There are three subspecies of lake trout. There is the common Lake Trout (Salvelinus Namaycush Namaycush), the Siscowet Lake Trout (Salvelinus Namaycush Siscowet) and the less common Rush Lake Trout (Salvelinus Namaycush Huronicus). Some lakes do not have pelagic forage fish during the period of summer stratification. In these lakes, lake trout take on a life history known as planktivory. Lake trout in planktivorous populations are highly abundant, grow very slowly and mature at relatively small sizes. In those lakes that do contain deep-water forage base, lake trout become piscivorous. Piscivorous lake trout grow much more quickly, mature at a larger size and are less abundant. Common lake trout tend to stay in shallower waters, while Siscowet lake trout stay in deeper water.    

Rock lake is a small, deep scenic lake situated in the front ranges of the Rocky Mountains in Alberta. It is located in Improvement District No. 14, 75 km northwest of the town of Hinton, 4 km north of Jasper National Park and 1 km east of Willmore Wilderness Park. Three permanent streams enter the lake. Rock Creek, which flows into the western side, and it provides the majority of the flow (Lane 1969). The outlet is a fork of the Wildhay River, which eventually drains into the Athabasca River. The Athabasca river is a of the Mackenzie River which eventually flows into the Arctic Ocean. Rock Lake is a small waterbody that is relatively deep for its size. The lakes maximum depth of 27.8 m (91.2 ft) is located in the centre of the single basin. The Bottom substrate in most areas, to a depth of approximately 10 m (32.8 ft) is rich in organic matter, with numerous sand and gravel bars. There are four types of fish for anglers to pursue in Rock Lake Bull Trout, Mountain Whitefish, Pike and Lake Trout.  

Swan lake is west of Caroline and is 2.1 kilometres long and 700 meters wide at its widest point. While not large, the lake can give up large trout in the range of four to six pounds. The most accurate data we can get is that Swan Lake is just over 40-43 feet deep at the deepest. The Alberta record Brown Trout was set here in the early 1990’s and Swan Lake also contains a few large pike. Swan lake is a natural lake with a weir at the far end on the downstream exit of Swan Creek from the Lake. The lake is south of Rocky Mountain House, and is accessible via. Hwy 22.  Drive 35 Km to the junction with secondary Hwy. 591 on the right. Follow this for 20 Km to a side road on the right (north) and continue along this road for another 20 Km until reaching Swan lake. There are 24 camp sites with picnic tables and fire pits. Facilities include dry toilets, boat launch, dock, refuse containers, fish cleaning stations, fire wood and a community cook shelter.

Lake Trout have a long-life span and can live to 20 – 25 years of age, they can attain 10 kilograms (22 pounds) in weight. They have a very drab plane appearance with very little colour overall most times. They are generally a grayish tone with asymmetrical white spots. During the fall spawning season, their fins located near the caudal (tail) fin turn a vivid or pale orange. The tail or caudal fin has a very defined fork in it. Lake Trout are native to many deep cold lakes in Alberta. Lake trout come in shallow to feed near the surface of a lake when the water is cold which mostly occurs in the spring and again in the fall. During the summer, the cold denser water sinks to the bottom of the lake and the trout most assuredly follow that trend down into the deeper cooler water. Young lake trout feed on freshwater shrimp and other aquatic invertebrates.

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Larger lake trout eat other species of fish, mostly whitefish and cisco (tullibee) when and if available. The lake trout in swan lake demonstrate a full-on feeding pattern involving Mayfly nymphs, jumbo chironomid larva and fresh water shrimp at one time or another throughout the season when available. Lake trout grow very slowly, and often don’t mature until they are 8-10, years of age. On Swan Lake it may even take longer than that due to how shallow and relatively warm the water temperatures are due to this fact compared to lakes in the Rockies that are at least 90 -150 feet deep and much colder. Due to both the lack of any real forage base and the overall shallow nature of the lake the lake trout present in the lake do not age or grow in the same manner as they would in more natural habitat. Lake Trout only do well in lakes where the water temperature does not exceed 18° C (65° F). The temperature for maximum activity is from 15° C (59° F) – 17° C (62.6° F). The ultimate upper lethal temperature is estimated to be 23.5° C (74.3° F).      

THE University of Alberta (U OF A)

 Fishes of Abraham lake (reservoir) and the upper North Saskatchewan River, Alberta

By: Charles Dennis Tebby

Dated: Thesis submitted to Department of Zoology Edmonton, Alberta Fall, 1974  

The Lake Trout, (Salvelinus Namaycush) (Walbaum) this species is considered native to the North Saskatchewan system with relict populations in the head waters area and Swan Lake (Paterson, 1968). J.C. Ward (pers. Com.) reports the species from Glacier Lake and the Alexander River. It is also reported (several sources) from parts of the North Saskatchewan below its junction with the Alexander. J. Rimmer (pers. Comm.) reports the species from Outram Lake (Howse system) and has photographs of angled specimens. Anglers reported to the writer (Charles Dennis Tebby) that in past years they had caught “Lake Trout” at the junction of the Cline River with the North Saskatchewan River. Until specimens are available the report is a hypothetical record. There are no records of any stockings within the study area. The precise downstream movement limits of the species have not been determined and it is possible that Lake Trout will colonize the reservoir (Abraham Lake). 

The Fishes of the Central Canadian Rockies Ecosystem

By: David w. Mayhood

FWR Freshwater Research Limited

Technical Report No. 1995/04-1 (Originally Report No. 9504081

Dated: April 1995

In a paper written by: David W. Mayhood – titled “The Fishes of the Central Canadian Rockies Ecosystem” dated 1995 on pages 31-32 there is some very interesting facts about Lake Trout in this region of Alberta. Lake Trout are believed to be native to a relatively small number of lakes and associated rivers on the east slopes of Alberta within the Central Canadian Rockies Ecosystem (CCRE). 

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In the North Saskatchewan watershed (Glacier, Outram, Clearwater, Swan lakes, North Saskatchewan and Alexandra rivers) and the Bow watershed (Minnewanka Lake) drainages (Ward 1974, Nelson and Paetz 1992, Donald and Alger 1993). The species (Lake Trout) has been introduced into Bow and Hector Lakes, and Spray Reservoir, all in the Bow River drainage; and into the Kicking Horse River drainage in Wapta and Sherbrooke Lakes (Donald and Alger 1993). Non-Native Lake Trout stocks have been introduced into waters with native Lake Trout stocks in Lake Minnewanka (BNP stocking records) and possibly in Swan Lake (Steve Herman, Alberta Fish and Wildlife, personal communication). It is presently not known whether introduced and native Lake Trout stocks have introgressed where they have come in contact, although the potential clearly exists for it.Native Bull Trout have beendisplaced by Lake Trout introduced into Bow and Hector Lakes, although native stocks of each species continue to coexist in two relatively pristine (CCRE) lakes (Glacier and Clearwater, Donald and Alger 1993).   

Lake Minnewanka in Banff National has been stocked with fish from 1901-1972 with a variety of fish species by park staff. It is estimated that 17 million eggs and fry from Lake Trout, Atlantic Salmon, Cisco, Brook Trout, Cutthroat Trout, Splake, Small Mouth Bass, Lake Whitefish and Rainbow Trout were introduced into Lake Minnewanka’s waters. 

Lakes generally associated with either native or enhanced lake Trout fisheries in Alberta range from Spray Lakes, Glacier Lake, Pinto Lake, Outram Lake, Clearwater Lake, Abraham Lake, Rock Lake, Ghost Reservoir, Waterton Lakes, Lake Minnewanka, Cold Lake, Lesser Slave Lake, Touchwood Lake and Swan Lake. Lesser Slave and Touchwood Lakes tend to lean toward the fact that Lake Trout that originally inhabited these two lakes are now lost populations.   

Alpine Lake Trout Fish Sustainability index  – Lake Trout Mountain FSI/ Alberta.ca

1. Swan Lake – Current Adult Density: Low
2. Swan Lake – Historic Adult Density: Moderate
3. Swan Lake – Habitat Protection Need: High
4. Swan Lake – Over Harvest Protection Need: Very High

Fish species stocked into Swan Lake

In 1950 there was 110 Brook Trout stocked into Swan Lake unknown size.

In 1953 there was 16800 fingerling Rainbow Trout stocked into Swan lake.

In 1975 there was 8163 Lake Trout stocked into Swan Lake believed to come from Lake Minnewanka. 

In 1976 there was 5324 Lake Trout stocked into Swan lake believed to come from Lake Minnewanka.  

There may have been other stockings into Swan Lake but these are the only records we can obtain at this time.

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Construction of dams and reservoirs downstream of existing lake trout populations in the National Parks (primarily Glacier Lake, Minnewanka Lake, and Waterton Lake) allowed emigrant lake trout to form new populations. These new populations are at low to moderate densities. Of the two original provincially-managed lake trout lakes, Rock Lake fish remain abundant, but fish in Swan Lake have declined to a low density.

Threats to Sustainability

The main threats to Lake trout sustainability in both the mountains and especially the foothills appear to be:

1. Reservoirs are managed primarily for water storage, and consequently lake trout habitat is very limited (example: winter draw-down exposes spawning shoals). Populations likely cannot increase unless water management priorities change.

2. Both native lake trout lakes are small, relatively shallow, accessible, and easily overfished. Strict regulations on harvest will remain necessary.

3. Increasing summer temperatures will continue to limit lake trout habitat within both natural lakes, especially during extreme warming events (example: summer heat periods, drought periods) may result in summer kill.

Next Steps       

1. If lake trout are deemed a priority to manage in the reservoirs, water use plans must be adjusted to allow for consistent spawning and recruitment.
2. Cooperation with the management and conservation of lake trout in the upstream National Parks is critical, as these populations are likely the source of replenishment for Alberta’s fish. These populations (and those in Jasper) may also provide genetically-similar lake trout should extreme climate events cause the two lake populations to be lost.