Oveview of Damage Prevention and Control Methods
- Encourage closed-canopy forest stands
- Fences (small areas)
- Tree trunk guards
- None are registered
- Some wood preservatives may incidentally repel porcupines
- None are registered
- Day shooting and spotlighting are effective where legal
- Steel leghold trap (No. 2 or 3).
- Body-gripping (Conibear®) trap (No. 220 or 330).
- Box trap
- Encourage natural predators
Damage Prevention and Control Methods
Porcupines are mobile and continually reinvade control areas. Complete control is not desirable since it would require complete removal of porcupines. Try to limit lethal porcupine control to individual animals causing damage by fencing and management of the plant species. In areas of high porcupine populations, plant ornamentals that are not preferred foods. Intensive predator control may encourage porcupine population increases.
Thinned forest stands are vulnerable to porcupine damage because lower vegetation can thrive. Porcupine populations are usually lower in closed canopy stands where understory vegetation is scant.
Fencing small tree plantings, orchards, and gardens is effective in reducing porcupine damage. Electric fences are effective when the smooth electric wire is placed 1 1/2 inches (3.8 cm) above 18-inch-high (46-cm) poultry wire. A 4- to 6-inch (10- to 15-cm) electric fence can be enhanced by painting molasses on the wire. Porcupines will climb fences, but an overhanging wire strip around the top of the fence at a 65o angle to the upright wire will discourage them.
Completely enclose small trees with wire baskets or encircle the trunks of fruit and ornamental trees with 30-inch (70-cm) bands of aluminum flashing to reduce damage.
Common wood preservatives may repel porcupines when applied to exterior plywoods. Avoid using wood preservatives that are metal-salt solutions. These will attract porcupines.
No toxicants can be legally used to control porcupines.
Persistent hunting and shooting of porcupines can be effective in reducing the population in areas that require protection. Night hunting, where legal, is effective. During winter months, porcupines are active and can be tracked in the snow and shot with a .22-caliber rifle or pistol. Porcupines often congregate around good denning sites and extensively girdle trees in the area. In such places large numbers may be taken by shooting.
Steel Leghold Traps
Steel leghold traps of size No. 2 or 3 can be used to catch porcupines where legal. Cubby sets with salt baits, trail sets in front of dens, and coyote urine scent post sets near dens and damage activity are effective. Scent post and trail sets must be checked daily to release nontarget animals that might be caught. Leghold traps should be bedded, firmly placed and leveled, and offset slightly to the side of the trail. The trapped porcupine can be shot or killed by a sharp blow to the head.
The No. 220 or 330 Conibear® body-gripping trap can be baited with a salt-soaked material or placed in den entrances to catch and kill porcupines. Care must be taken to avoid taking nontarget animals, since salt attracts many animals. The Conibear® trap does not allow the release of accidental catches. Some states do not allow the use of No. 330 Conibear® traps for ground sets.
Porcupines are rather easy to livetrap with large commercial cage traps (32 x 10 x 12 inches [81 x 25 x 30.5 cm]) or homemade box traps. Place the live trap in the vicinity of damage and bait with a salt-soaked cloth, sponge, or piece of wood. Live traps also can be set at den entrances. If legal, move the porcupine 25 miles (40 km) or more to ensure that it does not return. Since most areas of suitable habitat carry large porcupine populations, relocation of the porcupine often is neither helpful nor humane since the introduced animal may have a poor chance of survival.
Other Control Methods
Predators of porcupines include coyotes, bobcats, mountain lions, black bears, fishers, martens, great horned owls, and others. Coyote scats (feces) containing large numbers of quills are not unusual. How the quills are maneuvered through the coyote’s gastrointestinal tract is a mystery. Encourage predators if possible.