How to tell you have pack rats
Look for piles of sticks, cactus and debris in sheds, crawlspaces, attics or engine bays. Other signs are chewed wiring or hoses, and droppings that are larger than mouse droppings. Pack rats are mostly active at night.
Why they matter
Pack rats chew vehicle wiring and stored items, and their nests hold droppings and urine. The NM Department of Health lists woodrats among the wild rodents whose fleas can carry plague in New Mexico. Avoid handling nests or dead rodents with bare hands, and follow public-health cleanup guidance.
Prevention
Clear brush and debris piles away from buildings, store firewood off the ground and away from the house, and seal sheds, garages and crawlspaces. A vehicle that sits for weeks is especially attractive to them.
Frequently asked questions
Are pack rats the same as house mice?
No. Woodrats are larger native rodents that build stick nests. House mice are smaller, and they usually nest in insulation, walls and cabinets.
Should I sweep out a pack rat nest myself?
Public-health agencies advise against sweeping or vacuuming rodent nests and droppings because that can put contaminated dust into the air. See the CDC rodent cleanup guidance, or have a professional handle large nests.
Can pack rats damage my car?
Yes. They often nest in engine compartments and chew wiring. Sealing garages and removing nearby nests reduces the risk.
Sources
- NM Dept. of Health: Plague
- CDC: How to Clean Up After Rodents
- CDC: Controlling Wild Rodent Infestations
This page is general information, not medical, legal or regulatory advice. For health concerns, contact a healthcare provider or the NM Department of Health. For wildlife regulations, contact NM Game & Fish (NMDOW). Last reviewed Oct 2026.
