Brave Little Whale - Deirdre Kiernan

Bubbly is a little whale who dreams of adventure. He looks forward to the day when he could rejoin his pod (a family of whales). But one day his mother, Petronella, is captured by a whaling ship! It is up to Bubby to find her but where should he start? With an adventure-driven starfish named Captain Sorely, to guide him, they set forth on the search of Bubby's mother.