Some poor fools once tried to mine or colonize the world where Riddick is marooned.
The desert dogs are far too much like real dogs to be plausibly native to the same ecosystem that produced the scorpion-beasts or the winged scavengers. However, they'd make sense as the feral descendants of actual Earth hunting or guard dogs, which were brought there by human settlers and outlived their former masters, adapting to the planet's harsh conditions over many generations.
