Blue Whales Just Don’t Know How To Avoid Cargo Ships, Study Shows
Blue whales and cargo ships don’t mix. In fact, scientists say frequent collisions between the whales and giant ocean-going vessels may help explain why blue whale populations remain low despite efforts to protect the endangered species.
Now a new study reveals why ocean-going ships pose such a big threat to the whales: the gentle giants simply don’t know how to get out of the way.
Smart but vulnerable. Like all whales, blues are smart. But since they’re the largest animal on Earth, they’ve never had to defend themselves against “predators.”
“It’s not part of their evolutionary history to have cargo ships killing them, so they haven’t developed behavioral responses to this threat,” Dr. Jeremy Goldbogen, assistant professor of biology at Stanford University and a co-author of the study, said in a written statement. “They simply have no compelling response to avoiding these dangerous ships.”
How do blue whales respond to oncoming ships? For the study, the researchers used suction cups to attach GPS (global positioning system) devices and dive-logging units to blue whales off Long Beach, Calif., one of the world’s busiest ports.
The researchers observed 20 ships passing by nine whales, at distances ranging from 60 meters to more than 3 kilometers, and analyzed how the whales responded. It turned out that the whales tended not to swim to the side to avoid a ship — but to make a slow dive.
“We also observed the slow-dive response, or the sinking behavior, during tagging,” Dr. Megan McKenna, a research biologist at the National Park Service and the study’s senior author, told The Huffington Post in a phone interview. “In some cases, after we placed the suction cup tags on the animal, the animal would sort of sink out of our vision, —> Read More