Puka are a species of mammal native to the smallest continent of the planet Eriu. They resemble a ferret and are three to four feet high on their hind legs. They are considered inquisitive and sociable, and the species has shown itself as capable of learning simple tasks such as opening doors and turning on lights.
Morrigan's human slaves domesticated Puka and they grew in popularity as entourages that traveled with Morrigan and her Underlords were introduced to them. Pet Pukas can now be found on planets far from Eriu. They can fetch small objects and carry messages. (RPG: "Living Gods: Stargate System Lords")