There are three main pest species of mice and rats in Australia, they are:-

1. The Brown Rat (Rattus norvegius).    Other common names - The common rat, sewer rat, brown rat, and water rat.

This animal will eat all human and animal foods including stock feed like grain, pelletised foods etc.    It needs access to a regular supply of water and is susceptible to liquid baits.

It adapts well to a rural outdoor existence and will live outside in the summer months but indoors during the winter months or may live inside all the year round.    Lives in burrows and will dominate the Black Rat, (Rattus rattus), in situations of co-existence.    Its territory is around 40 - 50 metres from home base and is defended according to a "pecking" order.    They are, however, very neophobic (fearful of new things).

In summary the Brown rat prefers:-

Burrows,

Swims well,

Occurs in sewers, creeks and canals,

and prefers rural areas.

2. Black Rat (Rattus rattus).    Also known as the ship rat.

This animal prefers vegetables and fruits in preference to dry foods and consequently is less dependent on a regular water supply due to the moisture content of its preferred diet.    They live mainly indoors and around ports and harbours.    They are great climbers and can cross from building to building or ship to ship on cables, ropes and suchlike.    If forced to live outside they prefer vines and trees in which to nest, rather than burrows.    They can infest ships very quickly and would be a prime target for quarantine officers.    Their home range is similar to that of the Brown Rat.

In summary the Black Rat:-

Does not burrow.

Is a very good climber.

Is a poor swimmer.

Is rarely found in sewers and prefers high places.

Both rat species tend to sit and eat from a single food source.

3. House Mouse (Mus domesticus).   Sometimes erroneously called the field mouse.

Mice are omnivorous to such an extent that they will eat virtually any food source and can survive on the moisture extracted from grain but will need a water supply if they are feeding on cereals.    They tend to eat small amounts of foods at various locations and are curious and exploratory feeders with a territory of some 3 - 10 metres from the nest.    Mice are not as neophobic (fear of new things) as rats.

In summary Mice:-

Make burrows and nests.

Are found in most places, indoors and outside, and do not occur in sewers (Turtles, which are found in sewers, will eat them).      

General

Their sight is poor and have difficulty in determining images, creating a heavy reliance the sense of touch, but their sense of smell is extremely keen and can detect odours in foods which make the choice of baits important.    They also have a very keen sense of taste and can associate sickness with tastes and smells which would make it important to vary the bait type.    They have likes and dislikes and can develop "bait shyness".    Their sense of hearing is also acute which extends into the ultrasonic.    Touch is extremely sensitive, using their whiskers and hair to "feel" their way around at night.

All these species have a dominant male i.e. "King Rat" who will spoil baits to ensure rivals don't eat them.

Things to look for if you suspect a rodent problem:-

Dead bodies.

Burrows.

Runways, rub marks and grease smears usually on vertical surfaces.

Evidence of gnawing.

Tracks and droppings.

Nests.

Smell.

Strange noises, particularly at night.

Food disappearing.

Watch your own animals reactions.

The preceding information is provided with the kind permission of

Adelaide Pest Control,

North East Road,

Walkerville,

SA 5081 

Ph. 08 8344 8181.