The incident took place around 8:30 a.m., Tuesday, Nov. 3, on Ocean Drive West in the Shippan neighborhood area of Stamford, said Stamford Police Capt. Richard Conklin.
The man, who lives on a sailboat in the harbor uses a canoe to go and forth from the mainland, Conklin said.
Residents spotted the overturned canoe and one swan out to rescue the man.
The rescuer was able to get the man to shore where he performed CPR until a "faint pulse" was found.
Marine and patrol officers responded to the scene and performed additional lifesaving measures.
The man was transported to Stamford Hospital where a faint pulse was found, Conklin said.
He remained in "grave condition" early Tuesday, Conklin added.
This is a developing story. Check back to Daily Voice for updates.
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