Black Rat - Rattus rattus

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Black Rat - Rattus rattus vs Bush Rat - Rattus fuscipes

The Black Rat is an introduced species to Australia and a pest to people and wildlife. It is included here to help clarify the difference between it and one of our widespread indigenous rats, Rattus fuscipes the Bush Rat, of which it is often confused.

For a start, Black Rats are seldom black and are commonly colored grey/brown with cream underneath. This is not always the case as the coloration of this species can be quite variable, but from the ones I have seen in NSW, Victoria, Tasmania, SA and WA, the coloration above would by far be the most common. The coloration of the Australian Bush Rat is reasonably consistent, varying only slightly in lighter or darker shades of their fur. There is another similar colored introduced rat called the Brown Rat, Rattus norvegicus, but in Australia it is usually restricted to sewers and other man-made structures along waterways, so is less likely to be encountered in bush habitats, and unlike the Black Rat that is widespread around Australia and usually found within a 100 km or so of the coast.

The Black Rat is long and sleek with a tail obviously longer than its head/body length. The Bush Rat is more chubby with a tail the same length or shorter than the head/body length. You can usually spot the tail difference even with a swiftly moving animal.

The Black Rat is an excellent climber with fingers and toes that are able to firmly grasp things to aid it in this task. They use this ability to get into your roof, raid fruit trees and plunder birds nests. The native Bush Rats will rarely climb off the ground (apart from a succession of flat surfaces like rock ledges) and are not capable or interested in climbing more than a metre and only then if easy to do so.

There are many other differences between these rats, but these require a compliant animal for closer inspection, some of which may be seen by comparing the photos of each species above. The Black Rat is very intelligent and a highly destructive predator, feeding on just about anything it can get hold of (living or dead); the Bush Rat on the other hand is mainly vegetarian, although at times it will feed on some soft bodied insects. The only benefit of a Black Rat is they will kill and eat another introduced rodent, the smaller House Mouse, Mus musculus, but it will also prey heavily upon most small native animals (particularly their young) and have devastated wildlife throughout the world on many small off-shore islands. So if you catch one, it may look cute, but please don't let it go!

I should like to add that the native Bush Rat shown in some of the photographs above, was accidentally killed when it climbed into the engine compartment of my car. For more information about this rat, please refer to Mammals - Bush Rat

Mitchell's Hopping-mouse - Notomys mitchelli

I have only seen one of these native mice, and that was in the mallee (its preferred habitat) not far from Mt Ridley (approximately 70 km NNE of Esperance). A lucky sighting as I caught it in my headlights when returning home late one evening along a bush track, however its appearance and method of locomotion were unmistakable. As can be imagined I was not only surprised, but delighted to have see it.

It is considerably larger than a house mouse and with a much longer tail, but nearly half the size of the introduced black rat. It commonly stands on its haunches like a miniature kangaroo and has a fast low hopping gait. It eats seeds, insects and herbaceous vegetation. Home is several deep burrows often well separated from each other and shared by related individuals. A photograph can be viewed here: http://museumvictoria.com.au/bioinformatics/mammals/images/mitclive.htm

Bush Rat - Rattus fuscipes

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Bush Rat - Rattus fuscipes

Coastal heath is this attractive rats preferred habit where it builds a network of tunnels to nest and breed, suitable rocky habitat with deep recesses are also colonised. A sandy mound of excavated sand is usually all that is seen of this animal as it is shy and almost exclusively nocturnal. Unlike the introduced Black Rat (mostly brown colored) it is not a good climber and usually will not invade houses, preferring its bush habitat.

The Bush Rat will eat insects, various types of vegetation and fungi. Consequently, and unlike the more carnivorous introduced rats, the Bush Rat is a very clean animal. It has attractive long soft fur giving it a chubby appearance and the tail is a little shorter than its head/body length (the introduced Black Rat, Rattus rattus by comparison has a very long tail of around 11/2 times the head/body length).

Bush Rats although once common have been drastically reduced from cat and fox predation. It is also preyed upon by the larger (to 2 metre) Dugite (snake) that will enter their tunnel network and even over-winter there too. Motor car engines are also not safe places for these rats, where the deceased one in some of the photographs above was accidentally killed.