The stuffed bear that Julian Bashir has kept since early childhood, whose repair at the age of five he regards as his first act of surgery.
Kukalaka is Bashir's teddy bear. In the Deep Space Nine episode The Quickening, he tells his patient Ekoria that when the bear's leg came apart and his mother wanted to throw it away, he sewed it up himself, and went on mending it for years. He admits a little sheepishly that he still has it.
The bear plays a part in In the Cards. Bashir's former girlfriend Leeta has kept Kukalaka since they parted, and when Jake Sisko and Nog need a favour from the doctor, his price is the bear's return. Nog slips into Leeta's quarters and takes it while she sleeps.
Kukalaka is mentioned again elsewhere in the series, an affectionate reminder that the station's brilliant doctor has an unguarded, childlike side.