In Canada, Thamnophis sauritus (Eastern Ribbon Snake) is found only in southern Ontario and a small area of southwestern Nova Scotia. Although the Nova Scotia population is nationally designated as threatened, its distribution, seasonal activity, movement patterns, and over-wintering sites remain undescribed. We used radio-telemetry, capture-mark recapture, and direct observation to: 1) assess abundance, summer activity, and movement; and 2) to locate and characterize a hibernaculum for Eastern Ribbon Snakes in Kejimkujik National Park, NS. A total of 105 individuals were marked; among these, 13 free-ranging adults were surgically implanted with radio-transmitters and tracked from June until mid-November 2001. From late May to September, snakes were always found within 5 m of water, with summer ranges on land that rarely exceeded 5 × 10 m. From September to mid-October, snakes moved up to 173 m away from the shoreline. Eleven observations of snakes feeding on anurans (Ranidae) and fish (Cyprinidae) were made at temporary pools, marginal to the lake. Despite the use of radio-telemetry, only one hibernaculum was found. Our observations indicate that the Eastern Ribbon Snake is relatively sedentary; its low activity rate and small activity range may make it vulnerable to local extinction.