Damian Johnson, 46, was unable to be revived after being mauled by the shark, thought to be a great white.

The father-of-two was diving with his daughter early on Saturday morning when the shark attacked him underwater.

The pair were diving in waters about 12 metres deep between Maria and Lachlan islands on the state's East Coast.

Mr Johnson had taken a solo trip underwater to collect a second haul of scallops between 7 and 8am when his daughter became concerned at how long he had been beneath the surface.

The young woman, aged in her 20s, witnessed the attack when she went underwater to check on her father, before swimming back to their boat to set off a flare to raise the alarm.

Mr Johnson's brother-in-law Andrew Paynter told the ABC the family was devastated, describing him as a "great bloke, devoted husband [and a] great father".

Mr Paynter encouraged others not to be put off by the attack, which was the first shark fatality in Tasmania since 1993.

"He certainly wouldn't be put off by it, I'm sure," he said.

"If it was not him, he'd be back in the water at the next available opportunity."

Mr Paynter said family members were struggling to deal with their loss.

"Obviously everyone's still in a substantial amount of shock so [we are] just coming to terms with the reality of it really," Mr Paynter said.

Mr Paynter said Mr Johnson's daughter, who witnessed the attack, was receiving support from the family.

"She's a really tough lady ... she's doing a remarkable job under, as I'm sure you can appreciate, some really really trying circumstances," he said.

"[He was] just a great bloke, devoted husband, great father, just a great friend to all those who knew him."

He said Mr Johnson would never have wanted the shark to be killed.

Glamorgan Spring Bay Mayor Michael Kent said about three boats had gone out searching for the animal on Saturday evening but were deterred by police patrolling the water.

Cr Kent said the community was deeply hurt by the incident and extended his condolences to Mr Johnson's family.

"I was over there today around the wharf area and in the marina area particularly there's absolutely nobody there at all," he said.

"Tasmania is not known for people being killed by sharks.

"It's going to take a few weeks for everything to get back to normal."

Local divers questioned why a warning had not been more prominent following repeated sightings of large great white sharks in the area in the fortnight prior.

A Maria Island senior park ranger noted that reports of shark sightings had gone over marine radio on Friday and Saturday before Mr Johnson's death.

Tasmanian Association for Recreational Fishing chief executive Mark Nikolai said he believed nothing more could have been done to prevent the incident.

He said it was important the community kept the tragedy in context: Mr Johnson's death marked Tasmania's sixth shark fatality in 200 years.

"I'm not sure there's anything additional or that should have happened," Mr Nikolai said.

"It's extremely rare that it happens and I can't see there's been any fault from anybody."

Primary Industries and Water Minister Jeremy Rockcliff would not be drawn on the efficiency of systems in place because of the ongoing police investigation.

"This is devastating news and the Tasmanian government of course offer our deepest sympathies to the family through what is an absolutely heartbreaking, tragic and extremely difficult time for them," he said.

Police patrolled the water around Maria Island until 1pm on Sunday and will continue a coronial inquiry into Mr Johnson's death.

Story courtesy of The Examiner