Bunyip

Bunyip was a local word for dragon and sea serpent-like creatures that lived in the Australian outback. The creatures lived in long underground caverns, and moved around without being detected from above. With dragons and people eating up the local game, the bunyips resorted to snatching luckless humans away from the party with Temeraire, as they flew across the continent in search of a stolen egg.

The bunyips displayed a high level of intelligence, by trapping Temeraire in quicksand by diverting underground rivers while he slept, and then attacking the less formidable humans and Caesar en masse.

Temeraire was never able to learn their language, but the groups formed and uneasy truce by leaving kangaroos at the mouths of bunyip holes as a peace offering.