A young French man has been found dead after jumping off a boat into the water at Hobart‘s waterfront.

The 23-year-old was onboard a scientific vessel docked near Princes Wharf 1 when he jumped into the water sometime around 3.55am on Tuesday.

Authorities were alerted when he could not be found and a police helped conduct a search for the young man by boat.

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About 7am police divers entered the water and 45 minutes later found the man’s body not far away, near Franklin Wharf.

Tasmania Police Inspector John Toohey said the man appeared to jump into the water of his own accord.

The circumstances of his death were not suspicious at this stage, police say.

Police are investigating exactly why the man jumped into the water but it appeared alcohol may have been involved.

The young man was part of a crew who were due to change over and fly to Melbourne on Tuesday.

“They’d finished their leg, the boat travels all around the world and Hobart was one of their final legs,” Toohey said.

“The crew was due to fly out today and a new crew is coming today.”

Police at Princes Wharf 1 on Tuesday. Credit: 7NEWS

The man had been onboard a scientific vessel docked in Hobart. Credit: 7NEWS

It’s unclear how long the boat had been in Hobart.

Toohey said the crew is a very “tight-knit” group and had been working together for some time.

The rest of the members were “very distressed” by what had happened,” he said.

Tasmania Police Inspector John Toohey. Credit: Tasmania Police

Police have notified the French consulate and Interpol is assisting with notification of the man’s next of kin.

“Our condolences go out to the friends, family and crew of that individual,” Toohey said.

“It’s a tragic time and a tragic incident that’s occurred down there.”

Toohey warned people against swimming at nighttime, especially on Hobart’s waterfront.

A report will be prepared for the coroner.