1 Steve: G’day viewers! Someone asked how to identify crows and ravens in Australia. They all look very similar. Terry?
2 Terry: The best way to tell is from their calls. The three raven species have long drawn-out calls. The two crows are quicker, more like quacking.
3 Terry: But remember, crows and ravens are all in the genus Corvus. Despite the different calls, there’s no large biological distinction between any of them.
4 Steve: Crikey! So cawsation does not necessarily imply crow-relation?

There are five species of ravens and crows native to Australia:

• Australian raven (Corvus coronoides).
• Forest raven (Corvus tasmanicus).
• Little raven (Corvus mellori).
• Little crow (Corvus bennetti).
• Torresian crow (Corvus orru).

They all look almost identical, so telling them apart by sight is difficult at best. Here's an Australian raven that I photographed to give you an idea. Imagine all the other species look pretty much just like this.

The main visual distinction is in the colouring of the downy feathers that are normally hidden beneath the flight feathers.

There are two saving graces. Firstly, although their ranges overlap, there are significant portions of Australia where only one of these species is normally found. This, by fortunate chance, includes all of the capital cities. If you see a raven/crow-like bird and you are in:

• Perth, Canberra, or Sydney (where I live): it's an Australian raven.
• Melbourne or Adelaide: It's a Little raven.
• Hobart: it's a Forest raven.
• Brisbane or Darwin: it's a Torresian crow.

There are, however, also regions where all five species can be found. In that case, the best way to distinguish the species is by their calls. This is best illustrated with audio, and BirdLife Australia has an excellent YouTube video which describes and plays the calls of each of the species. The video is also available on BirdLife Australia's website, with a text transcript.

The final point worth emphasising is that although these birds are variously called ravens or crows, there's really no biological basis for separating them into these specific two groupings. The names are essentially arbitrary and based just on what people thought they "ought" to be called. This is the case not only for species in Australia, but all over the world. Generally people have preferred to call larger members of the genus Corvus ravens, and smaller ones crows, but this is not consistent.