From my camera trap in Melbourne suburb, I’m not sure if I caught one rat species or two.
Two rats have very different colours, one clearly brown and one clearly black.

Both rats together

Brown rat

Black rat

Other night animals on camera trap are pussy, ringtail and brushtail.

My tree, not my cat

Ringtail

Brushtail

Will post day birds from camera trap here later. I’m not sure if I caught a little wattlebird or if they’re all red wattlebirds.

mollwollfumble said:

From my camera trap in Melbourne suburb, I’m not sure if I caught one rat species or two.
Two rats have very different colours, one clearly brown and one clearly black.

Both rats together

Brown rat

Black rat

Other night animals on camera trap are pussy, ringtail and brushtail.

My tree, not my cat

Ringtail

Brushtail

Will post day birds from camera trap here later. I’m not sure if I caught a little wattlebird or if they’re all red wattlebirds.

Tail longer than body, Black rat.

mollwollfumble said:

From my camera trap in Melbourne suburb, I’m not sure if I caught one rat species or two.
Two rats have very different colours, one clearly brown and one clearly black.

Both rats together

Brown rat

Black rat

Other night animals on camera trap are pussy, ringtail and brushtail.

My tree, not my cat

Ringtail

Brushtail

Will post day birds from camera trap here later. I’m not sure if I caught a little wattlebird or if they’re all red wattlebirds.

See if you can measure the lengths of the rats’ tails and compare those measurements to the length of their bodies. The tail of Rattus rattus (black rat) is at least as long as, and usually longer than, its body, whereas the tail of Rattus norvegicus (brown rat) is shorter than its body. R. norvegicus is much more common in urban areas, especially the region you’re in (Moorabbin.) They might be different species, but they’ve displaced almost all other rats in urban Melbourne, so it’s unlikely.

btm said:

See if you can measure the lengths of the rats’ tails and compare those measurements to the length of their bodies. The tail of Rattus rattus (black rat) is at least as long as, and usually longer than, its body, whereas the tail of Rattus norvegicus (brown rat) is shorter than its body. R. norvegicus is much more common in urban areas, especially the region you’re in (Moorabbin.) They might be different species, but they’ve displaced almost all other rats in urban Melbourne, so it’s unlikely.

Ta.
For the black one here the tail is at least as long as the body.
For the brown one here … see below.
I couldn’t see the exact tip of the tail on any photo.
Perhaps I’ll try again some other day.

There’s something about differing ear sizes as well, I think. The ears of the black rat are supposed to be larger than those of the brown rat. I don’t see any obvious difference in ear size, here.

The image below is of the brown one with a tail at least 15% longer than the body. So ??

That looks like a filigree Siberian hamster.

fsm said:

That looks like a filigree Siberian hamster.

Manuel?

It’s all very confusing. Supposedly the three differences between black rats (rattus) and brown rats (norvegicus) are colour, tail length and ear size.

Brown rats have shorter tails and smaller ears.

Black brown rats exist (as escaped pets) but, weirdly, black brown rats have thinner longer tails like true black rats.

On the flip side, brown black rats exist (wild in Japan) but, also weirdly, have smaller ears like true brown rats.

Colours of black rats.

Colours of brown rats.

Aha!

So, according to Austrlian museum website https://australian.museum/learn/animals/mammals/black-rat/ the black rat in Australia “Despite its name, the Black Rat is usually brown or grey.”.

It’s important to have an Australian website as a reference because it may not be true overseas.

So they’re both black rats, despite the big difference in colour.

mollwollfumble said:

Aha!

So, according to Austrlian museum website https://australian.museum/learn/animals/mammals/black-rat/ the black rat in Australia “Despite its name, the Black Rat is usually brown or grey.”.

It’s important to have an Australian website as a reference because it may not be true overseas.

So they’re both black rats, despite the big difference in colour.

About time you got it.