Tilikum, the orca whale that killed a trainer and was the subject of controversial documentary Blackfish, has died at the estimated age of 36.

Seaworld announced the whale's death on their website in a statement which said Tilikum "faced some very serious health issues" and that he suffered from a "complicated bacterial lung infection".

He had been ill since March last year.

President and CEO of Seaworld, Joel Manby, said: "Tilikum had, and will continue to have, a special place in the hearts of the SeaWorld family, as well as the millions of people all over the world that he inspired.

"My heart goes out to our team who cared for him like family."

The male orca whale was implicated in the deaths of three trainers over his years at Seaworld. In 2010, Dawn Brancheau was dragged into the water by her ponytail and drowned.

After her death, the tragic incident was the subject of a controversial documentary, Blackfish, which sought to look at the behaviour of killer whales in captivity.

Seaworld Entertainment said at the time of the film's release that it was "inaccurate and misleading and, regrettably, exploits a tragedy".

A trainer works with Tilikum, a year after the tragic accident in 2010. Credit: AP