In 1608 Henry Hudson was searching in his second attempt for a Northwest passage On June 15, near Norway (at 75° 7' N) he reported in his private log:
This morning, one of our company looking overboard saw a mermaid, and calling up some of the company to see her, one more came up and by that time she was close to the ship's side looking earnestly upon the men. A little after, a sea came up and overturned her. From the navel upward, her back and breasts were like a woman's, her body as big as one of us; her skin very white, with long black hair hanging down her back. When the mermaid finally went down under the waves, her tail was observed, which was like that of a porpoise and speckled like a mackerel.
By the matter-of-fact record, it seems obvious Hudson believed in mermaids.
Henry Hudson is, of course, best known for his discovery of the Hudson Strait and Hudson Bay. In 1611, after being iced in the previous winter, Hudson attempted to press on and find a passage to the Pacific. His crew wanted to go home and mutinied that June. According to the mutineers, they set Hudson, his teenage son John, and six crewmen, either sick or loyal to Hudson, adrift in a small open boat, effectively marooning them. Hudson was never seen again and his fate is not known. It is possible that rather than set him adrift, the crew just killed him.