Hi Keith, the trout that you catch at St Mary's Lake are stocked trout. They come from the Vancouver Island Trout Hatchery, which is operated by the Freshwater Fisheries Society of BC. Both rainbow trout and cutthroat trout are stocked. Unlike other put and take lakes on Vancouver Island, where fish at catchable size (12 to 14 inches long) are stocked, fish put in St Mary's Lake are yearlings (30 to 100 grams heavy). They are planted as yearlings so they are faster and bigger than fry, to avoid predation, yet will grow to become large trout at a natural growth rate due to the environment. It takes a couple of years before they become the large ones that you have encountered in the past. These fish are sterile/triploids so the objective of these plantings is to create angling opportunities. In 2007, 3,000 rainbow trout yearlings and 4,000 cutthroat trout yearlings were planted.