS

from any State APHIS WS office. For the address

and telephone number of the office in your area, call

the WS Operational Support Staff at (301) 734-7921.

You can also find information on WS programs by visiting the Web site at http://www.aphis.usda.gov/ws.

Factsheet

Wildlife Services January 2002

APHIS
United States Department of Agriculture • Animal and Plant Health Inspection Service • Safeguarding American Agriculture

The U.S. Department of Agriculture (USDA) prohibits discrimination

in all its programs and activities on the basis of race, color, national

origin, sex, religion, age, disability, political beliefs, sexual orientation, or marital or family status. (Not all prohibited bases apply to

all programs.) Persons with disabilities who require alternative

means for communication of program information (Braille, large

print, audiotape, etc.) should contact USDA’s TARGET Center at

(202) 720–2600 (voice and TDD).

To file a complaint of discrimination, write USDA, Director, Office of

Civil Rights, Room 326–W, Whitten Building, 1400 Independence

Avenue, SW, Washington, DC 20250–9410 or call (202) 720–5964

(voice and TDD). USDA is an equal opportunity provider and

employer.