By most standards, rats are considered pests or vermin. They can be very destructive to crops and property. Rats can quickly overpopulate when they live in a place where they have no predators, such as in certain cities, and their numbers can become hard to contain.

Rats have a significant impact on food production. Estimates vary, but it is likely that about one-fifth of the world's total food output is eaten, spoiled or destroyed by rats. It is interesting to note that about one-third of the food purchased by humans is thrown away as garbage in certain areas.

Information and Habitat

Norway rat (Rattus norvegicus) - is 13-18 1/2 inches total length, with its tail being shorter than its head and body combined. An adult Norway rat weighs about 3/4 to 1-1/4 pounds. It is mostly brown, with a lighter colored stomach. The tail is semi-naked and darker above than below, giving it a two-toned effect.

Roof rat (Rattus rattus) - is also 13-18 1/2 inches total length, with its tail being longer than its head and body combined. An adult roof rat weighs about 3/4 to 2/3 pound. It is mostly black with some gray below, although there are some variations. The tail is also semi-naked, but of one color.

Threat

Rats can carry over thirty different diseases dangerous to humans, including Weil's disease, typhus, salmonella and bubonic plague. Black rats are suspected to have had a role in the Black Death, an epidemic which killed at least 75 million people in Europe, the Middle East, and Asia in the mid-late 14th century. Because rats are nocturnal, daytime sightings of rat activity can mean that their nesting areas have been disturbed or, more likely, that there is overpopulation of them in the local area. It is typically at this point that vermin control measures tend to increase.

Rats often chew electrical cables. Around 26% of all electrical cable breaks are caused by rats, and around 18% of all phone cable breaks. Around 25% of all fires of unknown origin are estimated to be caused by rats. Rats, particularly roof rats (Rattus rattus), can enter the attics of homes where they mate and nest. This problem occurs commonly in coastal, temperate climates and affects even the cleanest, well-kept homes.

For more information on common pests, please visit buginfo.com