Plurp

Coo Coos are hen-like creatures only appearing in Super Mario Sunshine who appear in Bianco Hills where they fly around randomly and drop splotches of Goop whenever they get near Mario. They can be jumped on or sprayed three times to be defeated. They later appeared in episode three of Pianta Village dropping fiery Goop.

They resemble large chickens with two beady eyes, with a star around one. Their appearance is possibly based from the Booty Birds from Donkey Kong Country 3: Dixie Kong's Double Trouble!.

Trivia

 * Cluckbooms, enemies that look similar to Coo Coos, appear in Super Mario Galaxy, and its sequel, Super Mario Galaxy 2. Their method of attacking Mario is by dropping Bombs on him, similar to a Coo Coo's method of dropping Goop on Mario.
 * Their name is based on Cuckoo, a phrase a Cuckoo Clock makes.