Beldons are the largest animals in the galaxy, from 800 meters to 1000 kilometers in length, and appear as giant gas bags which ride the currents in Bespin's atmosphere. Several theories exist which claim that beldons give off natural tibanna gas and are therefore protected by law. They are rather gentle animals which feed off algae and nutrients that are suspended in the clouds.

Rawwks are small, 0.3 to 0.7 meter wingspans, bat-like creatures that fly among the clouds of Bespin. This is the one animal which is most likely to be seen by visitors to Cloud City due to the fact that they inhabit open girders and abandoned air chutes. Also, rawwks appear to have a symbiotic relationship with beldons. The beldons provide the rawwks with large, moving nests while the rawwks clean them of any excess algae and provide an early-warning system by fleeing at the sight of a velker.

Velkers are leathery, V-shaped flyers that are 200 to 350 meters wide and are the top predator of Bespin. They primarily feed on beldons, but have been known to attack cloud cars. There have been a few reports of attacks on Cloud City. This has been attributed to the velkers mistaking Cloud City's electromagnetic field for an immense beldon. Velkers resemble fixed-wing aircraft when in flight, have rather long claws, and rows of mouths lining their bellies.