Control of Rats and Mice

Rats and mice can be found in homes, farm and ranch buildings, sheds and garages. They are offensive in many ways:

• They eat and contaminate all types of food.
• They damage and destroy property.
• They carry diseases that are health hazards to both humans and animals-diseases such as typhus fever, Trichinosis, plague,infectious jaundice, Salmonella food infections, and rat mitedermatitis.

Identification of Rats and Mice

The signs of a rat or mouse infestation include droppings,tracks in the moist earth or dusty places, and burrows in the ground. There will be signs of gnawing and runways in the grass or through trash.You also can smell the presence of rats and mice,especially in a poorly ventilated room.

Methods of Control

The principal means of controlling rats and mice are: Removal of shelter. Removal of water and food. Use of rodenticides and traps. Sealing possible entries to a building.

Removal of Shelter

Piles of lumber, trash or other materials can be shelters for rats. Trash, such as empty boxes and cartons, should be discarded of promptly. Stored materials should be at least 18 inches off the ground or floor, and with space between the material and the wall.

Removal of Water and Food

The best way to eliminate the food supply of rats and mice is to store food in glass or metal containers, and to put garbage in tightly covered trash cans. Repair leaky faucets and remove any water that rodents have access to.

Use of Rodenticides and Traps

Rodenticides. One effective way of destroying rats and mice, and the one most generally recommended, is the use of rodenticides. There are many different kinds of rodenticides available. Most are anticoagulants, which cause death by internal bleeding because they prevent blood clotting. Anticoagulant baits are available in multiple-dose and single-dose formulations.Rats and mice must eat the multiple-dose bait every day for 5 to 6 days, or every other day for at least 12 days before hemorrhages are fatal. Single-dose anticoagulant bait needs to be eaten by rats and mice only once before they die. Since the rodents feel no pain, there is no warning and they continue to feed if the bait is attractive.

Exposing the bait

For Rat Control. Offer dry anticoagulant bait to rats in 1 /4 to 1 /2 pound packages. Place bait less than 25 feet apart where rats feed along walls,i side and outside buildings, in dark corners,under floors, in attics and under stairways. To hurry feeding, cut paper sacks so that bait spills out. Keep replenishing the bait until the rats stop eating. When anticoagulant baits become old, replace them with fresh bait.

In addition to the dry form, a water-soluble bait is available for use in water. This is particularly effective in dry surroundings and where there is already another food available.

For Mice Control. Mice also are effectively controlled with anticoagulant baits, but in smaller amounts. Place tablespoon amounts( 1 /4 to 1 /2 ounces) of bait at 8- to 12-foot intervals where mice travel, along walls, in corners and hidden places. Water-soluble bait is not needed in mouse control since mice require very little water.

Traps are just as effective but they require more effort. They work well where there are few rats and mice. The best place to set traps is close to walls in areas where rodents run. The selection of baits for tripping is important. Baits should be fresh and changed daily. Use a variety of baits on traps rather than a single kind of bait. Fruit, peanut butter and nuts all make good baits.

Sealing Possible Entries to a Building

All openings rodents can enter should be covered with rat-resistant materials such as hardware cloth or steel wool. Doors should be closed when not in use, and all edges subject to gnawing should be covered with metal. Unnecessary openings should be covered with concrete or sheet metal. Concrete also can be used to prevent rats from burrowing under foundations.

Measuring Results

Results cannot always be measured by counting dead rats and mice. When baits are no longer being eaten, when there are no fresh droppings and when no live rats or mice are seen, results are as good as can be expected.

Safety Precautions

Read the label carefully. Do not purchase anticoagulant bait that does not have full instructions on the label. Look for the Environmental Protection Agency (EPA)registration number. Anticoagulant bait can harm any animal or human eating it. Keep pets,livestock and people out of buildings where the bait is placed.

If a human consumes an anticoagulant bait,force the person to vomit by giving them a tablespoon of salt in a glass of warm water.Call a physician immediately. All anticoagulant labels or instruction leaflets give further instructions for doctors.

Destroy unused bait and containers by burning or burying deeply. Store any bait or poison out of reach of children and pets.

Texas Agricultural Extension Service · The Texas A&M University System Servicio de Extens ón Agrícola de Texas · El Sistema de Universidades de Texas A&M

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