Technical Fisheries Committee Administrative Report 2013: Status of Lake Trout and Lake Whitefish Populations in the 1836 Treaty-Ceded Waters of Lakes Superior, Huron, and Michigan, with Recommended Yield and Effort Levels for 2013 A Report Submitted by the Modeling Subcommittee to the Technical Fisheries Committee D.C. Caroffino (Michigan Department of Natural Resources) S.J. Lenart (United States Fish and Wildlife Service) Editors Recommended citation formats: Entire report: Modeling Subcommittee, Technical Fisheries Committee. 2013. Technical Fisheries Committee Administrative Report 2013: Status of Lake Trout and Lake Whitefish Populations in the 1836 Treaty-Ceded Waters of Lakes Superior, Huron and Michigan, with Recommended Yield and Effort Levels for 2013. http://www.michigan.gov/greatlakesconsentdecree Section: Caroffino, D.C. and Lenart, S.J. 2013. Executive Summary in Caroffino, D.C., and Lenart, S.J., eds. Technical Fisheries Committee Administrative Report 2013: Status of Lake Trout and Lake Whitefish Populations in the 1836 Treaty-Ceded Waters of Lakes Superior, Huron and Michigan, with Recommended Yield and Effort Levels for 2013. http://www.michigan.gov/greatlakesconsentdecree 2 Table of Contents Executive Summary .................................................................................................................. 4 Management Unit Descriptions ................................................................................................. 9 Status of Lake Trout Populations ............................................................................................ 16 Lake Superior .......................................................................................................................... 16 MI-5 (Marquette) ................................................................................................................. 16 MI-6 (Munising)................................................................................................................... 17 MI-7 (Grand Marais) ............................................................................................................ 18 Lake Huron .............................................................................................................................. 19 MH-1 (Northern Lake Huron) .............................................................................................. 19 MH-2 (North-Central Lake Huron) ...................................................................................... 20 Lake Michigan ......................................................................................................................... 21 MM-123 (Northern Treaty Waters) ...................................................................................... 21 MM-4 (Grand Traverse Bay) ............................................................................................... 22 MM-5 (Leelanau Peninsula to Arcadia) ............................................................................... 23 MM-67 (Southern Treaty Waters)........................................................................................ 24 Status of Lake Whitefish Populations ..................................................................................... 25 Lake Superior .......................................................................................................................... 25 WFS-04 (Marquette-Big Bay) .............................................................................................. 25 WFS-05 (Munising) ............................................................................................................. 27 WFS-06 (Grand Marais) ...................................................................................................... 28 WFS-07 (Tahquamenon Bay) .............................................................................................. 29 WFS-08 (Brimley) ............................................................................................................... 30 Lake Huron .............................................................................................................................. 32 Northern Huron (WFH-01 to WFH-04) ............................................................................... 32 WFH-05 (Alpena) ................................................................................................................ 34 Lake Michigan ......................................................................................................................... 36 WFM-01 (Bays De Noc) ...................................................................................................... 36 WFM-02 (Manistique) ......................................................................................................... 38 WFM-03 (Naubinway) ......................................................................................................... 40 WFM-04 (Beaver Island) ..................................................................................................... 42 WFM-05 (Grand Traverse Bay) ........................................................................................... 44 WFM-06 (Leland) ................................................................................................................ 46 WFM-07 (Manistee to Pentwater)........................................................................................ 48 WFM-08 (Muskegon) .......................................................................................................... 49 3 EXECUTIVE SUMMARY Prepared by David C. Caroffino and Stephen J. Lenart This document outlines the status of lake reduced narratives within each individual trout and lake whitefish stocks as assessed by unit summary; the 2000 Consent Decree’s Modeling standardized graphical output; Subcommittee. The format of this report has shortened summary tables; been substantially altered from all previous management unit descriptions included in a annual reports. The objective was to provide a stand-alone section; more succinct, consistent summary without removal of the Stock Assessment Models and losing focus on the primary purposes, which are Priority Work for Future Assessments to 1) briefly describe the status of each stock in sections. These will be periodically updated the context of establishing harvest limits and included in future versions of this according to the terms of the Consent Decree report. The most recent version of these and 2) document important technical changes in sections are available in the 2012 report: the stock assessment process. The most http://www.michigan.gov/greatlakesconsent substantive changes include: decree Table 1. Yield and effort limits for 2013. Management Model-generated yield Actual yield Gill net limit Species Lake unit limit (lb) limit (lb) (ft) Lake Superior MI-5 133,196 133,196 NA trout MI-6 162,548 162,548 4,131,000 MI-7 73,990 73,990 2,988,000 Huron MH-1 485,163 471,500 13,100,000 MH-2 131,191 131,191 NA Michigan MM-123 0 503,000 15,729,000 MM-4 91,696 177,853 1,248,000 MM-5 67,214 98,000 192,000 MM-67 465,272 465,272 NA Lake Superior WFS-04 112,000 112,000 NA whitefish WFS-05 437,000 437,000 NA WFS-06 No model estimate 210,000 NA WFS-07 376,900 376,900 NA WFS-08 262,600 262,600 NA Huron Northern NA Huron 356,400 485,730 WFH-05 768,300 768,300 NA Michigan WFM-01 1,716,000 2,000,000 NA WFM-02 494,700 494,700 NA WFM-03 1,598,500 1,598,500 NA WFM-04 634,000 634,000 NA WFM-05 365,000 365,000 NA WFM-06 132,200 250,000 NA WFM-07 No model estimate 500,000 NA WFM-08 492,200 1,400,000 NA 4 Lake Trout thus our projections suggest yield could be In 2013, the MSC continued the lake trout increased in all modeled Lake Superior stocks in model rotation strategy first implemented in 1836 waters. There have been no efforts to fit a 2009. Full stock assessments were not stock assessment model for lake trout in MI-8 of completed for lake trout units MI-7 and MM-67. Lake Superior because this is a deferred area. Instead, output from the 2012 assessment was Widespread natural reproduction of lake used along with current harvest and sea lamprey trout continues to be evident in all Lake Huron mortality information to project the population data sources. In 2012, unclipped fish forward another year. The mortality provisions represented 23% of the commercial fishery in of the Consent Decree were then applied to the the U.S. waters of northern Lake Huron and projected population to calculate harvest limits approximately 40% of the recreational lake trout for 2013. Full stock assessments for these units fishery. In the Canadian commercial fishery the are next scheduled for 2015. Due to significant proportion of unclipped fish exceeded 60%. changes in both model structure and stock Since these wild fish are predominately younger dynamics, a full assessment was conducted for than age 8, hatchery fish still represent the lake trout unit MH-2, a unit which had largest proportion of the adult stock, particularly previously been included in the rotation strategy. in US waters. To account for the continued This unit will be evaluated on an annual basis presence of wild fish in the population, the Lake for inclusion in the rotation plan. Huron assessments are now structured to include In Lake Superior, lean lake trout are self- both wild and hatchery fish (see Technical sustaining, and the SCAA models and target Changes section for details). mortality rates apply to these wild fish in three