Rescuers hopeful for freed orca's future despite injuries

Rescuers are hopeful for the future of the injured orca whale successfully freed from a crayfish line he was tangled in.

Marine experts had been working since Monday to free the orca from the cray pot line it became caught in near Tutukaka in Northland on Sunday night.

Newshub followed the orca around on Thursday from Westhaven to Island Bay. In that time, it rarely moved at a speed above 4 knots, while the average orca swimming speed is 8 knots - which showed just how badly the injury was impeding it.

On Friday night, the orca was freed near Waiheke Island.

Marine biologist Dr Ingrid Visser says she's optimistic about his future now the line is gone.

"It's cut very deeply into him, it's going to take a long time to heal, but we've got high hopes that it will heal completely," she told Newshub.

"The last we saw of him, he was out in the middle of the Firth of Thames and his family was about 10 kilometres away.

"But they should be able to hear him, he's calling out, and now he's free he can catch up to them."

One of the members of his pod is also a rescued orca that survived after its experience.

"One of the females travelling with him yesterday is a female we disentangled in 2015 and she's still doing really well," Dr Visser says.

She says keeping fishing lines short and weighing down trash makes a big difference to prevent any more orcas being tangled in the future.