Saturday, October 23, 2021

With more humpback whales in B.C. waters, entanglements are on the rise, too

Roshini Nair 
CBC
© Submitted by Sydney Dixon A mother humpback whale — dubbed Pinky — is a common visitor to Barkley Sound near Ucluelet, B.C., between April and late October.

It takes a village to disentangle a humpback whale — or, in the case of a mother and her calf off the coast of Vancouver Island last week, a community of whale watchers, researchers, Mounties, Parks Canada staff and a team of highly skilled professionals from Fisheries and Oceans Canada (DFO).

These operations are becoming much more common in B.C. waters as the numbers of humpbacks — and people on the water spotting whales in distress — increase.

"There are so many eyes and ears out there," said Paul Cottrell with marine mammal rescue at DFO and a global expert on whale disentanglement.


The whale and her calf were first spotted entangled in fishing gear on Oct. 7 near Barkley Sound off Ucluelet by Sydney Dixon, research director for the Tofino-based Strawberry Isle Marine Research Society.

"This is a female humpback whale that is really well known and beloved in Barkley Sound," said Dixon, who is also a Zodiac skipper for Jamie's Whaling Station, a tour operator on the west coast of the Island.

The whale, known as Pinky to locals, has migrated to the waters off Barkley Sound fairly consistently since the early 2000s, says Dixon.

"She's brought several babies back to our area to our area as well," she said.

Dixon said she was conducting a whale-watching tour when she noticed floats from what appeared to be a crab or prawn trap following behind the pair.

"I realized that either she or her calf were entangled in some fishing gear," she said.
An increasing problem

Entanglements have become more common over the past decade, says Cottrell.

"In the last five years, we've seen an uptick from three to 10 confirmed entanglements to ...10 to 25 animals a year entangled," he said.

Part of the reason, he says, is because there are a lot more humpback whales in inshore waters. For example, the humpback whale population off northeastern Vancouver Island reached 86 in 2018, up from just seven in 2004.

"Getting these animals back is a great news story, but there are more entanglements because we do have [fishing] gear in the water," he said.

The effects of entanglement on whales depends on how much and what type of gear is involved, and where on the body it is.

Some whales might carry gear for years, migrating across the ocean without great effect. But if it interferes with their feeding or if it digs into a whale's skin and causes infection, entanglement can be fatal.

The type of gear found on Pinky and her calf, Cottrell said, was a polysteel rope — a particularly abrasive type that can cut into the skin and tighten up and cause significant harm.

Cottrell said there is significant work going on to reduce entanglements through gear modifications, ropeless technology and ridding the ocean of abandoned gear.

"It will never stop all of them," he said. "Any vertical or horizontal rope line in the water is a potential entanglement. We've had anchor lines, gillnets, all sorts of fishing gear rope … it really is a lot of different things these animals get caught up in."
Highly skilled, dangerous work

Cottrell is a part of a small group of professionals who are specially trained in whale disentanglement. Cottrell is part of the International Whaling Commission's Global Whale Entanglement Response Network that is working to create training and best practices for whale disentanglement.

"There are not a lot of us around the world that do this. There's probably under 25 folks," he said.

 Submitted by Paul Cottrell The Fisheries and Oceans Canada team pose with the gear they were able to remove from the mother and calf humpback pair on Oct. 13.

The work is highly skilled and dangerous. Cottrell's team deals with some of the largest animals on the planet — many of whom are extremely agitated and distressed by their circumstances. In 2017, a volunteer whale rescuer died in New Brunswick after being struck by the right whale he was disentangling.

"[In my experience], these animals are not aware at all that we're helping. They're trying to get away from us, they're agitated, they definitely do not assist us at all," said Cottrell, who has done this work for the past 15 years.

A mother and a calf present an additional challenge.

"You never know how the mom is going to react when you're working with the calf," he said. "We've had animals where the moms act aggressive and other moms that don't but are usually right there touching the calf while we're rescuing the calf and cutting the gear off."

Gear free and bound for Hawaii


In the case of Pinky and her calf, it wasn't even clear which one had been entangled.

Dixon alerted Fisheries and Oceans authorities through the mammal marine hotline and kept in sight of the pair until help arrived.

But — as whales are wont to do — the pair submerged into the ocean's depths and left her would-be rescuers scrambling to find them.

"It's really important to keep eyes on an entangled whale if you are able to, so that you don't lose them. Because if you do lose them, the chances of them being refound and disentangled goes down dramatically," Dixon said.

It took days of searching by RCMP, researchers, fisheries officers and whale-watching teams before the pair was spotted again and tagged with a satellite tracker. Then, a rescue attempt was made.

On Oct. 13, Cottrell's team were able to free the whales by attaching a drag on the trailing gear which started to pull it loose as the animals travelled.

The mother and calf will now migrate to their wintering grounds in Hawaii.

"The good news is they're gear free and the injuries they have look minor overall in terms of what the damage could have been," he said.

This disentanglement was the 15th occurrence this year, Cottrell says, and one of three that were reported last week along Vancouver Island.

While the work of disentangling itself is specialized, Cottrell's team has been training different groups on how to attach a satellite tracker to whales to save time and allow a specialized team to follow up.

It's part of the collaborative efforts to protect these giant mammals, which can live up to 80 years.

"I feel so lucky to do what I do," Cottrell said. "It really takes a team to do that."

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