Health Protection

What is it?

Rodent control refers to the elimination or reduction of rodents in and around buildings or land used by people for work, leisure or to live. Rodents, such as the Norway rat (also known as brown, common or sewer rat), roof rat and house mouse, commonly require control.

What is the problem?

Both rats and mice are considered pests because of the damage they do to food and property. Rats and mice can damage buildings and other articles by gnawing through rubber, aluminum and other soft metals (even light steel), cinder blocks, plastic, and wood. Rodents can contaminate food and other areas with their droppings, urine and fur. Mice need only an opening of 6 mm (0.24”) and rats only need an opening of 12 mm (0.47”) to get through. These rodents are also of concern because of the many serious diseases that are associated with them. They carry mites and fleas and spread diseases, such as Salmonella and Hantavirus. Mice and rats can be found almost everywhere. They are generally nocturnal animals and prefer narrow, concealed and out of the way routes when moving about. They tend to follow the same pathways but they are highly adaptable.

Rats

Rats normally live at or near ground level. They nest and burrow in the ground, under buildings, and in rubbish and other types of litter. They can climb, swim and jump very well. They have poor sight but excellent senses of hearing, smell, taste, and touch. Rats can roam up to 45 m (147.6 ft) from their nest. Their favourite foods include rolled oats, meat, fish, and vegetable oil.

Mice

Mice are well adapted for living year-round inside buildings. They are most likely to be noticed during winter following their fall migration indoors in search of warmth, food and shelter. Mice are excellent climbers. They have poor sight but excellent senses of hearing, smell, taste, and touch. Mice will only roam up to 9 m (29.5 ft) from their nest. Their favourite foods include grains, rolled oats, sugar, and raisins.

How do I know if I have a problem?

The easiest way to identify rodents is by seeing droppings. Mice droppings are black and rice-size whereas rat droppings are bean-size. Other signs of a rodent problem include:

• Burrows – fresh diggings around foundations and into walls 

• Runs – dust free “pathways” along otherwise dusty walls and floors

• Smudge Marks – greasy film left by fur often associated with runs

• Gnawing Marks – on wood, concrete or other material

• Sightings – mice in daytime are common, rats in daytime indicate overcrowding

How do I control the infestation?

The first step in any rodent control program is to survey the area to determine the source of the rodents, the extent of their population, and the source of their food. The most important control measure is good sanitation.

• Rodent proof buildings by sealing outside openings where rodents can enter with course steel wool and placing sheet metal around pipes and electrical conduits.

• Eliminate harborage sites through good housekeeping. This includes storing food and other items off the floor. Remove all sources of food and water. All water leaks should be properly repaired and spills cleaned up. Rodent-proof storage containers should be used. Attention to garbage handling and disposal is vitally important. Garbage provides rats with both food and water in residential areas and it is equally important in commercial food handling establishments and rural areas. Garbage should be wrapped in plastic bags until final disposal in tight containers. Metal garbage containers should be rust resistant, water tight, adequate to store garbage between collections, have tight fitting lids and a recessed bottom, and be located on a concrete base or raised off the ground.

• Control existing populations through traps and rodenticides. Make sure to use the correct trap (rat traps for rats, mouse traps for mice). Be sure to place enough traps (1-2 m (3-6ft) apart for mice, 7-10 m (23-33ft) apart for rats) in areas of high rodent activity. Traps should be placed where they are inaccessible to children and pets. Clearly label any bait that is poisonous. 

• Glue boards are very effective against mice. Mice become entangled in the glue when they run over the boards and then die of suffocation. They are the method of choice in homes and other sensitive locations where toxic baits are a concern. Should the glue from a glue board contact the fur of a pet or the skin of a child it can be removed with mineral or vegetable oil. Traps and glue boards should be checked daily.

• Rodenticides are poisonous to other animals and humans. Always read and follow the label directions and precautions.

How can I protect myself?

Handle dead rodents with gloves and dispose in household garbage. Dispose of garbage in tightly sealed bags. Wash your hands with soap and running water after handling traps, poisons or dead rodents.

For further information

Pest Management Regulatory Agency, www.pmra-arla.gc.ca

Pest Control Canada, www.pestcontrolcanada.com

Source:

Durham Region Health Department