Australian Shepherd may only have two pure colours (red and black), its undercoat gives this breed a multitude of possible colour combination - black, red, red merle and blue merle. We'll explain more about what each of these means. 1. Black: These Australian Shepherds have mainly black fur, which can appear matte or shiny depending on their undercoat. For instance, if they have a reddish undercoat, the fur will appear matte.2. Red: Red fur allows for more nuances than black - from a light pinkish shade too much darker colours close to aubergine. Red Australian Shepherds' coats may change colour as the season's change and they shed. Australian Shepheard Getty Images3. Blue Merle: The blue merle coat is probably the most common and offers even more nuances than the red coat. It's a mixture of black and white fur which gives this coat a bluish appearance. The Australian Shepherd may have several black patches or even be almost entirely black and still be considered to have a blue merle coat.3. Red Merle-Brown: Like the blue merle, the red merle offers a wide variety of colours. It is a mixture of brown and white fur which gives these dogs their reddish coat. They can also have patches, like the blue merle and like the red Australian Shepherds, these dogs' coats can change with the seasons.