Over the years, many popular magazines and movies have featured stories about rodents. In this age of information technology, good information can be transferred quickly. On the other hand, the Internet & poorly researched articles can serve to quickly misinform the public.

The following are myths, misconceptions, or half-truths commonly heard from people about the rodent in their neighborhoods.


MYTH: One, Two... Nine... Rats Per Person

FACT: No one knows how many rats par capita exist in any city. It probably ranges from zero to several dozen rats per person in any given area. It is only safe to say we know there may be dozens or millions of rats in any one city, depending on many urban environmental factors.


MYTH: Sewers Rats and Wharf Rats are Different

FACT: Norway rats may be called "sewer rats", wharf rats, river rats, alley rats, house rats and barn rats. Some people mistakenly believe there are different "varieties" of rats according to these names. Roof rats may also be subject to similar misunderstandings.


MYTH: Rats Must Gnaw or Their Teeth Will Continue To Grow

FACT: Not true. Rats maintain incisor growth end sharpness by grinding the lower incisors against the uppers. They do not need to gnaw on objects, although they will supplement tooth grinding with object gnawing.


MYTH: Rats as Big as Alley Cats

FACT: The Norway rats that inhabit sewers are not necessarily any larger than their cohorts inhabiting an alleyway or park bush above ground. In fact, they could just as easily be smaller. In extensive studies of the sewer rats of London, the heaviest rat captured weighed 15 oz. But larger rats have been recorded in and around farms. The heaviest Norway rat ever reported was 1.8 lbs.


MYTH: Rats Have Become "Immune" to Most Rodenticides

FACT: It is true that many rats and mice are now resistant to the first-generation anticoagulant rodenticides. Luckily, however, so far most rats are still quite vulnerable to the second-generation anticoagulants.


MYTH: Mother Rats Teach Their Babies to Avoid Traps and Poisons

FACT: Young rodents avoid objects and food items simply by following their mother around just after being weaned. If the mother rat bypasses a trap or bait, a young rat may also bypass these items. The mother rat likely passed the baited traps due to more attractive resources further along or because she is fearful of any new objects.


MYTH: Rats are Aggressive and Attack Children and Pets

FACT: Some rats, if provoked and cornered, will fight their way out of the confrontation, as will many wild animals. But most rats do not outwardly attack humans. Young babies, bed-confined elders, and the homeless sleeping in doorways and alleys, however, are occasionally bitten by unprovoked rats. Most likely these individuals fall asleep with food residues on their hands or faces, and foraging rats attempt to lick or chew the food residues off the sleeping individual.


MYTH: Sewers Rats Are Mutated - Blind and Unusually Large

FACT: The Norway rats that infest sewers are neither blind nor unusually large.


MYTH: Construction Causes Rats to Flee Sewers

FACT: Not true. Rats are, for the most part, unperturbed by above ground street construction practices. In fact, they will not leave a suitable sewer system unless their burrows are directly excavated.


MYTH: Rats Transmit Rabies

FACT: The Norway rat & house mouse are not considered important reservoirs for the rabies virus in the U.S. Rat bites do not necessitate the victim being treated for rabies as is commonly done for dog, cat, bat, fox, raccoon and other wild animal bites.

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