The story
The etymology of the name of the town on Prince Edward Island is uncertain. According to one theory, the toponym derives from a calque of French souris (“mouse”), referring to an infestation of mice near the site of the current town. According to an opposing theory, the toponym derives from a corruption of French Havre à l'Échouerie, derived in turn from havre (“harbour”) and échouerie (“bar”), referring to the mouth of the Souris River.
Etymology from Wiktionary, CC BY-SA 4.0.