A fisherman who suffered a fatal sea snake bite told crew mates he felt fine hours before his death.

Harry Evans, a 23-year-old British man, was pulling up a net on a fishing trawler hours away from Australia's northern coast when a sea snake bit him on his thumb.

Moments after the bite, he said he felt normal, took a shower and put antiseptic on the bite, his mother Sharon Evans told The Sun.

"Then his eyes rolled and he drifted in and out of consciousness for a while and fell asleep," she told the newspaper.

She learned Thursday he had died from the bite working his dream job.

It was a "tragically unlucky accident," venom expert and professor at University of Queensland told the BBC.

Evans was known as a generous, funny person, according to friends and family.

"He was one of the kindest people you could meet," Evans' twin brother George Evans told News Corp Australia. "Even if he was down to his last £10, he would buy you a drink."

Sea snake bites are extremely rare and extremely venomous. Symptoms, such as in Evans' case, might not be immediate, and the site of the bite might also look somewhat normal without redness or bruising.

Body aches, blurred vision, difficulty breathing and unconsciousness might not occur until two hours after the bite, according to DoveMed.

Evans' death is the first of its kind in Australia in more than 80 years, ABC Australia reports. In 1935, a Japanese pearl diver died after he was bitten in a nearby area.