ANIMAL AND PLANT HEALTH INSPECTION SERVICE

Avian influenza viruses and other pathogens that impact domestic poultry often 

cause little or no illness in wildlife. For this reason, apparently healthy wild birds 

and mammals could spread disease onto farms when they are attracted to areas 

with abundant food, water, and/or shelter.

You can build on and enhance your farm biosecurity by putting wildlife 

management practices in place. There are several nonlethal ways to make 

farms less welcoming to wildlife. 

Wild birds and mammals visit barns, silos, and other structures at farms and 

poultry facilities to nest, rest, or seek shelter. The practices below can help you 

stop wildlife from nesting and living in and near your poultry facilities, and 

coming into direct contact with your poultry. Keeping wildlife away from your 

farm also helps you avoid accidentally transporting wildlife fecal material and 

secretions into your facilities on boots, equipment, and food. 

Inspecting Structures

The design of some poultry facilities may help to attract or deter wildlife. For 

instance, structures with shorter or no eave overhangs are less likely to attract 

nesting birds. Structures with top-vein ventilation, roof-top vents, and overhead 

wires may attract perching birds—allowing their feces to drop near or directly 

onto the barn floor. You can easily spot problem areas by looking for 

whitewash from bird fecal material on the ground below eaves or on rafters.

Take time to inspect your facilities and look for design elements that may 

attract wildlife. Biologists with Wildlife Services, a program within the U.S. 

Department of Agriculture’s (USDA) Animal and Plant Health Inspection 

Service, can help you conduct an onsite assessment.

Plugging Holes and Burrows

Plug and patch holes in building exteriors to prevent rodents and wild birds 

such as European starlings from using them for nesting or shelter. Also, check 

all screens and door openings regularly and repair or replace them when 

damaged to prevent wildlife from entering your facilities.

Concrete aprons around building side walls can deter rodents, cottontail 

rabbits, and other small mammals from burrowing into buildings. Fill small 

burrows, tunnels, and other holes around structures with gravel. 

Improving Biosecurity With

Wildlife Management Practices: 

Preventing Access to Barns and Other Facilities

There are several nonlethal 

management methods for 

reducing wildlife’s potential 

spread of disease on farms.
ANIMAL AND PLANT HEALTH INSPECTION SERVICE

USDA is an equal opportunity provider, 

employer, and lender.

Program Aid No. 2210 ● Issued October 2016

Installing Barriers, Netting, and Other Deterrents

Wild birds often use ledges, rafters, and eaves as roosting and nesting sites. 

Install barriers or other deterrents, such as repellent gel or bird spikes, to 

these areas. 

Nylon netting or wire mesh should be tightly secured on all sides and regularly 

inspected for holes and wear. Ten- or 12-gauge mesh with 1-inch openings will 

exclude most bird species if it’s properly installed and maintained. If it’s 

improperly installed and maintained, exclusion netting can actually benefit 

nesting birds by forming small pockets that protect their nests from predators, 

so be sure to inspect it regularly. 

Before nesting season begins, remember to wash away or remove old nests per 

Federal and State regulations. If their nests were successful, birds often return 

to the same nesting location year after year. Farm managers can consult with 

local, State, or Federal biologists to learn more about the wildlife nesting period 

in their area. Please note that it is unlawful to remove native wild bird nests 

with eggs or young in them.

Recommended Actions

• Conduct a wildlife assessment at your farm. Do wild animals have access 

to food, water, and shelter on your site? If so, learn about and use wildlife 

management methods to improve your biosecurity.

• Inspect your buildings and other structures regularly for holes, tears, and 

other openings that would allow wildlife access to poultry or poultry feed 

and equipment. 

• Prevent wild birds and other wildlife from nesting, roosting, and living in 

or near your poultry facilities by plugging and patching holes and installing 

barriers and deterrents.

• Do not walk or drive trucks, tractors, or other equipment through areas 

where waterfowl or other wildlife fecal material may be present. 

Please note that the lethal removal of native wildlife is regulated under Federal and 

State laws. USDA and other experts do not recommend lethally removing native wild 

birds to prevent the spread of highly pathogenic avian influenza or other diseases. 

Because wild birds are abundant and constantly moving, using lethal methods is 

not practical or environmentally sound. It is much more effective to remove 

sources of wildlife attraction than to manage wild animals after they have arrived 

on your property.

Learn More

If you have specific questions about wildlife management on your farm or need 

help conducting a wildlife assessment, call your nearest USDA Wildlife Services 

office toll free at 1-866-4USDA-WS (1-866-487-3297). 

For general information on avian influenza and emergency response, go to 

www.aphis.usda.gov/animal-health/aiupdates.