Damian Johnson, 46, was killed by "a very large shark" - believed to be a great white - witnessed by his daughter off Maria Island.

The pair were diving in water about 12 metres deep in the Mercury Passage, between Maria and Lachlan islands, on the state's East Coast when the fatal attack took place.

Mr Johnson failed to surface from a solo dive to collect a second haul of scallops between 7am and 8am.

His daughter, Olivia, dived in to find her father and witnessed the ordeal.

The incident was the first fatal shark attack in Tasmanian waters in 22 years and is believed to be only the sixth in Tasmania's history.

Reports of a large shark in the area on Friday night have since raised eyebrows, but no precautions were taken before Mr Johnson's death.

Tasmanian Abalone Council chief executive Dean Lisson said future incidents could be avoided if a stronger alert system was in place for recreational divers.

"[The attack] raises the possibility of establishing some sort of hotline or website where sightings of great whites can be reported," he said.

"Divers could check that website and get some sort of public notification process to advise people of the risk in diving that area."

Mr Lisson said the council recently implemented a text system to alert professional abalone divers to shark sightings.

Tasmania has six abalone diving zones and the abalone season runs from January 1 to December 31 each year.

On Monday, Premier Will Hodgman said the government was seeking answers.

"We will take advice from the relevant departmental agencies and indeed be informed by the findings of the coroner's inquiry," he said.

"We want to allow that to take place as well to best inform us to any improvement that might be made in the future."