Ask a Specialist: Groundhogs, Woodchucks and Marmots
Tuesday, Jul. 15, 2014
July 15, 2014
Ask a Specialist: Groundhogs, Woodchucks and Marmots: a Different Kind of Squirrel, but Still a Squirrel
By: Terry Messmer, USU Extension wildlife specialist, firstname.lastname@example.org
In recent weeks, reports of woodchucks have increased as they have been sighted foraging in alfalfa fields, raiding gardens, harassing dogs, crossing highways and digging borrows under barns, homes and cabins. These “whistle pigs” have been sighted in areas where they have never been before, including main street.
Woodchucks, ground hogs, marmots and whistle pigs are one in the same. And although they would have difficulty scurrying among tree branches, they are all members of the squirrel family and are able to climb. Woodchucks are a protected species in Utah; however, they may be taken without a permit.
Short, strong legs support their compact, chunky body. Their forefeet are equipped with curved claws that are well adapted for digging burrows. Both sexes have short, dark brown fur and they may weigh more than 10 pounds. Woodchucks have white or yellow/white, chisel-like incisor teeth that are regularly growing. To keep the incisors in check, they have to constantly gnaw. Their eyes, ears and nose are located toward the top of the head. This unique feature allows them to remain concealed in their burrows while they check for danger.
Woodchucks in Utah generally prefer open areas that are near some type of cover. Burrows are commonly located in fields and pastures, along fence rows, stone walls, roadsides and near building foundations or at the base of trees. A large mound of excavated earth at the main entrance readily identifies their burrows. For protection, the burrow usually has two or more entrances. The secondary exits are usually hidden by vegetation. Woodchucks generally stay within a few hundred feet of their burrow in the daytime. This distance may vary during mating season or depending on the availability of green groceries.
Woodchucks usually feed in the early morning and evening. As an herbivore, almost anything green can be table fare. However, they prefer vegetables, grasses and legumes such as alfalfa, peas and beans. Woodchucks are among the few mammals that enter into true hibernation. Hibernation generally starts near the end of October or early November.
Between hibernations, woodchucks’ burrowing activity and diet can get them in trouble with humans. Damage often occurs on farms, in home gardens, orchards, nurseries, around buildings and sometimes around dikes. Damage to crops such as alfalfa can be costly and extensive. Fruit trees and ornamental shrubs are damaged by woodchucks as they gnaw or claw woody vegetation. Gnawing on underground power cables has caused electrical outages. Mounds of earth from the excavated burrow systems and holes formed at burrow entrances present a hazard to farm equipment, horses and riders.
Consider this information to reduce woodchuck damage.
* Fencing can help reduce damage. Because woodchucks are good climbers, fences should be at least 3 feet high and made of heavy poultry wire. To prevent burrowing under the fence, bury the lower edge 10 to 12 inches in the ground or bend the lower edge at an L-shaped angle leading outward, then bury it in the ground 1 to 2 inches. As an extra deterrent, place an electric wire 4 to 5 inches off the ground and the same distance outside the fence. The electric wire will prevent climbing and burrowing. Fencing can protect home gardens and offer added protection by excluding rabbits, dogs, cats and other animals.
* A gas cartridge (carbon monoxide) can be used to euthanize problem woodchucks in their burrows. These are commercially available. Directions for their use are on the label and should be carefully read and followed. When using gas cartridges, do not use them in burrows located under wooden sheds, buildings or near other combustible materials because of the potential fire hazard. In addition to gas cartridges, aluminum phosphide tablets are registered for this use. Aluminum phosphide is a restricted-use pesticide and can be applied only by a certified pesticide applicator. For guidelines regarding the use of this fumigant, contact you local USU Extension county office.
* Woodchucks can also be live trapped. These traps are often available through local farm and ranch stores. The traps should be baited with apple slices or vegetables such as carrots and lettuce, and baits should be changed daily. Leave traps at main entrances or major travel lanes. Place guide logs on either side of the path between the burrow opening and the trap to help funnel the animal into the trap. Check all traps in the morning and evening so that captured animals may be quickly removed. A captured animal can be relocated to an area with suitable habitat where no additional damage can be caused. For more information on managing damage caused by woodchucks, contact your local USU Extension office.