Dumpy is a puffin (presumably an Atlantic Puffin, Fratercula arctica) that The Band comes across on their journey to the Great Ga’hoole Tree. He explains that puffins aren’t very smart, although he is good at fishing and predicting the behaviour of the wind and weather.
Soren, Gylfie, Twilight, Digger, and Mrs. Plithiver meet Dumpy and his family after being blown into the Ice Narrows by a williwaw. At first The Band mistakes Dumpy for a plant-like creature, much to Dumpy’s disgust, but he later lets the band into his ice nest to wait out a storm. Once the storm dies down, Dumpy informs them of good flying conditions and how to get to the Sea of Hoolemere.
While flying out to preform duties in the Northern Kingdoms, the chaw of chaws, escorting Dewlap, come across the puffin family again during Puffinflockin-in the nocken, when young puffins, known as pufflings, learn to fly for the first time. Dumpy invites the owls back to his nest, where his mate Tuppa is sorting out her catch of fish. When Tuppa sees Dewlap, she feeds her a fish and starts treating her like a chick. Appalled, Little Dumpy, Dumpy’s son, flies out of the nest. Dumpy and Tuppa seemed relieved that Little Dumpy has left the nest, even though Tuppa was crying over her chicks leaving only a moment ago.
Dumpy is mentioned by his son, Dumpy the Fifteenth, as he thought about whom he should tell what he saw in the ice cave to. Dumpy's son thought that he shouldn't tell him, because he is too stupid. Possibly, Dumpy joins in the Dump Brigade, led by his son and fights alongside the Guardians of Ga’hoole against the Pure Ones.
- Dumpy might be the descendants to the Puffowl since he said that he knew, heard, or saw hagsfiends. Also, he is too smart to be just a puffin, and since a Puffowl is a bizarre combination of a Snowy Owl and a puffin, they must be smarter then just a puffin.
- Dumpy is the fourteenth line of his generation.
- The Echidna may have been a replacement for Dumpy in the movie Legend of the Guardians: The Owls of Ga'hoole.