The sea chicken is a character who was used by SpongeBob to cure a patient's illness. It only appears in the episode "Code Yellow."
The sea chicken is a chicken with white feathers It also has a yellow-orange beak and feet and black claws. It has a red comb on the top of its head, and wears an air helmet very similiar to Sandy's. It makes a squacking noise.
While SpongeBob tries to cure the catfish, who is suffering from a sore throat, he asks for a "medical sea chicken." The purple doctor grabs the sea chicken from the first aid kit, and SpongeBob plucks a feather from the chicken, who then flies out of the window. He then uses said feather to tickle the catfish, who coughs up the keys he swallowed.