The Quor'sav were a warm-blooded, avian/monotreme species whose average height was about 3.5 meters, Quor'savs were native to the planet Uaua. When a group of colonists arrived on Uaua, the Quor'sav initially welcomed them. However, when a virus that had been carried by the colonists to the planet began infecting the Quor'sav, the avians were forced to stop all immigration until a cure could be found. Since this time, the Quor'sav have been reluctant to trust other species, especially mammalian races.