The man, named by local authorities as Peter Smith, 64, from Berkhamsted, Hertfordshire, was savaged 10 metres off the shore near the Starfish Hotel in Courland Bay, on the north coast of Tobago on Friday morning.
He sustained injuries to his left hand, left thigh and stomach following the attack involving a bull shark estimated to be eight to 10 feet long and two feet wide, the Tobago House of Assembly said.
Chief secretary Farley Augustine told the PA news agency that Mr Smith was in a “critical, but stable” condition at Scarborough General Hospital on Saturday after surgery had taken place.
He said the man had been holidaying on the island with his wife and friends and had been due to fly home that day.
Mr Augustine added that the local government was working closely with the British High Commission.
The Foreign Office said it was supporting the family.
Several beaches and coastal areas were closed and a 10,000 US dollar bounty previously offered to anyone who could capture the shark was later retracted.
Last year, there were 69 unprovoked attacks and 22 provoked bites worldwide, along with 14 fatalities, according to the Florida-based International Shark Attack File.
