Lac La Biche Fisheries Restoration Program Summary Report, 2005 to 2013
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Lac La Biche Fisheries Restoration Program Summary Report, 2005 to 2013 2014 ESRD/Lac La Biche Fisheries Restoration Program Summary Report, 2005 to 2013 Lac La Biche Fisheries Restoration Program Summary Report 2005 to 2013 Andrea McGregor Project Biologist Fisheries Management Branch Waterways-Lac La Biche Area 2014 Lac La Biche Fisheries Restoration Program Summary Report Page i 2005 to 2013 © 2014 Government of Alberta ESRD/Lac La Biche Fisheries Restoration Program Summary Report, 2005 to 2013 Executive Summary The Lac La Biche Fisheries Restoration Program was initiated in 2005 as a six-part program with management actions targeting commercial and recreational fishery reductions, walleye stocking, Double-crested Cormorant control, protection of critical fish areas, and monitoring. The social objective of the program was to “improve fishing opportunities for future generations” by restoring the lake to historical conditions. The ecological objectives were to recover the walleye population and improve the overall size structure of the fish community. In 2005, cormorant culling was introduced to complement egg oiling in order to achieve a reduction in the number of birds breeding in the Lac La Biche area. Restrictions on commercial and recreational harvest were introduced in 2006, and more than 200 million walleye fry, along with fingerlings and adult walleye, were stocked between 2006 and 2011. Fall walleye index netting surveys and annual monitoring of cormorants and co-nesting species were conducted in order to assess the ecological responses to management actions. Walleye stocking was successful, increasing the catch-per-unit-effort (CPUE) of catchable sized walleye (>350 mm TL) in a 10-panel net from 0.09 fish·100m-2·24h-1 in 2005 to 14.27 fish·100m-2·24h-1 in 2013. The CPUE for all walleye peaked at 18.35 fish·100m-2·24h-1 in 2011, declining in 2012 and 2013 when annual walleye stocking was stopped. Generally, abundance increased for predator and omnivore fish species, and decreased for prey groups. Changes in the population size structure for yellow perch and lake whitefish suggest an increase in the abundance of large fish in 2013 compared to 2005, as well as a notable spikes in recruitment in 2013. Cisco and white suckers also showed recruitment spikes in 2013, but overall, cisco abundance remains similar to 2005 and sucker abundance is still notably lower. northern pike size structure was consistent between years, generally with more fish at all sizes; However, pike CPUE declined approximately 40% from 2012 to 2013. Management actions caused an 83% decrease in nesting cormorants between 2003 and 2013. Over the ten years of active cormorant management, 30,444 nests were sterilized through egg oiling and 8,143 birds (mostly adults) were culled. Since 2010, the number of Indian and Metis domestic netting licenses has approximately doubled. Commercial lake whitefish fisheries have failed to achieve their quota, generally being shut down early for exceeding bycatch tolerances for pike and walleye. Determining the success of the restoration program will require a holistic approach to long-term monitoring of the aquatic ecosystem and the disturbances that threaten its stability. Annual monitoring of the fisheries (FWIN) is recommended to maintain the long-term dataset that will allow assessment of changes in species composition and abundance during the restoration process. In addition, cormorants and their co-nesting species should be monitored to document changes in population size or productivity as the fishery changes. Cormorant management will also likely be required for an indefinite amount of time as the abundant yellow perch population continues to provide a seasonal forage base to support successful breeding of large populations of waterbirds. One of the largest threats to program success moving forward is overharvest of the walleye population during a critical recovery period. Currently, the walleye population is classified as collapsed based on the criteria in Alberta’s Walleye Recovery Plan (Berry 1995). 2014 Lac La Biche Fisheries Restoration Program Summary Report Page ii 2005 to 2013 © 2014 Government of Alberta ESRD/Lac La Biche Fisheries Restoration Program Summary Report, 2005 to 2013 Given this classification the proposed management action is to maintain a catch and release fishery. Increased fishing mortality from domestic and commercial harvest and illegal recreational harvest poses a very serious threat to the continued recovery of the walleye population. Future research should focus on quantifying mortality associated with the commercial, domestic, and recreational harvest, assessing the success of different genetic strains of walleye and partnering with the Lac La Biche County to monitor water quality, lake productivity, and benthic invertebrate productivity. 2014 Lac La Biche Fisheries Restoration Program Summary Report Page iii 2005 to 2013 © 2014 Government of Alberta ESRD/Lac La Biche Fisheries Restoration Program Summary Report, 2005 to 2013 Permission to Quote This report contains preliminary information and interpretations that might be subject to future revisions. Persons who wish to quote from this report, cite it in a bibliography, or use it in any other form must first obtain permission from: Executive Director, LAR Operations Division, Alberta Environment and Sustainable Resource Development; or the author. Keywords: Cormorant, Walleye, FWIN, Lac la Biche Author contact information: Andrea McGregor ([email protected]) Alberta Environment and Sustainable Resource Development, Twin Atria Building, Main Floor, 4999 – 98 Avenue, Edmonton, Alberta, T6B 2X3. Suggested citation: McGregor, A.M. 2014. Lac La Biche Fisheries Restoration Program Summary Report, 2005 to 2013. Alberta Environment and Sustainable Resource Development, Edmonton, Alberta. 2014 Lac La Biche Fisheries Restoration Program Summary Report Page iv 2005 to 2013 © 2014 Government of Alberta ESRD/Lac La Biche Fisheries Restoration Program Summary Report, 2005 to 2013 Acknowledgments I thank C. Davis for his foresight in initiating this research and his mentorship over our 10 years working together. I thank all of the fisheries staff from the Lac la Biche/Waterways area for their help with the fieldwork, especially staff working in the Lac La Biche office. I also thank D. Latty, A. Pruden-Beniuk, C. Dockrill, J. Walker, J. Sloychuk and P. MacMahon for their review of this report. 2014 Lac La Biche Fisheries Restoration Program Summary Report Page v 2005 to 2013 © 2014 Government of Alberta ESRD/Lac La Biche Fisheries Restoration Program Summary Report, 2005 to 2013 Table of Contents Executive Summary ...................................................................................................................................... ii Permission to Quote ..................................................................................................................................... iv Acknowledgments ......................................................................................................................................... v List of Tables ............................................................................................................................................. viii List of Figures ............................................................................................................................................. ix List of Appendices ........................................................................................................................................ x Introduction ................................................................................................................................................... 1 Study Area .................................................................................................................................................... 1 General .................................................................................................................................................. 1 Double-crested cormorant populations ................................................................................................. 2 Lac La Biche Fisheries .......................................................................................................................... 2 Restoration Program Management Actions ................................................................................................... 3 Commercial fishery reductions ............................................................................................................. 3 Sportfishing reductions ......................................................................................................................... 3 Walleye stocking ................................................................................................................................... 3 Cormorant control ................................................................................................................................. 4 Protection of critical fish areas .............................................................................................................. 4 Monitoring ............................................................................................................................................ 4 Restoration Program Management Results ..................................................................................................