Quantum Units Education®

1. Norway rats, Rattus norvegicus, sometimes called brown or sewer rats, are burrowing rodents that are larger than roof rats. Their burrows are found along building undations, beneath rubbish or woodpiles, and in moist areas in and around gardens and fields.

2. Roof rats, R. rattus, sometimes called black rats, are much larger than Norway rats. Unlike Norway rats, their tails are longer than their heads and bodies combined. Roof rats are agile climbers and usually live and nest above ground in shrubs, trees, and dense vegetation such as ivy.

3. Because rats are active throughout the year, periodically check for signs of their presence. Once rats have invaded your garden or landscape, unless your house is truly rodent proof, it is only a matter of time before you find evidence of them indoors. Experience has shown it's less time consuming to control rodents before their numbers get too high, and fewer traps and less bait will be required if control is started early.

4. While rats are much larger than the common house mouse or meadow vole, a young rat is occasionally confused with a mouse. In general, very young rats have large heads and feet in proportion to their bodies, whereas those of adult mice are proportionately much smaller.

5. Rats, like house mice, are active mostly during the day. They have excellent eyesight and they also have keen senses of hearing, smell, taste, and touch.

6. Among the diseases rats can transmit to humans or livestock are murine typhus, leptospirosis, salmonellosis (food poisoning), and ratbite fever. Plague is a disease that both roof and Norway rats can carry, but it is more commonly associated with ground squirrels, chipmunks, and native woodrats.

7. House mice are medium sized rodents with relatively small ears and large, black eyes. They weigh about 1/2 ounce and usually are light brownish to gray. An adult is about 5 to 7 inches long, including the 3- to 4-inch tail.

8. In a single year, a female mouse may have 5 to 10 litters of about 5 or 6 young. Young are born 19 to 21 days after conception, and they reach reproductive maturity in 6 to 10 weeks. The life span of a mouse is usually 9 to 12 months.

9. Trapping is the safest and most effective method for controlling rats in and around homes, garages, and other structures. Because snap traps can be used over and over, trapping is less costly than poison baits but more labor intensive.

10. Dogs and cats will catch and kill mice and rats. These pets have proven effective in controlling rodent infestations.

11. Prevention is the single-most important measure for effective rodent control. By reducing the availability of food and water and making building access difficult, you can help make your school/home less desirable to rodents.

12. If good sanitation and preventive measures are not enough to keep out rats and mice, more aggressive controls may be needed. Physical control (trapping) is the next step, with chemical controls (usually baits) as the last resort.

13. Exclusion is the least successful and temporary form of house mouse control. Build them out by eliminating all gaps and openings larger than 1/4 inch. Stainless steel scouring pads make a good temporary plug. Seal cracks in building foundations and around openings for water pipes, vents, and utility cables with metal or concrete.

14. If using glue boards, place them along walls where mice travel. Don't use them where children, pets, or desirable wildlife can contact them. Don't use glue boards to catch deer mice (Peromyscus species), as captured mice often urinate and defecate while stuck to the trap, thus increasing the risk of your exposure to hantavirus.

15. Anticoagulants are blood-thickening drugs that cause an animal's blood to clot, damaging capillaries and resulting in internal bleeding that is fatal. These active ingredients are used at very low levels and the onset of symptoms is delayed, so the rodent doesn't avoid the bait because of its taste or the onset of illness.

16. Anticoagulants fall into two groups-the older 'first generation' compounds; warfarin, chlorophacinone, and diphacinone, which require a rodent to consume multiple doses over a period of several days; and the newer 'second generation' compounds brodifacoum, bromadiolone, difenacoum, and difethialone, which can be fatal after a single feeding.

17. Rodents are easily frightened by strange or unfamiliar noises and regularly repeated sounds. Ultrasonic sounds, those above the range of human hearing, have very good effect in rodent control, because they are directional and don't penetrate behind objects.

18. All rodenticide baits must be used carefully according to the label directions, which have become more specific and more restrictive.

19. Live traps are preferred, because trapped rodents can be released elsewhere. Releasing rodents outdoors is recommended, as removed rodents will decrease the rodent population. Because neither the roof rat nor the Norway rat is native to the United States, they must be released at least 100 yards for the trapped area.

20. Glue traps, which work on the same principle as flypaper, aren't recommended for controlling rats, as they are much less effective for rats than for mice.