A 52-year-old Nelson man has been charged with the murder of John Murray Morton, whose body was found on a boat earlier this month.
Mr Morton's body was found in Nelson Haven, beside SH6 in Atawhai.
Detective Inspector Paul Borrell of Nelson police said the arrested man had been known to Mr Morton.
Police have confirmed they were not looking for any one else in relation to the death.
Police said an anonymous tip-off had led to the arrest.
A team of detectives from Nelson, Christchurch, Dunedin and Invercargill have been working on the case.
Mr Borrell said he wanted to pass on his thanks and appreciation to members of the Nelson community for their support in the investigation.