Bioacoustics – Current Research Focus at Año Nuevo

The UCSC Bioacoustic field team is led by graduate student Caroline Casey. Over the course of four breeding seasons, the study required enormous effort to record and mark all the males in the colony, observe their interactions, obtain recordings free of background noise, and conduct playback experiments within the large, dynamic colony.

Acoustical analysis of each recorded voice and the creation of digital images allowed each male to be compared to his peers. “Anybody who’s studied elephant seals knows that their vocal communications are important, but we haven’t known what information is encoded in the vocalizations,” Casey said.

“What we found is that these calls are identity signals. Each male has a unique call, and they learn to recognize the calls of their competitors, so they know how to respond during contests.”

When they recognize the call of another male, they know whether to attack or flee depending on their previous interaction. A male who has lost a fight to another male will even flee from a playback of a recording of the victorious male’s call.

This year (2018), the research continues as researchers attempt to discern whether this memory and response persists from year to year. In the future, the researchers hope to turn some of their attention to the vocalizations of females and their pups. So stay tuned for more groundbreaking research out of Año Nuevo….