This forecasting tool aims to keep ships and blue whales from colliding

A new forecasting tool will help scientists predict blue whale traffic, as the ocean behemoths make their annual migration.

The tool allows researchers to post online maps showing likely “hot spots” for blue whales that will help ship captains avoid collisions with the animals.

“We can both see where they go and when they go,” said Elliott Hazen, a research ecologist with the National Marine Fisheries Service, who developed the forecasting program. “We can take their movements and combine that with remotely sensed oceanographic data, to find out not only where they go, but also some of the oceanographic conditions that trigger that.”

When the whales travel up the California coast, they navigate a marine highway of shipping vessels, fishing boats and cruise liners. There are several reported ship strikes per year, but there may be many more than that, said Helen Bailey, a research associate professor at University of Maryland, Center for Environmental Science, who coordinated the forecasting process

“We’re probably underestimating the number that have been hit by ships, because they sink and don’t float,” Bailey said.

Blue whales are the largest creatures ever to live on the planet, with silvery bodies that can grow more than 80 feet and up to 165 tons. But there are just under 2,000 of them, and their numbers aren’t growing, Bailey said.

In the past, scientists relied on maps of tagged blue whales to show the routes the animals had traveled. This is the first time they can project where they’ll be in the future, Hazen said, which will allow regulators to impose closures or ship speed limits in areas identified as whale hot spots.

The data, posted online, can also help ship captains to avoid the whales proactively.

J. Kip Louttit, executive director of the Marine Exchange of Southern California, said such voluntary measures are a better way to keep whales safe than closing shipping lanes. Armed with the information, captains are likely to stay out of the whales’ way, he said.

“The shipping community welcomes, embraces and wants any and all information,” Louttit said. “Nobody wants a whale strike. It can damage the ship, it can damage the rudder, it can damage the propeller. It’s bad for the environment. People who go to sea tend to like the sea. You don’t want to damage whales or fish.”

deborah.brennan@sduniontribune.com

Brennan writes for the San Diego Union-Tribune