RCMP Sgt. MJ Deluco said the 10-metre boat was first spotted from the shore Thursday evening. Police were called Friday when locals noticed it was taking on water.
Deluco said a civilian took a boat out to inspect the vessel and there was no sign of anyone on board.
The vessel sank before the coast guard arrived.
"We're hoping of course to learn the name of the boat, the registration of the boat and from there we'll determine ownership of the boat. The dive team is in the water now, they're going to examine the boat as closely as they can and they'll be bringing back some photographic information," Deluco said.
She said a ground search team combed the shore Saturday.
So far no one has claimed ownership of the sailboat.