St. Mary Reservoir Fishing in Cardston County, Alberta

• Overview

  Look for St. Mary Reservoir in Cardston County, Alberta. The land about it is lake country bush. Surface area runs to some 29.18 sq km, so a boat and a plan are both worth having. Some 95 km of shoreline means conditions can differ from one end to the other. By surface area it heads our Cardston County listings. The nearest town is Cardston, 17 km away. The big place round here is Lethbridge, 49 km distant. The nearest boundary is well away, so one set of rules covers the water.

• Where to Fish on St. Mary Reservoir

  No depth figure has reached our records, which makes a plummet useful. Standing timber shows when the level drops, and fish sit against it. A reservoir gives you a hard edge, a shelf, and not much else. Open biodiversity records for Cardston County list longnose sucker, white sucker, mountain whitefish, mountain sucker and brown trout. Several of these carry legal protection or closed seasons; the rulebook comes before the rod. Treat St. Mary Reservoir as a water to read rather than to cover.

• Seasonal Patterns

  Expect August near 17°C and January near -7°C on the long-run figures. The freeze arrives properly here and holds. The open season starts with the thaw, near enough early April. Averages place the thaw at early April and the freeze at late November. Reckon on open water from spring through to late autumn, with May and June the strongest. Anyone fishing St. Mary Reservoir regularly works to that calendar.

• Tackle & Baits

  The rules here are undocumented as far as public sources go. Nothing formal is recorded here: no ramp, no car park, no marked path. Trout here take small spinners, spoons and, where fly water allows, a nymph or dry. Ask in the nearest town if you are unsure. Some stretches are reserved and marked as such on the ground. Ross Lake at 28 km is the sensible second choice. Nothing on St. Mary Reservoir should be assumed from this page alone.