From Creatures Wikia
Sahara Norns are adapted to the life in the desert and feel comfortable in this climate. There is, however, no relation to the Hebe Norns of C2. They use food resources more efficiently than normal Norns, utilizing garbage as a food source without getting sick. They can also eat little animals. They can get bored pretty easily, too, if there aren't any toys around to play with.
The Sahara Norns' pregnancy is shorter than for normal norns. Although they feel comfortable in the Desert Terrarium, they also like to have a stroll through the ship now and again.