Islands of Discovery are re-emerging as a BC humpback hotspot

The return of Nick the humpback whale year after year with his brood to the waters surrounding the Discovery Islands, sandwiched between BC’s remote central coast and Vancouver Island, is wonderfully symbolic.

He frequents the waters off Cortes Island near Whaletown — a whaling station and rendering plant once established in 1868 as part of the colonial industry that destroyed humpbacks in the waters east of Vancouver Island in the early 20th century.

Now the species is back. Among them is Nick, named for the distinctive U-shaped notch on the dorsal fin.

Jackie Hildering, a whale researcher and co-founder of the Marine Education Research Society (MERS), said a fertile mother has given birth to five calves since 2008 – the latest this year.

Isolated sightings of humpback whales were again reported in the Strait of Georgia in the mid-1980s, but mass marine mammal sightings in the Discovery Islands area have increased rapidly in the past decade, making it one of the hotspots for whale giants. Salish Sea, Hilding said.

“This area went from 23 individual sightings in 2015 to about 100 humpbacks feeding from the Discovery Islands four years later,” Hildering said.

“It’s a rare piece of good news that we didn’t push the humpbacks out and they were able to repopulate,” he said.

According to Hilding, the increase in the number of humpback whales in Discovery Islands and northeastern Vancouver Island waters is not just due to population growth. But where the new residents came from remains a mystery to whale researchers in the North Pacific.

Climate change is a global threat, and scientists believe that higher water temperatures could potentially alter the whales’ food distribution – possibly resulting in nutritional stress and reduced reproduction, as well as changes in foraging and breeding grounds or migration schedules.

Humpback whales in southeast Alaska have experienced drastic population declines, along with survival and reproductive rates, due to a two-year intense marine heat wave dubbed The Blob that smothered the Pacific coast beginning in 2014.

However, the humpbacks missing from Alaska are not the same whales seen in waters east of Vancouver Island, Hildering said.

If we can take measures to protect the whales, the return of humpbacks to this region gives the residents a chance to survive. Hildering said the biggest immediate and preventable threats are still human-caused in the form of boat strikes and fishing gear entanglement.

Fifty percent of humpbacks in the region have hook marks, he said, adding that the impact of boat strikes is more difficult to determine because whales killed by boats usually sink to the bottom of the ocean.

Humpback hotspots are often areas of heavy boat activity, increasing the risk to whales that return to their favorite nesting grounds each summer to feed. Image courtesy of MERS

Nick is scarred from collisions with gear and ship, but survives to accompany each of his offspring on their first trips to their beloved coastal waters. Calves stay with their mothers for only one year.

One of Nick’s last calves, Splashy, born in Hawaii in 2020, arrived in BC that same summer. In the early winter of 2021, a young humpback made waves with researchers when it was spotted swimming alone in and around Hornby Island. This event raises questions about when and under what conditions young humpbacks leave their mothers and migrate to warmer waters.

Accompanied this summer by his latest calf, Maite, in memory of the young victim of the mass school shooting in May in Uvalde, Texas, Hildering noted that the 11-year-old wants to be a marine biologist. .

Humpbacks in the region simply don’t go anywhere else, Hildering said.

It encourages citizens to report humpbacks in local waters and respect them as individuals and neighbors to help researchers determine the specific areas the animals frequent, their feeding strategies, survival rates and injuries, and how we can better protect them.

The whales come to the Discovery Islands in the summer to harvest krill and small schooling fish in BC’s cool, dark waters – like many Canadian snowbirds – before migrating to spend the winter in Hawaii, Mexico and perhaps Central America or Japan.

Those destinations have warmer waters with less food, but are safer nurseries for newborn calves, he said.

The resident added that whales prefer specific behaviors and fishing techniques adapted to the region.

The area’s waters are characterized by fast currents that tend to scatter fish, so humpbacks don’t often use a popular technique known as “bubble net feeding” – where whales cooperate with one member to keep a school of fish blowing a net. consists of bubbles to prevent their prey from escaping.

The MERS study found that the region’s humpbacks developed trap bait, a sort of lazy-man version of the more commonly used lunge method, in which the animals fill a dense shoal of fish and stuff them into baleen mosquitoes.

This unique technique sees whales lying on the surface of the ocean with their mouths open, seeking shelter inside the large jaws of small fish and fleeing seabirds.

The humpback then spins or uses its fins to push the fish into their baleen mouths to secure their food.

More than 20 area humps rely on this energy-saving technique when the fish aren’t forming dense schools, MERS said.

According to Hildering, the safety of whales and people is improved if recreational boaters and vessel operators are well informed about the habits and favorite spots of local humpbacks.

He said humpbacks don’t use sonar to hunt and don’t pay attention to ships, especially if they’re feeding during the day and can surface unexpectedly.

Slowing down at humpback hotspots and paying attention to other whale indicators — like flocks of birds in the water or the “bump” when sea giants release a cloud of moist air when they surface — help boat operators avoid colliding with a school bus. – sized marine mammals.

Whales have very random travel patterns, so boaters shouldn’t assume the humpbacks will move in the direction they went on their last observed dive, he said.

A whale called the Inukshuk, which has been returning to the area since at least 2008, is known for spending long periods at the surface during the day because it tends to feed on krill at night, Hildering said.

That means it rarely “blows over” and is like a plank that boaters can’t get far enough from, he said.

It is worth taking extra care to protect the inukshuk, as it is loved for being one of the region’s best-known vocalists when it sings during the day.

Although all humps vocalize, only the males sing the complex songs for which the species is known.

However, most males in the region tend to sing at night and are therefore more difficult to recognize.

Canada’s Marine Mammal Regulations state that boaters must stay at least 100 meters from humpbacks and double that distance when they are at rest or accompanied by calves.

But MERS advises boaters to keep 200 meters away from humps.

“We can act on this incredible privilege of returning to our shores and having a second chance with them,” Hildering said.

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