Page 1 Page 2 Page 3 Page 4 Page 5 Page 6 Page 7 Page 8 Page 9 Page 10 Page 11 Page 12 Page 13 Page 14 Page 15 Page 16 Page 17 Page 18 Page 19 Page 20 Page 21 Page 22 Page 23 Page 24• FISHERIES • Despitearoundofadverseweather conditions and hordes of unruly may- flies, GLIFWC electrofishing crews, along with Fond du Lac and Mille Lacs Bandpersonnel,successfullycompleted a juvenile walleye survey in Mille Lacs Lake last spring. During this survey, crewsweretaskedwithcollecting,count- ing, and measuring age-1 walleye that are typically found foraging near the shoreline at night. With up to 78 miles of shoreline, surveying Mille Lacs Lake is no small task! The purpose of this survey is to determine how well walleye are repro- ducing and to gain a sense of walleye survivability during their first year of life. This information provides insight for fisheries biologists when predicting the future abundance of adult walleye, andultimatelyinformswalleyemanage- ment decisions. Currently, juvenile walleye are havingadifficulttimesurvivingintothe adult stage. Although the exact cause for low survivability remains unclear, fisheries biologists suspect that a com- bination of factors such as predation, presenceofinvasivespecies,changesin food availability, and changing climatic conditionscouldbenegativelyaffecting the walleye population. The data collected from this year’s survey show that the 2015 year class (age-1 walleye) is relatively weak; this is consistent with survey data that GLIFWC and Fond du Lac crews col- lected during the fall of 2015. However, the good news is that survey crews observed large numbers of walleye between 11 to 14 inches during the spring survey, indicating that the 2013 year class still appears to be relatively strong. GLIFWC, Fond du Lac, and Mille Lacs personnel plan to conduct a fall juvenile walleye survey during fall of 2016 in order to evaluate the strength of the 2016 year class. On behalf of all the crew leaders, a huge miigwech to everyone involved with the spring 2016 juvenile walleye survey! All your good work is much appreciated! GLIFWC, tribes complete juvenile ogaa survey on Mille Lacs Lake GLIFWC Surveys Lower Eau Claire Lake predators This year, GLIFWC inland fisheries staff worked to estimate the walleye and bass populations on Lower Eau Claire Lake (Douglas County, Wis.) during the spring and through the early summer. The walleye mark-recapture survey was conducted shortly after ice-out with electrofishing gear. For the bass popula- tion estimate, crews electrofished around the lake on multiple days and nights to mark bass with a fin clip, and returned to finish the survey with a recapture run in mid-June. These surveys were completed to give biologists a clearer picture on the predatorcommunitywithinthelake.LowerEauClaireLakeisofparticularinterest to GLIFWC biologists since it has historically had strong walleye reproduction, and fall juvenile walleye surveys have shown a decline in young-of-year walleye surviving to the first fall. GLIFWC biologists have begun to track bass populations more closely since bass have increased while walleye populations have declined in many waters. The mechanism for this fish community change remains unknown. The surveys on Lower Eau Claire will allow biologists to evaluate whether there has been a change in the abundance of the predator fish in the lake. Results will be available after they are exchanged and discussed at the August meeting of tribal and Wisconsin Department of Natural Resources biologists. —Mark Luehring By Ben Michaels GLIFWC Inland Fisheries GLIFWC Inland Fisheries Technician Butch Mieloszyk with a largemouth bass on Lower Eau Claire Lake in northwest Wisconsin. (Ed White photo) MAZINA’IGAN PAGE 8 FALL 2016 Juvenile whitefish and lake trout, targets of GLIFWC small net surveys Keweenaw Peninsula, Mich.—GLIFWC has conducted assess- ments of juvenile whitefish since 1997. Resource managers use the information gathered through biological surveys, along with monitor- ing of the treaty commercial fishery, to assess the health of the fish, which support subsistence and commercial fishers on Lake Superior. GLIFWC Great Lakes Fisheries Biologist Ben Michaels and Technician Mike Plucinski conducted beach seining for juvenile whitefish with the help of three interns: Jalyn LaBine, Callie Kopp, and Marcus Bear. The assessment was conducted this summer in Big Traverse Bay in Michigan’s Upper Peninsula. The counts of juvenile whitefish, which have dropped in recent years, will be compared with results from previous years. Biologists also factor in the results from fall assessments of adult whitefish in their spawning areas. In addition to monitoring whitefish, GLIFWC is also conducting a new micromesh gill net survey off the shores of Big Traverse Bay. The goal of this survey is to monitor the relative abundance of small- sized juvenile lake trout and assess whether the nearby stamp sands are adversely affecting the lake trout population in that area. Stamp sands are mining waste materials, which have been dumped into the lakes and rivers. They contain toxic materials and contaminate the water and change the landscape. In this survey, a 132-foot net, divided into 33 foot panels, each with a different mesh size, ranging from 12.5 to 25.0 millimeters, were used to target fish. Once the nets are lifted, the fish are separated by the mesh size of the nets, then counted, measured, and weighed. Otoliths, hard calcium structures known as earstones, are collected from some of the fish in order to determine their ages. This recent assessment did not yield any juvenile lake trout, however, other species such as rainbow smelt and round whitefish were captured. GLIFWC will continue to sample in different locations around Big Traverse Bay for the next several years. Results from these assessments will be analyzed over the next few months. For more information contact Ben Michaels at smichaels@glifwc.org or at 715-685-2175. By Amanda Plucinski, GLIFWC PIO Intern GLIFWC’s Great Lakes section uses a beach sein to look for juvenile whitefish in Big Traverse Bay in Michigan’s Upper Peninsula. Pictured above are Ben Michaels, GLIFWC Great Lakes Fisheries Biologist (left) and Marcus Bear, GLIFWC Great Lakes section intern. (Amanda Plucinski photo)