A pack rat (white-throated woodrat, Neotoma albigula) is a medium-sized native rodent found throughout Arizona. They are known for building large stick nests called middens and collecting shiny objects. They are 6 to 8 inches long with large ears, large dark eyes, and a white belly. They are primarily nocturnal.

How do I know if I have pack rats?

Signs include large stick piles (middens) near structures, under vehicles, or in dense vegetation; gnaw marks on wiring, hoses, or irrigation lines; droppings about the size of a raisin; strong musky odor; and damage to vehicle wiring.

Will pack rats damage my car?

Yes — pack rat vehicle damage is extremely common in Arizona. They nest in engine compartments and chew through wiring harnesses, hoses, and insulation. Damage can range from a few hundred to several thousand dollars. Parking in a garage and placing wire mesh under the vehicle are the most effective preventive measures.

How do I get rid of pack rats?

Snap traps or live traps baited with peanut butter, apple, or nesting material are the most effective method. Place traps along runways and near middens. After trapping, remove the midden wearing gloves and a respirator, and treat the area with disinfectant. Seal entry points and remove vegetation near structures to prevent reinfestation.

Are pack rats the same as roof rats?

No. Pack rats (woodrats) are native desert rodents that build large stick nests outdoors. Roof rats are an invasive species that primarily invade structures, nest in attics and walls, and are more closely associated with food contamination.

What attracts pack rats to my property?

Pack rats are attracted to dense vegetation (especially cactus), wood piles, debris, and any sheltered cavity. They are also attracted to vehicles, which provide warmth and shelter. Removing cactus and dense vegetation within 3 feet of structures significantly reduces pack rat activity.

How much does pack rat removal cost in Arizona?

Professional pack rat trapping and midden removal in Arizona typically costs $150 to $400 for a single infestation. Ongoing prevention programs run $75 to $150 per month. Vehicle wiring repair from pack rat damage can cost $500 to $3,000 or more.

Rodents

Pack Rats in Arizona: Identification, Damage & Removal

Q: Do pack rats carry hantavirus?

Yes. Pack rats (woodrats) can carry hantavirus, a serious respiratory illness transmitted through contact with infected rodent droppings, urine, or nesting material. Always wear gloves and an N95 respirator when handling pack rat nests or cleaning areas with rodent activity.

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Hantavirus Risk

Always wear gloves and an N95 respirator when handling pack rat nests or cleaning areas with rodent activity. Wet down the area with disinfectant before disturbing it to reduce airborne particles.

Pack rats — also called woodrats — are one of the most destructive rodents in Arizona. They build massive stick nests, chew through vehicle wiring, and contaminate properties with hantavirus-risk droppings. Learn how to identify pack rat activity, assess the damage, and get rid of them for good.

The white-throated woodrat (Neotoma albigula), commonly called the pack rat, is one of the most problematic rodents in Arizona. Unlike roof rats and house mice that primarily invade structures, pack rats are notorious for building large, elaborate stick nests — called middens — in and around homes, under vehicles, in engine compartments, and in dense vegetation. These nests can grow to the size of a washing machine and contain cactus spines, sticks, debris, and anything shiny or interesting the pack rat has collected. Pack rats are medium-sized rodents, 6 to 8 inches long with a 5 to 7 inch tail, with large ears, large dark eyes, and a white or cream-colored belly. They are primarily nocturnal and are most active from dusk to dawn. In Arizona, pack rats are found throughout the state but are most common in desert areas with saguaro cactus, prickly pear, and cholla.

Pack Rat Damage in Arizona

CRITICAL

Vehicle Wiring

Chew through wiring harnesses, hoses, and insulation — $500–$3,000+ in damage

HIGH

Irrigation Lines

Chew through drip lines and PVC irrigation — causes flooding and plant death

HIGH

Electrical Wiring

Structural wiring damage creates fire hazard

MEDIUM

HVAC Components

Nest in ductwork and chew through insulation

HIGH

Secondary Pest Attraction

Middens attract scorpions, black widows, and rattlesnakes

Pack rat damage in Arizona falls into several categories. Vehicle damage is among the most costly — pack rats are notorious for nesting in engine compartments and chewing through wiring harnesses, hoses, and insulation. A single pack rat can cause thousands of dollars in vehicle damage in a matter of days. They also chew through irrigation lines, electrical wiring in structures, and HVAC components. Their urine and droppings contaminate surfaces and can harbor hantavirus — a serious respiratory illness transmitted through contact with infected rodent droppings, urine, or nesting material. Pack rat middens also attract other pests, including scorpions, black widows, and rattlesnakes that use the nest for shelter. Signs of pack rat activity include large stick piles near structures or under vehicles, gnaw marks on wiring or hoses, droppings larger than mouse droppings, and the strong musky odor of pack rat urine.

How to Get Rid of Pack Rats

Effective pack rat control requires a multi-step approach. Trapping is the most reliable method — snap traps and live traps baited with peanut butter, apple, or nesting material placed along pack rat runways and near middens. After trapping, the midden must be removed and the area treated with a disinfectant — always wear gloves and a respirator when handling pack rat nests due to hantavirus risk. Prevention includes removing cactus and dense vegetation within 3 feet of structures, parking vehicles in garages when possible, placing wire mesh under vehicles, and sealing all entry points into structures. Professional pest control is strongly recommended for pack rat infestations due to the hantavirus risk and the complexity of midden removal.