A pair of local biologists picked up a chorus of holiday humpbacks on their underwater microphone earlier this month.

Local marine biologists and whale expert Jeff Jacobsen said that he and local biologist Jessie Bunkley recorded more than 10 minutes of the whales singing the same song 12 nautical miles off the coast of Eureka on Dec. 2.

“A winter song from another species, another realm,” Jacobsen said. “You’ll hear a chorus of two, probably three humpback whales singing the same song, but not in synch.”

Jacobsen, the same expert who recorded the calls of rare transient orcas near the Samoa Peninsula in June, said that the humpback song is complex.

“It gets rather wild!” he said. “The song has several themes, each consisting of a phrase that is repeated. Each phrase has its own units that mostly stay the same throughout the phrase.”

Jacobsen said the recorded whales are males transitioning from the feeding season to the breeding season.

“Only males sing,” he said. “They all sing the same song and the song slowly changes during the singing season all across the Pacific Ocean: Mexico to Hawaii to Japan. This same pattern repeats in all ocean basins, and in some places one population switches to another population’s song within a season.”

Jacobsen said that the whales have been observed off the Humboldt coast for more than a month, and that by January, they will be in their southern breeding area between Cobo San Lucas and Costa Rica.

“When they return in the spring, some still will be singing,” he said. “Then all songs go quiet during the summer feeding season when they all make other non-song sounds.”

Jacobsen is encouraging Outpost readers to analyze the recording for themselves and suggested that some even play the music for pets and document their reactions.