QUIRK CREEK BROOK TROUT SUPPRESSION PROJECT
 THE QUIRK CREEK BROOK TROUT SUPPRESSION PROJECT is a collaborative effort involving the Fish & Wildlife Division of Alberta Sustainable Resource Development and Trout Unlimited Canada. Former TUC staff, Dean Baayens and Greg Eisler, spent considerable time administering the fish identification test to volunteer anglers, coordinating and supervising outings, sampling harvested brook trout, and collecting and entering creel data. First proposed in 1998 and now in its tenth year, this project would not have been possible without the participation of many volunteer anglers over the years, and in particular those dedicated anglers who have harvested most of the brook trout in recent years on unsupervised outings. Funds from Anadarko Canada Corporation, the Alberta Conservation Association and the Parks Venture Fund supported this project.
Brook trout are not native to Alberta, but are present in many montane and foothills waters as a result of extensive stocking. In southern Alberta, brook trout populations have generally increased while native westslope cutthroat trout and bull trout populations have declined. Brook trout life history attributes (early spawning age, reduced longevity and low catchability) have resulted in the near-total replacement of native bull trout and cutthroat trout with these smaller, less-catchable, non-native brook trout.
 Brook trout colonized Alberta’s Quirk Creek subsequent to their introduction to the Elbow River watershed in 1940. Native cutthroat trout and bull trout were the only fish captured in Quirk Creek in 1948, but brook trout had colonized the lower 3 km of the creek by 1978, then spread throughout the entire creek by 1995. Electrofishing surveys in 1995 and 1996 showed that brook trout comprised more than 90% of the total fish population, despite the implementation of reduced bag limits and minimum size limits designed to provide more protection for remaining native trout.
Since 1998, harvest of all fish has been prohibited in Quirk Creek, except by anglers participating in the brook trout suppression project. Management programs to reduce or eliminate non-native trout populations often involve piscicides and/or electrofishing. However, in 1986 a published study (Larson et al.) suggested that experimental angling programs might offer a cost effective, alternative method for reducing densities of non-native trout. Although this study only ran nine weeks, it appeared that anglers reduced the non-native trout population by about 10%.
PROJECT OBJECTIVES:
Since piscicides are only suitable in certain situations and there are insufficient resources to attempt removal of non-native trout by electrofishing in all streams where native trout populations appear to be threatened, the option of selectively removing non-native trout by angling provides an appealing alternative. TUC’s objective with this project was to determine whether angling could be an effective method for reducing densities of non-native brook trout in Quirk Creek, to facilitate recovery of the native trout population.
PROJECT RESULTS:
Angling, in particular unsupervised outings, appears to be sufficient on the lower reach to keep the number of large brook trout at a relatively low level. Based on the fishing pressure and harvest in 2006, it appears that about 100 angler hours per hectare may be sufficient to keep the brook trout population from rebounding to previous high levels, whereas it took about 200 to 300 angler hours per hectare at the start of the study to reduce the population, when the number of large (>150 mm) brook trout was about four to six times higher. The data from this project also suggest that it is necessary to harvest at least 50% of the large (>150 mm) brook trout population to have an effect on that population.
For the more remote upper reach, however, we have been unsuccessful in getting anglers (especially on unsupervised outings) to exert sufficient pressure and to harvest enough brook trout, to substantially reduce the population and maintain it at levels comparable to the lower reach. For this reason, brook trout removal using one-pass electrofishing was started in the upper reach in 2004.
The approach used in the suppression project has the potential to work, provided that the streams selected are readily accessible by anglers (relatively close to a road) and sufficient angling pressure can be exerted over multiple years.
To download or view a PDF of the latest report on the Quirk Creek Brook Trout Suppression Project, click here.
For information on how you can take part in this project, contact Brian Meagher.
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