WOOD RATS

Identification
Eight species of woodrats (genus Neotoma ) occur in North America . Locally known as pack rats or trade rats, these rodents are about the size of the common Norway rat. They are distinguishable from Norway rats by their hairy rather than scaly tail, soft, fine fur, and large ears. They usually have light-colored feet and bellies.

Range
Each species of woodrat is generally restricted to a given type of habitat within its range. Woodrats occur from low, hot, dry deserts to cold, rocky slopes above timberline.

Habitat
Scrub jays commonly inhabit the oak and brush-covered foothills of the mountains, timbered canyons, river bottoms, oak-lined sloughs and creeks, as well as the shade trees and dense shrubbery of residential areas.

Food Habits
The food habits of woodrats are relatively specific for the individual species. Species such as the bushytail woodrat , for example, feed primarily on green vegetation, twigs, and shoots, whereas the Mexican woodrat feeds on seeds, fruits, acorns, and cactus. Woodrats may also be attracted to human food supplies in buildings. When nesting inside buildings, woodrats usually continue to feed outside. Trails 3 to 4 inches (8 to 10 cm) wide from the building to the outside may be visible.

General Biology, Reproduction, and Behavior
Woodrats climb readily and are usually active at night. Most species build a large stick den or house on the ground or in trees, but some species live in rocky outcroppings. These houses are typically occupied by one individual or by a female and her young. One animal may inhabit several houses. A nest, usually made of finely shredded plant material, is located within the larger house. Breeding usually occurs in the spring. Woodrats produce 1 to 4 young per litter and may produce more than 1 litter per year in the southern parts of the United States.

Damage and Damage Identification
Populations generally are fairly dispersed, but economic damage to agricultural crops can occur in limited areas. Agricultural damage results when woodrats clip small twigs and branches, and when they debark citrus and other fruit trees and seedling and sapling conifers, especially redwoods. Loss of trees can occur.

Woodrats are sometimes a nuisance around cabins, outbuildings, and other infrequently used structures or vehicles. As the name "packrat" implies, they have a tendency to pack away small objects such as jewelry, cooking and eating utensils, can tabs, and other items. At times, this behavior can become a nuisance to backpackers and others. More seriously, woodrats may also shred upholstered furniture and mattresses for lining nests, and may take up residence in parked vehicles, gnawing on wires and other mechanical components.

Woodrats can be an important factor in the transmission of certain diseases, most notably plague, where this disease occurs. Dead or dying woodrats should not be handled.

Economics of Damage and Control
Nationally, woodrats are a minor pest. They only occasionally become numerous enough to cause significant agricultural damage. In most cases, woodrats are a nuisance around vacation homes, cabins, and other outbuildings. Their stick nests can be extensive and their physical presence and droppings are often objectionable. Woodrats can carry diseases and ectoparasites . Therefore, close association with humans is undesirable. In most nuisance situations, control can be accomplished by the resident or homeowner.

Legal Status
Woodrats are classified as non-game animals. In most states they can be taken (controlled) when they threaten or damage property. Check with your local wildlife or agriculture department for laws and regulations specific to your area. For example, the Key Largo woodrat ( Neotoma floridana smalli ) was federally listed as endangered in 1991.

Damage Prevention and Control Methods

Exclusion
Woodrats can be permanently excluded from buildings.

Habitat Modification
Glue Boards.

Toxicants
Anticoagulants (registered in some states). Zinc phosphide (registered in some states).

Fumigants
Not useful.

Trapping
Rat snap trap. Live Traps.

Shooting
Limited usefulness.

Other Methods
Destruction of dens. Not generally useful. Trim lower branches of citrus trees.

ACKNOWLEDGEMENTS
The above information was adapted from PREVENTION AND CONTROL OF WILDLIFE DAMAGE with permission of the editors, Scott E. Hygnstrom, Robert M. Timm, and Gary E. Larson (Cooperative Extension Division, Institute of Agriculture and Natural Resources University of Nebraska-Lincoln, United States Department of Agriculture Animal and Plant Health Inspection Service, Animal Damage Control, Great Plains Agricultural Council Wildlife Committee).