In the wild, sea lions are kept busy with hunting prey, caring for young, and swimming about in the great big ocean. In captivity, they have more time to devote to activities like sunning themselves, playing, and rocking out.
Ronan the California sea lion lives at the Long Marine Laboratory at the University of California in Santa Cruz. University researchers have studied Ronan's ability to keep the beat of musical tracks by nodding her head. She seems to particularly enjoy upbeat, jazzy disco numbers.
Ronan was first trained to bob her head to a simple metronome-like sound. Once she figured that out, she was able to find and keep the beat of more complex music all on her own. Previously, this ability has only been observed in parrots and humans.
The research is documented in a paper in the Journal of Computative Psychology and sports the awesome title, "A California Sea Lion (Zalophus californianus) Can Keep the Beat: Motor Entrainment to Rhythmic Auditory Stimuli in a Non Vocal Mimic." Ronan's skill appears to challenge a theory that keeping a musical beat requires vocal mimicry abilities, like parrots display.
Perhaps further research into sea lion abilities will tell us if Ronan is a particularly skilled creature, or if this ability can be found in her brethren as well. If more sea lions are capable of keeping a beat, it may offer bands a useful alternative to employing human drummers. It would probably also be less expensive, considering that sea lions will work happily for fish.