Erik The Red has been the rodent control officer aboard the ship for more than 15 years.
He took up the role in 1999, when the malnourished stray kitten followed Acadia shipkeeper Stephen Read back to the vessel.
The pair would spend the next decade and a half living together on the ship, with Erik sometimes leaving rodent surprises in Read's shoes.
The friendly feline has become a fixture on the Halifax waterfront, often dropping into gift shops and napping on the boardwalk.
Erik, who is believed to be between 17 and 20 years old, has been semi-retired for a few years and now lives at a home in Halifax's north end.
The Acadia, a Canadian Scientific Ship, was retired in 1969 after 56 years of service and is now a permanent floating museum on the Halifax harbour.
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