Woodchucks

The woodchuck (Marmota monax), also known as the groundhog, whistle pig, or marmot, is one of the most widely distributed animals in the Northeast. It is the largest member of the squirrel family. Many people regard the woodchuck as a nuisance, however they are beneficial in that their burrows help aerate the soil and also provide denning sites and refuge for many other animals such as rabbits and foxes.

The woodchuck has a compact, hefty body, short, strong legs with long, curved claws on the forefeet for digging, and a short tail. It is heavily furred and dark brown in color, weighs from 5 to 10 pounds, and is (16 to 20 inches long. Although they are slow runners, woodchucks are alert and can quickly move into their dens when alarmed.

Habits and Damage

Woodchucks hibernate during the winter, becoming active in late February and March. Mating occurs in March. By late June or early July the young strike out on their own--usually occupying old, abandoned dens. The numerous new burrows that appear during the late summer are dug by older woodchucks.

Woodchucks are active during the day and their range is approximately 50 to 100  feet from their dens. The den and burrows are extensive and may be used for several years. Burrows may be as deep as 5 feet and up to 60 feet long. Woodchucks seem to prefer to construct burrows on or near farm land where crops grow. They frequently may be found in woodlands or in abandoned farm lands and occasionally in urban areas where the combination of food and cover provides a satisfactory habitat.

Woodchucks are voracious feeders, feeding actively on succulent, green vegetation in early morning and evening periods during summer as they store body fat in preparation for hibernation, usually near the end of October or early November. Damage to crops and gardens can be extensive. A woodchuck or two can literally destroy an entire garden. Woodchucks feed primarily on vegetables, trees, grasses, and legumes. Rows of newly sprouted peas or beans, neatly clipped with only an inch of stem remaining is often a sign that there are woodchucks in your garden. Their gnawing and clawing can kill young fruit trees. They gnaw on the main stems of trees and lower branches close to the burrows and the damage easily distinguished from vole gnawing by the large size of the incisor teeth marks 1/4 to 3/8 inch wide.

Control

Fencing of small gardens may prove an effective means of preventing damage. The fencing must be rigid, no less than three feet high and buried to a depth of no less than 10 to 12 inches. The size of some gardens or agricultural plots may make this option impractical. Also due to their ability to climb, fencing may not be effective in all cases. Electrifying the fence will make it much more effective. Fencing placed around the bottom of sheds will prevent woodchucks and other animals’ access.

The use of ammonia-soaked rags in or at the entrance to woodchuck burrows may be irritating enough to encourage the animal to abandon the burrow. The rags must be changed regularly to be most effective.

Planting certain types of flowers, such as marigolds which apparently are distasteful, around or within the garden may discourage woodchucks. There are few garden crops that woodchucks will completely avoid; some such as peas, beans, broccoli, and carrots are more sought after than others. Try to avoid planting those crops that experience has shown are attractive to woodchucks. Young plants are more susceptible to woodchuck damage than older plants.

Woodchucks can be easily trapped in cage or box-type traps using apples as bait. Traps should be set as close as possible to burrows or travel ways and should be checked at least twice a day. Be especially careful on hot summer days as the animal will quickly overheat in the trap. The woodchuck is considered a “target” animal for rabies (i.e., having a high risk for contracting the disease), therefore, state regulations prohibit the relocation of captured animals. Captured animals may only be released at the site of capture or euthanized in a humane manner.  Drowning is an option, but woodchucks can apparently live for at least 15 minutes underwater. The use of foothold traps, snares, and poisons are prohibited in Rhode Island.

Commercial gas cartridges filled with slow-burning chemicals are available at garden supply stores. These are ignited and placed in the burrows and the entrances are sealed. Woodchuck burrows are distinguished by a large  mound of excavated earth at the main entrance; there are always two or more entrances to each burrow system. As the cartridges burn, carbon monoxide and sulfur dioxide fill the tunnels and kill the woodchuck. Before using these cartridges, read and follow all instructions and cautions on the label; gas cartridges can pose a fire and health risk.

No poisons or poisonous baits are registered for woodchuck control in Rhode Island.

In many instances, the offending animal is dispatched by the property owner with the use of a firearm. This may not be safe or legal in all situations. For specific laws and regulations regarding the use of firearms consult the Department of Environmental Management.

Adapted from: Norman L. Gauthier, University of Connecticut Integrated Pest Management Program, 1999; Rhode Island Department of Environmental Management

Useful Website

RI Department of Environmental Management

http:// www.dem.ri.gov