Friends and associates confirmed a body found in the water at Watsons Bay, in Sydney’s east, on Thursday morning was that of the 59-year-old.
“He leaves behind a huge vacuum for Indigenous art in this country and around the world,” Mr. Davidson said on Friday.
Sydney gallerist Michael Reid said the art community has received the news with “profound sadness.”
The then-head of Sotheby’s Aboriginal art section was approached by the couple in 2005 to sell a painting of a rainbow serpent they claimed was by renowned artist, Rover Thomas.
Friends said the art dealer had gone out on a boat for a fishing expedition early on Thursday.
NSW Police Marine Area Command initially responded to reports of boating debris floating in the water off Watsons Bay.
Officers recovered the body of a man in the water of the debris field, police said in a statement on Friday.
Police have been searching for another man also thought to be onboard, who remains unaccounted for but is presumed dead.
The large search for the second man was significantly scaled down from Sunday.
Efforts to locate the missing man had been extensive.
“We threw the police divers at it and they searched 1000 metres of shoreline and underwater areas looking for the second person,” Marine Area Command Superintendent Joe McNulty said.
He founded Sotheby’s Aboriginal art department in 1996, touring works internationally before their sale in Australia.