Signs of Pack Rats in Your Garage or Vehicle — A Pecos Valley Problem

Meet the pack rat

The white-throated woodrat is a native desert rodent, not an escaped pet. Stocky, grey-brown, with big ears and a bushy tail, it's nocturnal and built for the high desert. In the wild it builds sprawling "middens" of sticks, cholla joints, bones, and whatever shiny junk it drags home — they're famous collectors. Around Roswell, especially on edge-of-town lots backing onto desert or farmland, those middens move into garages, sheds, crawlspaces, and vehicle engine bays. A pack rat isn't passing through like a wandering mouse; once it sets up housekeeping, it's a resident.

Signs in the garage

Look for oval droppings (larger than mouse pellets) along walls and workbenches, and the nests: bulky bundles of twigs, insulation, shredded cardboard, sometimes cactus pieces, tucked behind stored boxes or in rafters. Chew marks appear on plastic bins, stored decorations, wiring on garage appliances, and the weatherstripping at the door itself. There's often a sour, musky urine smell in the corner where they're denning, plus small caches — piles of seeds, dog food, or prickly pear pads — along the route. Greasy rub marks along baseboards and shelf edges mean steady traffic, not a one-time visitor.

Signs in the vehicle

This is where pack rats get expensive. They nest under the hood where it's warm and sheltered, and they chew wiring insulation — modern soy-based wire coatings make it worse. Warning signs: check-engine or sensor lights that appear out of nowhere, rough running, or a vehicle that simply won't start after sitting for a few days. Pop the hood in the morning and look for nests of insulation and droppings on the battery tray, chewed hoses, and seeds or shells on the engine cover. Rodent-caused wiring damage runs into the hundreds or thousands per incident — a truck parked near a desert lot is a target, not an accident.

Where they get in

Pack rats squeeze through gaps as small as half an inch: garage doors that don't seat fully, missing or worn door sweeps, gaps around utility lines, uncapped wall vents, and doors left open after dusk. Inside, clutter is shelter — stored boxes, stacked firewood against the garage wall, spare tires, and pet food or birdseed in easy bags are invitations. Properties edging the Pecos Valley desert, arroyos, or farmland get pressure all year, but late fall and cold snaps push them toward garages and engine bays hardest.

Removal and exclusion that works

Start by removing the welcome mat: seal gaps half an inch and up with hardware cloth, steel wool and caulk, or metal flashing (foam alone gets chewed straight through). Tighten the garage door, fit sweeps, and screen vents. Move firewood and stacked materials off the ground and away from walls; store birdseed, pet food, and decorations in hard plastic bins. Trap remaining animals with snap traps along their runways — bait with peanut butter, dry pet food, or nesting material — and keep trapping until activity stops. Skip the mothballs, dryer sheets, and ultrasonic plug-ins: there's no good evidence they move a settled pack rat. For heavy infestations or vehicle damage, a licensed pro's exclusion-and-trapping program ends it in weeks rather than the months DIY usually takes.

Keeping them out for good

Pack rat control is maintenance, not a one-time event. Keep the garage door closed after dark and tidy enough to spot new droppings. If a vehicle sits more than a few days, park it clean and hood-latched — some owners pop the hood open overnight so the engine bay stops feeling like a den. Pull xeriscape mulch and prickly pear back from the garage wall; those are pack rat furniture. And run the surveillance: a quick flashlight check behind stored boxes once a month catches the next den before it becomes a wiring bill.