The U.S. is suspending whale rescue efforts after a Canadian fisherman died last week during one such mission. 

Joe Howlett, founder of the Campobello Whale Rescue Team, was killed Monday while helping to free a North Atlantic right whale off the coast of New Brunswick. Mackie Green, captain of the rescue group, told the Canadian Press the team had actually succeeded in freeing the animal when “some kind of freak thing happened and the whale made a big flip,” striking Howlett.

The National Oceanic and Atmospheric Administration (NOAA) is now “suspending all large whale entanglement response activities nationally until further notice, in order to review our own emergency response protocols in light of this event,” Kate Brogan, spokeswoman for the NOAA fisheries division, said in a statement.

NOAA will continue to respond to all other reports of stranded marine mammals, she said.

Read more:

Whale rescues can be risky. Jerry Conway, an adviser with the Campobello Whale Rescue Team, told Canadian Broadcasting Corp. News that rescuers are faced with all kinds of dangers, such as getting entangled in the rope themselves, getting dragged over the side of the boat or being tipped into the water.   

However, deaths are uncommon. Howlett was the first person killed by a whale during a disentanglement since the 1970s, when U.S. and Canadian government groups and non-profits began to respond to such cases, said Cathrine Macort, a spokesperson for the Massachusetts-based Center for Coastal Studies, in an interview with the Bangor Daily News.

It is unknown when the suspension will end. 

North Atlantic right whales, which dwell almost exclusively along the east coasts of the United States and Canada, are one of the world’s most endangered whale species, according to the Marine Mammal Commission. Prized by commercial whalers and hunted to the brink of extinction by the early 1900s, there are only 500 left in the world, according to Fisheries and Oceans Canada. Today, they are usually injured or killed when they get struck by vessels or become entangled in fishing nets.

Seven North Atlantic right whales have been found dead in the Gulf of St. Lawrence so far this summer.

“This situation is very concerning,” Fisheries and Oceans Canada said in a statement on June 24, after the fifth whale carcass sighting. “The cause of death is unknown at this time and DFO is committed to finding out what happened to these animals and to protecting this species.”

Howlett, a 59-year-old lobster fisherman, was someone who loved whales and worked tirelessly to save them, members of the marine community said. 

“Joe’s dedication to saving entangled whales was as deep as his love of fishing,” Scott Kraus, head of the New England Aquarium’s right whale research program, told the Associated Press.

Green echoed Kraus, telling the Canadian Press that working to untangle whales was something Howlett loved to do. 

“Joe definitely would not want us to stop because of this,” he said.