Blue whales have been singing less, and it could be a bellwether of climate change. Warming oceans affect the availability of their only food source, krill, and according to a study published in the journal PLOS One , there's a correlation between blue whale vocalizations and their food supply.

Deep silence

The study tracked over six years of acoustic monitoring in the central California Current Ecosystem and found patterns. And during those years, blue whale sounds decreased by approximately 40%.

"We don't hear them singing," John Ryan, a biological oceanographer at the Monterey Bay Aquarium Research Institute and the lead author of the study, said to National Geographic . They are "spending all their energy searching." There's "just not enough time left over" for singing, and

See Full Page