Rescuers partially free 1 of 3 entangled right whales in Gulf of St. Lawrence

A rescue team in New Brunswick partially freed one of three entangled North Atlantic right whales in the Gulf of St. Lawrence Thursday.

Right whale No. 4423, a five-year-old male, was spotted around 10 a.m. local time on Thursday during an aerial surveillance flight by the U.S. National Oceanic and Atmospheric Administration (NOAA).

The Campobello Whale Rescue team removed fishing gear that kept the whale from using its tail when diving.

"Attempts to remove additional gear had to be interrupted at dusk," DFO said in a statement.

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However, more rope remains around the whale's mouth, forming a kind of bridle underneath its belly, according to Amy Knowlton, a senior scientist at the New England Aquarium.

"They cut the rope that was going to depths below the bridle, that's what we believe they were able to accomplish," she said. "But there's still that bridle of rope attached through the mouth."

It will take some weeks for rescuers torelocate the whale and see what's happening with the gear that remains on it, she said.

The rescue mission

When the whale was spotted, the team standing by on the Shippagan shores, near Miscou Island, N.B., got on the water.

Once they were close enough, they worked on disentangling it until sunset, Knowltonsaid.

She's been in Shippagan with other researchers studying the whales' food, population and physical well being since July 5.

On Thursday, the boat she was on, the Jean-Denis Martin, was on standby next to the rescue vessel in case of emergency for several hours.

"We sort of tag teamed with a DFO vessel to do that," she said.

The almost 13-hour rescue effort was not easy, she said.

Once they got close to No. 4423, the rescue team had two goals. The first was to attach what they call a "control line" to the trailing gear surrounding the whale, so that they can better assess the entanglement and locate the whale more easily.

But the rescue team was not able to get the control line attached on Thursday.

"The whale became evasive after a few approaches," she said.

So they moved to using a tool called a cutting grapple. Knowlton said the grapple has knives on the inside of it so when it's attached to a rope, it can cut throughif enough tension is applied.

They were able to attach the grapple to the rope that was around to the whale's tail, and trailing something heavy.

"They felt tension and then they felt it pop," she said. "They believe that the rope parted from the heavy weight. That's our hope anyway."

The team was not able to reach the rest of the rope wrapped around the whale's mouth.

"If the heavy weight has been removed there is a chance that gear may shed ... we'll be evaluating that over these next few weeks," she said.

Any rope left on the animal any line left on the animal could be enough to take very seriously injured and jeopardize its survival.- Sean Brillant, Canadian Wildlife Federation

This particular whale posed a lot of challenges to the rescue team, she said. The entangled rope was not trailing behind it, so it was difficult to find the right spot to attach the grapple and trailing line. The whale was also diving deep for periods of time, so it was hard to track.

Knowlton said nonetheless, the team should be commended. "They did a great job in terms of what they were able to accomplish."

Entangled in U.S. waters

During Thursday's rescue, the whale team also received air support from NOAA and DFO's Conservation and Protection airplanes and on-water support from fishery officers.

The whale was spotted entangled on July 4, east of Miscou Island, N.B. But officials believe the animal was stuck prior to entering Canadian waters.

Initial reports indicate it could be a whale first sighted entangled in April 2019in U.S. waters, DFO said.

More entanglements

Surveillance flights continued searching for the two other entangled right whales that were recently seen in the Gulf of St. Lawrence.

No. 4440 has been spotted several times since it was first sighted entangled on June 29, but a disentanglement operation has not been possible.

The third entangled whale was first seen on July 4, 2019 by a Transport Canada surveillance flight east of the Gasp Peninsula in Quebec. This individual whale has not yet been identified, DFO said.

Sean Brillant, senior conservation biologist with the Canadian Wildlife Federation, said even a partial disentanglement is a huge accomplishment

But the goal is to remove all the rope from around the animal's body.

"Any rope left on the animal, any line left on the animal could be enough to ... jeopardize its survival," he said.

"And this is all very difficult as they say because the animalis mobile. It's probably in a lot of pain and discomfort or confusion. It doesn't like being close to boats."

DFO said search operations will continue depending on the weather conditions.

On Monday, Transport Canada announced additional measures to protect the endangered whales.

The measures include further reducing ship speeds in the area, increasing zones in which the speed restrictions will apply, increasing aerial surveillance, and funding for initiatives to enhance marine mammal response.