Whisper birds were avians native to the moon Yavin 4. They were known for their radiant plumage and gained their name due to their seemingly noiseless flight. They used their dexterous tongue to emit their sweet, low-pitched song or call. Whisper birds were at home in the trees and water of the jungle moon. They would go quiet when they desired food, which consisted of fish and weeds, as well nectar funnels that grew on vines. As with other small animals native to Yavin 4, they were prey to stintarils and other predators. Introduced whisper bird populations existed on Coruscant and Null.