Pest Identification And Information

House Mouse (a.k.a. Mouse, Mice, “Meeses”)

The House Mouse is the most commonly encountered  and economically important rodent pest. They not only are a nuisance but also damage and destroy materials by gnawing, eating and contaminating stored food. They are also of human health importance as vectors of disease. The most threatening disease spread by mice is Salmonella, a cause of food poisoning, which is spread by their droppings. They are common throughout the world.

IDENTIFICATION:

• Brown to gray in color with the tail as long as the body.

• Adults weigh about 1/2 ounce.

• Droppings are about 1/8 to 1/4 inch long and rod shaped.         

Biology:

• Live about 1 year and reach sexual maturity in 35 days.

• Have about 6 young per litter (5-8 range) and up to 8 litters per year (every 40-50 days).

• Poorly sighted, seeing about 6 inches clearly  (remember 3 blind mice....?).

• Can survive on 1/10 ounce of food and 1/20 ounce of water per day.  They do not need water if there is a high moisture content in the food.

• Produce about 50 droppings per day.

• Have a bladder but no bladder control and will urinate anywhere and often.

• Spreads disease by contaminating food and utensils with droppings and urine.

Habits:

• Normally live outdoors but will migrate into homes or buildings, typically during spring and fall.

• Prefer to eat seeds or cereal, but will feed on a wide variety of foods.

• “Nibblers,” eating small amounts of food throughout the day.

• Range only 10 to 30 feet once nest is established.

• “Gnawers” since their front teeth continually grow and only gnawing keeps them short.  Rodents are believed to be a significant cause of fires where the cause was undetermined.

• Get around by using their vibrissa or whiskers, sort of like “curb feelers” (because of poor sight). Therefore, if not frightened, will generally be noticed and active along the perimeter areas of rooms etc.

• Excellent climbers and can climb up most rough surfaced walls; they can jump up about 1 ft, and jump down about 8 ft without injury. They can swim, but prefer not to do so.

• Can survive in cold storage facilities with temperatures as low as 14^oF.

• Can and will, run horizontally along pipes, ropes and wires.  

TREATMENT:

• Structure should be thoroughly inspected for openings, which would, or could, allow easy access.  Holes should be plugged, patched, and sealed.  

• Depending on circumstance, rodent equipment may be utilized on the interior and/or exterior depending on the level of infestation, level of control needed, and level of prevention desired.

• Control methods are selected depend on the findings during the inspection phase (generally, a combination of bait, glue boards, and/or traps).

FAQ’s:

“Why is sealing things up so important?”

The long term key to solving a mouse problem is to make sure that mice cannot re-enter the building, just as you would make sure your screens fit properly and would fix any holes in them to keep the mosquitoes out in the summer.  The same applies to mice.

“Where do I look?”

Walk around the outside of the building.  Look at any openings going into your building, such as gas lines, central air, dryer vents, any cracks or holes in the foundation, or loose siding. Don’t think too hard on it, if there is a hole, crack, or gap larger than a 1/4 inch, seal it!

“What do I use to seal it?”

Caulk, sealant, steel wool, “Foam Seal”, screen, concrete, grout, and plaster - anything that will permanently seal the opening.

"Should I use baits or not?"

Like seemingly everything, there are advantages and disadvantages.  After inspection, one should weigh these factors along with where the mice are before deciding whether or not to use rodent baits.  Keep in mind these general factors:

• Bait packets should not be placed in areas that are accessible to children or pets.  Bait should never be left in an open tray, therefore bait stations or unopened packets should be used (mice if present will chew open the packets).

• Baits contain a bittering agent designed to discourage children and pets from even sampling the bait.

• The concentration of active ingredient in most rodent baits is 0.005% (five one-thousandth of a percent) and typically acts as a blood thinner, working well on things the size of mice.  Even if your pet decided to endure the bitter taste, it is doubtful he would consume enough bait packets at a single residence to harm him.

• The antidote (should you ever need one) is Vitamin K for most rodent baits.

SEE ALSO:

    Moles    Shrews