Rodents
Rats and mice are, next to man, the most successful animals on earth in terms of abundance and diversity. Man has unwittingly help their spread throughout the word by exploration and his own success. However, they have in some circumstances become his worst enemy.
Billions of dollars each year is lost by contamination of food by rodent droppings, urine and hair. Rodents destroy much more food than they could possibly eat, and their chewing habits have been responsible for causing fires.
They are so prodigious that within a year a rat can have between thirty and eighty offspring, depending on the species, one pair could generate fifteen thousand rats in their life span. Rats can squeeze through a hole the size of a 20 cent piece, fall 20 metres with no injury, tread water for 3 days, eat all sorts of food and survive an atomic bomb test.
Roof Rat
THE ROOF RAT
(Rattus rattus) or black rat/ship rat is the rat responsible for the
Black Plague and the death of millions of people from its flea. Its
abilty to climb spread it throughout the world by climbing ships hawsers.
It likes to live in trees and roofs of buildings.
Norway Rat
THE NORWAY RAT
(Rattus norvegicus) or brown/sewer rat likes to burrow (unlike the roof
rat) and prefers to live near water and damp places. It has a thicker
body, shorter tail and smaller ears than the roof rat.
House Mouse
THE HOUSE MOUSE
(Mus domesticus) Mice are a much bigger economic problem than rats in
Australia, with population densities reaching 32,500 per hectare in
plagues. They need much less free water than rats, with a shorter gestation
period and at forty-two days, are at nearly half the breeding maturity
of the Roof rat.
Mice are distinguished from young rats by smaller heads and feet, larger ears in proportion, and much longer tail.