Another whale that Howlett had rescued last year after it became caught in a fishing net (Picture: IFAW)

A lobster fisherman saved a whale tangled in a fishing net – but it killed him shortly afterwards.

Joe Howlett, from New Brunswick in Canada, had saved around two dozen endangered whales during his last 15 years on the seas.

He had sailed off the province’s eastern coast on Monday to help rescue a north Atlantic right whale that had become tangled in rope.

North Atlantic right whales are already at risk, with a global population of just 525.

Howlett successfully managed to free the whale, but was struck by the mammal just moments later, the local paper Medicine Hat News reported.

Mackie Green, from the Campobello Whale Rescue Team, told the paper: ‘They got the whale totally disentangled, and then some kind of freak thing happened and the whale made a big flip.’

The federal fisheries department confirmed that Howlett had been killed while on one of its boats, adding that he was ‘an irreplacable member of the whale rescue community’.

In a statement, they said: ‘Taking part in whale rescue operations requires immense bravery and a passion for the welfare of marine mammals.

‘There are serious risks involved with any disentanglement attempt. Each situation is unique, and entangled whales can be unpredictable.’