Rodent Exclusion and Control

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About rats and mice
Signs of rodent activity
Prevent rodent problems
Control rodents
Clean up safely
Educational inspection

About rats and mice

Rodents found in homes, such as rats and house mice, can spread disease, contaminate food, and cause costly damage to structures. Wild mice can spread a disease called hantavirus. Learning to recognize signs of rodent activity and how to prevent and control rodent problems can protect you and your home.

The Vector Control Program provides educational rodent inspections FREE to county residents and includes a Rat Control Starter Kit with instructions on how to properly control rats.

The Vector Control Program is not a pest control company and does not trap, bait, or remove rodents, including gophers or squirrels, as part of the inspection or provide poison bait. More information about different pests can be found on the UCIPM pest resource page.

Signs of rodent activity

Droppings in garages, storage buildings or other sheltered areas
Gnaw marks on food, food containers, or insulation inside walls and electrical wires
Nests built from fine shredded paper and other fibrous materials or shredded areas
Rub marks caused by greasy rat fur
Bark stripped from plants and trees
Piles of empty snail shells hidden under plants or piles of wood
Sounds in the attic, floor, and walls

Prevent rodent problems

Prevent rodent problems by getting rid of things that attract rats and mice like food, water, or shelter that they can get into.

Check your home and storage buildings

Check the outside of your house for holes or gaps
Rats can enter through holes the size of a quarter or larger
Mice can enter through holes the size of a dime or larger
Repair all holes using rodent proof materials: 1/4-inch, 18-22 gauge wire hardware cloth
You can also seal holes with a combination of metal wool and expanding foam
Put metal weather stripping under doors to remove gaps
Trim trees and bushes to at least 4ft away from the roof to prevent rats from jumping onto your roof

For more information visit the CDC website How to Seal Up to Prevent Rodents

Additionally see our video on Keeping Your Restaurant Vermin-Free

Remove food sources from your property

Always keep garbage cans covered
Pick fruit, nuts, and vegetables as they ripen
Throw away or compost fallen fruit on the ground
Feed pets during daylight hours only, and remove uneaten food right away
Avoid storing food in garages and storage sheds at night unless in rat-proof covered metal containers
Avoid feeding birds, or clean up any fallen bird seed around feeders

Get rid of rat habitat

Remove all trash and debris
Stack woodpiles, lumber, and household items at least 18 inches above the ground and 12 inches away from fences and walls
Trim trees, bushes, and vines to at least 4 feet away from the roof
Remove heavy vegetation such as ivy, bougainvillea, and pyracantha from buildings and fences
Thin vegetation to allow daylight in and remove rat hiding places

Control rodents

Use snap traps to control rodents

Place traps along walls, behind objects, in dark croners, or where you have seen rats or rat droppings
Use CAUTION when placing traps around children or pets
Bait the traps with peanut butter or the food the rats have been eating
Tie down traps to prevent injured rats from dragging the traps away and dying inside your walls
Bait with food for a few dats before setting the trigger. Rats learn traps are "safe" and become easier to catch
Check traps daily - double bag dead rats and put them in the trash

For more information visit the CDC website How to Trap Up to Remove Rodents

Use poison bait OUTDOORS if necessary

Never use baits indoors or under the house. Poisoned rats may die inside walls or attics, creating odors and attracting flies
Rodent proof your home BEFORE using poison bait. Baiting is illegal without a tamper-proof bait station. Tamper-proof bait stations prevent children, pets and nontarget animals from getting into the bait. They also protect the poison bait from sun and rain.
Place the bait station where you see rat activity and in a protected area such as under woodplies or thick vegetation where rats may be hiding
Always read and follow all label instructions and precautions
Check bait stations twice a week and add bait when the supply is low
When the job is finished, uneaten rodenticides should be removed and disposed of according to the label
Double bag dead rats and pit them in the trash

A note on using rodenticides: Anticoagulant rodenticides can be harmful to nontarget wildlife. If poisoned rodents are consumed as prey or scavenged, this can lead to the death of wildlife and pets. This is known as secondary poisoning. Rodenticides must be used cautiously and in consideration of non-target wildlife and pets. They should be used ONLY OUTDOORS in a tamper-proof bait station.

Clean up safely

Lower your exposure to airborne particles when cleaning up rodent droppings:

Air out unused rooms or buildings that have been empty for a long period of time. Leave doors and windows open for 30 minutes.
Wear latex or rubber gloves and protective respiratory equipment, such as a face mask
DO NOT sweep or vacuum up rodent droppings, urine, or nesting materials. This can stir up the virus particles.
Instead, use the WET CLEANING METHOD:
1. Make a disinfectant solution (9 parts water to 1 part bleach) or use a commercial disinfectant making sure to follow the label instructions
2. Spray the disinfectant solution on polluted areas, including dead rodents or droppings, and let sit for 15-20 minutes before cleaning
3. Soak sponges in the disinfectant solution and clean
4. Place dead rodents, nesting material, and all cleaning supplies in a sealed plastic bag. Put this bag in a second bag and throw away
5. After cleaning, wash your gloved hands, remove the gloves and dispose of them, and then wash your bare hands as well with soap and water

For more information visit the CDC website How to Clean up After Rodents

Educational Inspections

The Vector Control Program provides educational rodent inspections FREE to San Diego County residents. Inspections are performed on the outside of the buildings. This inspection includes a free Rat Control Starter Kit. The kit will help you to control rats yourself and provides examples of materials needed. It includes:

Tamper-resistant trapping station including snap trap and key
Rat control brochure
Sample of 1/4" hardware cloth (used for sealing entry points)

The Vector Control program is NOT a pest control company. We do NOT trap, bait, or remove rodents as part of this inspection, and do not provide poison bait.

To request a rat inspection contact the Vector Control Program.