A Summary of Sport Fish Communities in Seven High Mountain Lakes in Southwestern Alberta
The 2004 assessment of sport fish communities in high mountain lakes represented a collaborative effort between Alberta Sustainable Resource Development, Shell Canada Ltd. and the Alberta Conservation Association (ACA). In 2004, the ACA assessed sport fish communities in seven high mountain lakes using test netting and test angling methods. These data were contrasted to previous data on sport fish communities collected between 1968 and 1991. Of the seven lakes assessed, three contained one of three species each i.e., cutthroat trout, rainbow trout, or brook trout and four contained golden trout.
A total of 22 cutthroat trout were netted in Phillipps Lake while angling resulted in a total of 7 trout and a catch-per-unit-effort (CPUE) of 0.93 fish/hour of test angling. Phillipps Lake had the highest angling CPUE of all the high mountain lakes.
A total of 22 rainbow trout were gill-netted over a 16-hour period at Window Mountain Lake, while the CPUE ranged from 0.53 on day one to 0.35 trout/hour on day two. The 1977-1990 voluntary creel average CPUE for Window Mountain Lake was 0.36 trout/hour.
A total of 24 brook trout were captured during 28 hours of gill netting at Grizzly Lake. Grizzly Lake had a CPUE of 0.86 brook trout/hour. The brook trout population in Grizzly Lake proves to be self-sustaining since the lake’s last trout stocking was in 1962.
Lower Southfork Lake produced the most golden trout compared to Upper Southfork and Barnaby lakes with 21 golden trout gill-netted within 3 hours and a CPUE of 0.20 golden trout/hour of test angling. Some habitat alterations may enhance these three fisheries. The Alberta Fish and Wildlife Division have conducted golden trout fry transfers from Rainy Ridge Lake to Southfork lakes and Barnaby Lake over the years. The 2004 aging results show that some natural reproduction may have occurred in Lower Southfork Lake but without these trout transfers the lakes would likely become fishless overtime. The golden trout transfers are conducted approximately every other year and appear to be successful at sustaining trout numbers in the three lakes.
Rainy Ridge Lake had a CPUE of 0.45 golden trout/hour in 2004, the highest CPUE of the four golden trout lakes. The voluntary creel average CPUE at Rainy Ridge Lake during 1981-1990 was much lower at 0.18 fish/hour. Rainy Ridge Lake had the highest gill net captures at 32 golden trout within 8.5 hours and 57 golden trout within 12 hours. The Rainy Ridge Lake population estimate increased since the 1988 estimate of 532 trout to 912 golden trout (>471 and <6804) in 2004.
The trout populations at these seven high mountain lakes appear to be stable with current angling pressures and current stocking or natural reproductive rates. Habitat improvements at the outlets of some of the lakes may encourage self-reproduction and enhance the total fish population within the lakes.