Whale, ship collisions around the globe could be helped by slower speeds, study shows

Giant ships that transport everything from coffee cups to clothes across the ocean are often so large they can’t tell when they collide with a whale. Now, research out of the Northwest could help these massive vessels avoid collisions with whales around the world.

These collisions are one of the major reasons large whales die, but it’s really hard to study. Often, the whales sink to the bottom of the ocean.

“So most go unreported and often even unnoticed by the people on board the ship,” said Anna Nisi, a University of Washington postdoctoral researcher at the Center for Ecosystem Sentinels. “Even though these events are so difficult to observe, collisions have been reported in all oceans, including areas that haven’t received a lot of studies so far.” 

The problem is well-known and studied in places like the West Coast and the Mediterranean. So Nisi, the lead author of the study, decided to expand that research across the globe. 

The study, published in the journal Science, found whales are at risk all over. 

“Wherever you have coastlines or ports and migratory animals is where you have this conflict,” said Sean Hastings, with the National Oceanic and Atmospheric Administration’s Channel Islands National Marine Sanctuary, off the southern California coastline.

The study mapped whale migration data for blue, fin, humpback and sperm whales. Then, it compared that to global shipping routes. The study found around 92% of whales’ range is affected by shipping. Most of those hotspots aren’t protected by marine efforts aimed at reducing the threat.

“Whales could benefit from expanded protections because current rates of protections are low,” Nisi said.

Whales are incredibly important to ocean ecosystems, she said.

Adding management measures to 2.6% of the ocean could cover all of the hotspots, according to the study.

Only a small portion of that has management measures that work to reduce the threat to whales. Voluntary programs along the California coastline ask really large vessels to slow down, like a traffic school zone for whales, or to reroute away from areas with a lot of whales. So far, whale researchers say it’s working — and could help in other high-risk areas.

About 10 years ago, Hastings helped start the Protecting Blue Whales and Blue Skies program, which encourages large ships to slow down in areas of known whale activity off the California coast.

The voluntary slow down zone, like a traffic school zone for whales, is about 100 miles long and extends about 50 miles offshore, Hastings said. Slowing from 15 knots to 10 knots adds a few hours to a days-long trip, he said.

“To put that in perspective of the ship’s total transit, when it leaves a port in the Philippines or Asia, it’s a 20 to 28 day trip,” Hastings said. “So we’re talking hundreds of hours and we are adding  three or four hours.”

Those slowdowns last roughly from May to December, he said. But this year, the speed slowdown had to be extended through Jan. 15 because the humpback whales “didn’t get the memo,” he said. “There’s a lot of good food. So the humpbacks are still in the region.”

In addition, slowdowns help ships burn less fuel, which results in less air pollution and greenhouse gas emissions, Nisi said.

The team is also in talks with tribal and wildlife leaders in Washington, Hastings said. They’d like to consider reducing vessel speeds around the Olympic Coast National Marine Sanctuary, which would help as ships head into Puget Sound.

“ The same ships and captains are passing through California waters and are very accustomed to our ship program,” Hastings said. “When they get into Washington waters, you have the same whales, you have southern resident killer whales, and we think the program can expand and help with conservation.”

One of the next steps, said Jono Wilson, with The Nature Conservancy, is to figure out what these slowdowns could mean for the global economy.

“Shipping companies have deadlines to meet,” Wilson said. “They have commitments to their consumers, to their retailers, that they’re shipping these goods. About 90% of all goods that we consume come to us via a shipping vessel on the high seas.”

So far, that compliance hasn’t been too difficult in the Protecting Blue Whales and Blue Skies program, Hastings said. Right now, about 86% of large vessels cooperate with the voluntary measures, he said.

In addition to slowing down, vessels can also reroute when large groups of whales are in certain areas. Researchers are also improving ways to detect whales and how to report strikes.

Nisi said she wants to study how these dynamics shift with climate change. Where whales roam is expected to change, as are shipping routes, especially in the Arctic Ocean, she said. For now, she said she hopes this study helps reduce vessel-whale collisions.

“ We already have these tools that we know are effective,” Nisi said. “But it’s now a question of scaling up these existing effective tools.”