The seagull is a minor character on Oobi.
The seagull lives near the local fishing pier. It makes two short appearances in the "Fishing!" episode. When Oobi and Grampu go fishing by the shore, Oobi notices the seagull landing on a rock. It flies away for a while. Oobi thinks that he and Grampu are alone, then realizes that the seagull flew back. He says "Just Oobi and Grampu...and seagull."
The seagull has two hands for wings and a head made from two thumbs (like a bird shadow puppet). It has reddish-orange eyes, an orange beak, and spiky white feathers on its head.