His family are being supported by police, Victim Support and close friends and family.
"A post-mortem has been completed and police are not treating his death as suspicious," Ms Reeves said.
A spokesperson from Mr Guerin's family said: "We are still in shock. It doesn't seem real and we are still getting to grips with the news that Graeme has gone.
"He was an active man and enjoyed visiting the New Brighton beach area.
"We would like to thank the members of the public who found him and police for their support and compassion."
Anyone who saw Mr Guerin on Sunday is asked to contact police on 03 363 7400 or anonymously through Crimestoppers on 0800 555 111.