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  • February 16, 2025
Area off Vancouver Island, a zone with a high risk of ship-whale collisions: study

Area off Vancouver Island, a zone with a high risk of ship-whale collisions: study

In BC, a previously unknown hotspot for whale ship strikes was found off the coast of Vancouver Island.

A new study has identified several previously unknown risk zones for ship-whale collisions, including a large one off the southwest coast of Vancouver Island.

The research, published in the journal Science This week marks the first time anyone has quantified the global risk of whale ship strikes for blue whales, humpback whales and sperm whales.

“This helps us determine where whales are most vulnerable,” said Chloe Robinson, ecologist and director of Ocean Wise’s Whales Initiative and co-author of the study. “There has never been anything this extensive.”

The study found that global shipping lanes overlap 92 percent of the migration routes of four whale species around the world.

Global databases show high risk of deadly ‘odds game’

The research team covered five continents and drew on 435,000 unique whale sightings – from government surveys to sightings by members of the public, animal-worn GPS tags and even whale records dating back to 1960.

They then compared that data to the movements of 176,000 cargo ships between 2017 and 2022. The ships were tracked through their automatic identification system and compared to whaling areas to identify where they were likely to meet.

“We’re talking about five billion ship positions,” said Robinson, noting that a recent study found an estimated 20,000 whales are killed each year by ship strikes. “It’s a bit of a matter of opportunities. The more whales and ships you overlap, the more likely one of those encounters will end in a ship attack.”

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A) Average global distribution for bluefin, fin, humpback and sperm whales; B) Global maritime traffic for large (>300 gross tons) ships between 2017-2022; C) And the global overlap of whaling areas and shipping routes. Anna Nisi

In addition to entanglement in fishing gear, ship strikes are a major threat to large migrating whales.

But lead author Anna Nisi, a postdoctoral researcher at the University of Washington’s Center for Ecosystem Sentinels, said studying ship-whale collisions can be incredibly difficult because a ship will usually strike a whale and it will sink without anyone it notices.

“Sometimes they roll into port with the whale draped over the front of the ship, and that’s when they realize they’ve hit something,” Nisi said.

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In September 2022, a humpback whale named Moon was documented in BC’s northern waters with a serious injury to her spine, likely caused by a collision with a ship. PHOTOGRAPH COURTESY NORTH COAST WATCHWALK FISHING SOCIETY

Ship collision hotspots identified around the world

In the Americas, the areas with the highest risk for whale ship strikes were found along the Pacific coast of North America, as well as off the coasts of Panama, Brazil, Chile, Peru and Ecuador.

Robinson said scientists had a fairly good understanding of where shipping and whale routes overlap in Canadian coastal waters. But as you go further offshore, the risks of collisions between whaling vessels become a lot murkier – yet

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A ferry from BC passes a group of humpback whales. The species has recovered in recent years. Ocean wise

The study found that off the southwestern tip of Vancouver Island, a high concentration of ships transit the same waters that humpback and fin whales use to migrate and feed.

The hotspot for ship-whale collisions is just outside an existing southern orca management zone Swiftsure bank. The area – which includes seasonal speed limits and fish closures – extends about 40 kilometers along the west coast of Vancouver Island, between Port Renfrew and Bamfield.

A little further west, the survey found what Robinson described as a stop on a whale highway, where humpback and fin whales feed and rest before entering the Salish Sea or continuing their migration route north and south.

“It’s a place where strikes are rarely reported,” she said.

Ship strikes are increasing in BC waters

The research comes amid a revival of humpback whale populations and an increase in maritime traffic. According to Robinson, the combination has increased the collision risks.

Between 2022 and 2024, Ocean Wise has tracked at least 15 whale strikes in BC waters. And while another recent attack is still under investigation, Robinson says the actual total is much higher because most collisions go unreported or unnoticed.

“This is something we’re seeing more and more every year,” Robinson said. “Across BC’s coast, at least 10 humpback whales were struck on 10 separate occasions last summer. And this is exactly what we know.”

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A rotting humpback whale on Haida Gwaii on November 20, 2022. Edda Koenig

Humpback whales are born into a life of migration, traveling between northern and southern feeding and breeding grounds each year. The whales tend to sleep on the surface during their migration, putting them at high risk of being struck.

Ships have also increased by 300 percent in the last thirty years, Robinson. “So it’s a real concern for these species.”

The greatest risk of strikes occurs in territorial waters

The research shows that more than 95 percent of hotspots for whale ship strikes are close to shore, where countries can protect marine life within their exclusive economic zones.

Yet only seven percent of the areas most at risk of collisions were found to have measures in place to protect whales.

The study found that installing management regimes on just 2.6 percent of the ocean’s surface would protect whales in all the highest-risk locations.

“It concerns a small percentage, but of course a very large area,” says Nisi. “This means there’s just a lot of need and a lot of opportunity to expand these protections for whales.”

Long-term coexistence requires cooperation with industry, says ecologist

Efforts to slow and redirect ships passing through whaling areas have improved in recent years. In Sri Lankan waters, the Swiss-Italian-owned Mediterranean shipping company voluntarily diverted its ships around a key whaling area, Robinson said.

“Hitting whales is bad, not only for their image, but also for the environment. And they support these measures because they are looking for long-term coexistence,” she said.

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A dead blue whale wrapped on the bow of a container ship in Colombo, Sri Lanka. Sopaka Karunasundara

Closer to home, a system of hydrophones, infrared equipment and human reporting now informs whale warning systems off the coast from Washington to BC and Alaska.

What needs to happen next, Robinson said, is expand that system to previously unknown hotspots further offshore, such as the area west of Swiftsure Bank.

That could mean expanding the Swiftsure Bank management area by just a few kilometers to help humpback and fin whales – two species that cannot echolocate objects like their toothed killer whale relatives.

Infrared cameras can help detect whales

Robinson said she believes one single measure could have a big impact: equipping ships with infrared cameras to detect whales within a few kilometers. “Maybe some sailors… respond better to knowing that there is 100 percent a whale 200 yards in front of your ship, rather than slowing down, maybe there is a whale here.” ”

Robinson said such cameras can cost between $50,000 and $75,000, but they can be an opportunity for companies to promote themselves as operating in a more whale-friendly manner.

“I know people who had to go to therapy after killing a humpback whale while they were at the helm,” she added.

Without protection, Robinson said, Arctic waters could become the next high-risk hotspot as sea ice melts due to climate change, opening up shipping lanes.

“Knowing the plans to extend shipping routes to these areas to reduce shipping time and speed things up, right through prime whale habitat, I think this is a very good opportunity to put the issue forward before it becomes a problem.”

​ — With files from Brenna Owen, Canadian Press