Mooseshark is a minor character in Back at the Barnyard. He is a legendary creature with a moose's body and a shark's head with moose antlers. He is revered as a scary creature, but has a goofy personality and voice. He can be summoned if someone says his name three times.
He first appears in "Barnyards and Broomsticks". He is first mentioned in a scary story told by Otis, who is mocked by his friends, who don't believe in Moosehark. In the climax of the episode, when the gang is being pursued by the Piney Woods Witch, Otis gets an idea, and calls out Moosehark's name three times, causing Mooseshark to appear. He successfully intimidates the Piney Woods Witch, causing her to flee.