Clifford E. & Melda C. Snyder Research and Extension Farm
Wildlife Damage: Bear

Education Programs > Wildlife Damage Guide

Wildlife Damage | Geese | Deer | Other Wildlife

Other Wildlife

In addition to Canada Geese and White-Tailed Deer, other kinds of wildlife may be of concern regarding economic damage to property, agriculture and natural resources. Regulations and policies for dealing with these issues may change. When confronted with damage you believe is due to wildlife such as wild turkey, blackbird, or bear, the best course of action is to contact New Jersey Division of Fish & Wildlife.


Blackbirds cause severe damage to a variety of agricultural crops, including sunflowers, rice, corn, winter wheat, fruits, and nuts. Field crops are especially vulnerable to bird damage as they serve as a “buffet” for migrating birds providing a high-energy, relatively easy food source.

Sunflower and rice crops are a favorite of blackbirds, sustaining yearly losses of $5–13 million. Discouraging blackbirds from foraging in favored sunflower fields is difficult; however, repellents can be effective if alternative foraging sites are readily available. NWRC scientists recently completed efficacy studies in which blackbirds were offered oilseed and confectionary sunflower treated with ananthraquinone-based repellent. Compared to untreated field sites, scientists observed less sunflower damage and more sunflower yield within confectionary sunflower fields treated with the repellent. Though the anthraquinone-based repellent proved effective, additional field studies are needed to identify practical and effective methods for applying the repellent to ripening sunflower heads.

Other successful NWRC methods for reducing blackbird damage include the application of a registered cattail herbicide to reduce blackbird roosting sites and the establishment of wildlife conservation sunflower plots. Cattail marshes located next to sunflower fields create perfect roosting sites for blackbirds. By thinning select marshes with the herbicide glyphosate, WS biologists make these roosts less attractive, thus dispersing large concentrations of blackbirds away from sunflower production areas.

Wildlife conservation sunflower plots (or lure crops) involve planting a small field of sunflower or other crop to attract the birds away from the commercial sunflower field. The goal is to keep the birds in the lure crop as long as possible to reduce the time spent in nearby commercial sunflower fields. Farmers can continue to spray registered repellents and harass birds in their commercial fields to encourage the birds to feed in the lure crops.
from USDA APHIS, National Wildlife Research Center, Feb. 2011



Bear Damage

The following important information provided by the NJ Division of Fish & Wildlife discusses deterrence practices for Black Bear depredation.  

Black bears like a wide variety of foods including sweet corn, field corn and insects. Livestock including chickens, rabbits, sheep and goats are also subject to depredation by black bears. The following information is offered to help farmers deter black bears if they are experiencing crop, orchard, garden, or beehive damage or livestock depredation.


Farming Practices for Crop Protection Against Bear Depredation

The DEP Division of Fish and Wildlife recommends the following farming practices for protecting corn and grain crops, orchards, vegetable gardens and compost piles, apiaries and livestock from depredation by black bears:

  • Livestock pens, beehives, vegetable gardens and compost piles should be located at least 50 yards from forest tree lines, wetlands, or other cover for bears.
  • Crops, such as sweet corn, field corn or grain, should be planted as far away as possible from forest tree lines, wetlands, or other cover for bears.
  • Keep areas around livestock, crops, beehives, orchards, gardens and compost piles well mowed to reduce cover for bears.
  • Black bears may be repelled by installing mechanical scare devices around livestock, pastures, crops, beehives, orchards, gardens or compost piles, which activate by a motion-sensing device. Scare devices include noise-making pyrotechnics, electronic sirens, strobe lights and noise generators.
  • Electric fencing is the most effective and efficient method of preventing bear damage to livestock, beehives, crops, silage bags, orchards, gardens and compost piles. Fencing is only effective if it is properly installed and maintained.
Extensive Additional Tips

Protecting Livestock

  • Livestock feed should not be left out overnight unless enclosed in a certified bear-resistant container ( ). Store feed in a secure area.
  • Carcasses of dead animals should be properly disposed of or destroyed to prevent black bears from scavenging near susceptible livestock or crops.

Protecting Orchards

  • Farmers with fruit trees should recognize that bears will be attracted to any fruit left on the ground. To minimize bear activity, pick up any fruit that falls from trees daily. Discard fruit in certified bear-resistant garbage containers ( ).
  • Individual trees may be protected by using proper fencing techniques, such as electric fencing, if the limbs, leaves, and fruit are at least eight feet off the ground.

Protecting Gardens/Compost Piles

  • Harvest gardens immediately as vegetables mature. Keep gardens free of vegetable wastes.
  • Do not place meat, dairy or sweet foods in compost or mulch piles. Adding lime can reduce odors and help decomposition.

Nuisance Control Measures

Depredation permits are available to eligible farmers who are experiencing crop and livestock depredation by black bears. For more information, contact the Division of Fish and Wildlife at: 

1-877-WARN DEP (1-877-927-6337).

Electric Fencing Construction

Properly installed electric fencing is the most effective and efficient method of preventing bear damage to livestock, beehives, crops, silage bags, orchards, gardens and compost piles.

The Division's Wildlife Control Unit is available to provide on-site assistance with fence construction to those interested in installing electric fencing to prevent bear damage to beehives, agriculture crops and livestock. For more information, contact the Division of Fish and Wildlife at:

1-877-WARN DEP (1-877-927-6337).


Fence construction should be simple and as strong as possible. The following method of fencing is easy to erect and effective in most cases.

  • Drive the corner posts. Use wooden posts and reinforce them with braces. Remove grass and weeds in an 18 inch strip along the fence line.
  • Spray the cleared area with a herbicide to prevent the return of vegetation. Do not spray wider than 18 inches because the bear will be better grounded if it is standing on grass.
  • Use five strands of high tensil wire, barbed wire or electronet at 4 inches, 16 inches, 26 inches and 36 inches above the ground. Stretch the wires to eliminate sagging. Use stones or weights to keep the wires at the correct heights when going over low areas.
  • Leave extra wire at the knot so it can be wrapped around the lower wire to complete the circuit.
  • Use a minimum voltage output of 3,000 volts. Verify this with a voltmeter. Energizers should be compatible with the type of wire used. Check the manufacturer's recommendations to be sure that all the requirements are met.
  • Locate the fence posts 12 feet to 15 feet along the fence line. Install the insulators and wire.
  • Energize all wires in the fence system. The battery should be located inside the enclosure. When possible, use direct current for the initial two months, then switch to battery or solar power.
  • Drive the ground rod 5 feet to 7 feet into moist soil.

Baiting the Fence

  • Bait the wires on the electric fence to direct a mild shock onto the muzzle area of a black bear. This makes the fence much more effective, regardless of the size of the bear.
  • Bait the wires with either bacon wrapped around the wire on all sides or tin foil and peanut butter. When a bear grabs the bait, it will get a shock to its tongue and mouth.


The following tips are offered to ensure proper maintenance and effectiveness of your electric fence. Every time you visit the site check the following:

  • Make sure the wires are tight.
  • Change the batteries as needed.
  • Drop loops in wires are beneficial.
  • Use at least a 70-amp hour battery.
  • Consult your supplier for the correct high output fence charger.
  • Check voltage with a voltmeter.
  • Marine battery terminals and lead composition eyelets resist corrosion.
  • Keep wires baited at all times.
  • Remove vegetation that may be touching the wires.


Additional Resources

Electric Fencing Resources

Living with Wildlife Foundation's Electric Fencing Guide

Electric Fencing Supplies

Kencove Farm Fence, Inc