An exploratory fishery was carried out in the Mackenzie River Delta between 1989 and 1993 at the request of the Inuvik Hunters and Trappers Committee to assess the commercial fishery potential in this area. Data collected during this exploratory fishery was used in two technical reports. Broad whitefish were the target species of this fishery (DFO Technical Report 2180), however other species such as northern pike, inconnu, and lake whitefish were also harvested (DFO Technical Report 2330). Biological data from broad whitefish (fork length, age, gonadosomatic index and instantaneous mortality) were analyzed to assess the impact of an exploratory fishery in the Mackenzie River Delta. The data were collected using variable mesh experimental gill nets and commercial harvesters' 139 mm (5.5”) mesh gill nets. The data suggest that the broad whitefish population might be separated, with larger mature spawners gathering in the main channels prior to spawning and smaller, immature or resting fish staying in side channels away from strong currents. From this analysis we conclude that the size and structure of the broad whitefish population(s) found in this area are stable at the current level of total harvest (commercial and subsistence combined) There may be room for increased harvests but to what level is uncertain. Biological data from northern pike, inconnu, and lake whitefish were analyzed to assess the impact of the fishery on population abundance and structure. All three by catch species support subsistence fisheries in the Mackenzie Delta. lnconnu and lake whitefish migrate substantial distances, crossing land claim borders and are likely fished by a variety of user groups. Northern pike, on the other hand tend to be non-migratory with localized populations that are mainly fished by people living in the near vicinity. A concern was that commercial fishing pressure might reduce the numbers of fish available to subsistence users. Based on trends in size and age frequency, age at maturity, sex ratio, growth rates, and mortality rates, we conclude that inconnu and lake whitefish populations in the Mackenzie Delta have remained healthy and stable at the current harvest levels, however northern pike populations showed a decrease in the proportion of older fish, possibly indicating over-fishing of local stocks. lnconnu and lake whitefish may be able to withstand increased harvest, but to what extent is unknown, given that little reliable information is available on subsistence harvest levels in this region. Increasing harvest levels of pike may be risky and we suggest that a reduction of current commercial harvest quotas be considered.

Recent declines in Lake Whitefish population abundance has prompted research to identify underlying mechanisms controlling survival of early life stages in the Great Lakes. In Lake Erie, the recruitment bottleneck window determining year class strength of Lake Whitefish occurs during the first growing season, suggesting that availability of prey could be controlling year class strength. Therefore, spatial and seasonal larval Lake Whitefish distribution, diet, and environmental zooplankton (potential prey) were collected to evaluate larval Lake Whitefish diets at 31 locations in the western basin during 2017, 2018, and 2021. We removed gut tracks of larval lake whitefish and identified diet items to lowest possible taxon. Zooplankton samples were taken in the field and identified in the lab. Zooplankton were identified to the taxonomic level of large cladoceran, small cladoceran, cyclopoid copepods, calanoid copepods, nauplii, and rotifer. Diet item body length was measured for the first 20 individuals of each prey item in each sample.

Recent declines in Lake Whitefish population abundance has prompted research to identify underlying mechanisms controlling survival of early life stages in the Great Lakes. In Lake Erie, the recruitment bottleneck window determining year class strength of Lake Whitefish occurs during the first growing season, suggesting that availability of prey could be controlling year class strength. Therefore, spatial and seasonal larval Lake Whitefish distribution, diet, and environmental zooplankton (potential prey) were collected to evaluate larval Lake Whitefish diets at 31 locations in the western basin during 2017, 2018, and 2021. We removed gut tracks of larval lake whitefish and identified diet items to lowest possible taxon. Zooplankton samples were taken in the field and identified in the lab. Zooplankton were identified to the taxonomic level of large cladoceran, small cladoceran, cyclopoid copepods, calanoid copepods, nauplii, and rotifer. Diet item body length was measured for the first 20 individuals of each prey item in each sample.

This data release presents catch and effort data for Cisco Coregonus artedi and Lake Whitefish Coregonus clupeaformis commercial gill net fisheries in State of Michigan waters of Lakes Superior, Michigan, and Huron during 1929-1970. The data were used to determine if Cisco and Lake Whitefish relative abundance (commercial gill net catch per effort) were correlated (positive and negative) during the historical period. The file is in .csv format and contains columns for: (1) lake (LAKE); (2) commercial fishery management unit (MU); (3) year (YEAR); (4) gill net material used to target Lake Whitefish (WF_MAT); (5) gill net material used to target Cisco (CS_MAT); (6) gill net conversion factors (multipliers) used to convert effort into linen and cotton gill net equivalents for Lake Whitefish (WF_CF); (7) gill net conversion factors (multipliers) used to convert effort into linen and cotton gill net equivalents for Cisco (CS_CF); (8) catch (kg) of Lake Whitefish (WF_KG); (9) catch (kg) of Cisco (CS_KG); (10) corrected effort (km of net) for Lake Whitefish (WF_KM); (11) corrected effort (km of net) for Cisco (CS_KM); (12) corrected catch per effort (kg per km of net) for Lake Whitefish (WF_CPE); (13) corrected catch per effort (kg per km of net) for Cisco (CS_CPE); (14) loge-transformed corrected catch per effort for Lake Whitefish (LN_WF_CPE); (15) loge-transformed corrected catch per effort for Cisco (LN_CS_CPE); (16) standardized Z-scores based on loge-transformed corrected catch per effort for Lake Whitefish (WF_Z); (17) standardized Z-scores based on loge-transformed corrected catch per effort for Cisco (CS_Z); and (18) whether individual data points were removed prior to analyses based on values of corrected effort for either species (i.e., WF_KM or CS_KM) that fell outside the 2.5-97.5 percentile range for all available unit- and species-specific effort data pooled (E_FILTER). Gill net conversion factors were required because different gill net materials with different efficiencies were used throughout the historical period. Efficiencies increased over time with the introduction of each new gill net material (i.e., linen and cotton to nylon-multifilament to nylon-monofilament). All corrected data were expressed as linen and cotton gill net equivalents. To express data as linen and cotton gill net equivalents, nylon-monofilament and nylon-multifilament gill net effort were multiplied by species-, lake-, and year-specific gill net conversion factors (WF_CF and CS_CF). Efficiency curves can be generated for each species and lake by plotting gill net conversion factors over time (i.e., WF_CF and CS_CF vs. YEAR). It is worth noting that gill net conversion factors (WF_CF and CS_CF) were based on data collected prior to increases in water clarity throughout all three lakes and relative efficiencies may have changed in recent years. We encourage users to exercise caution when applying these conversion factors to more recent data (post-1970s). The effort filter was used to ensure that individual data points used for analyses (i.e., paired Cisco–Lake Whitefish catch per effort) were not based on unusually high or low levels of targeted effort for either species.

This data contains coordinate locations for suspected historical spawning locations of lake whitefish (Coregonus clupeaformis) and cisco (Coregonus artedi) across the Lake Erie basin, including the Detroit River, Lake St. Clair, and the St. Clair River. Data points were summarized using ArcGIS 10.5. Data came from published and unpublished sources cited in the Atlas of the Spawning and Nursery Areas of Great Lakes Fishes (Goodyear et al. 1982) and other sources as described. Data points included were specific locations described as having the presence of eggs or spawning fish. Pseudo-absence data used for comparison purposes are also provided in this data release.

This data contains coordinate locations for suspected historical spawning locations of lake whitefish (Coregonus clupeaformis) and cisco (Coregonus artedi) across the Lake Erie basin, including the Detroit River, Lake St. Clair, and the St. Clair River. Data points were summarized using ArcGIS 10.5. Data came from published and unpublished sources cited in the Atlas of the Spawning and Nursery Areas of Great Lakes Fishes (Goodyear et al. 1982) and other sources as described. Data points included were specific locations described as having the presence of eggs or spawning fish. Pseudo-absence data used for comparison purposes are also provided in this data release.

These data include a field study of the sediment hardness and fish egg density (walleye [Sander vitreus] and lake whitefish [Coregonus clupeaformis]) after sediment cleaning treatments (propulsion sled or hydro-jet sled) conducted at two reef locations in Saginaw Bay, Lake Huron, during 2018 and 2019. The data includes the year, species, reef, treatment type (jet, fan, control), number of eggs, and egg density in the treatment area. Relative sediment hardness for the treatment areas assessed before and after sediment cleaning experiments is provided. Additionally, walleye eggs were collected from Brookville Reservoir, Indiana, and incubated at the aquaculture research laboratory at Purdue University (West Lafayette, Indiana) to determine the effect of sediment cover on egg hatching success rate. The incubated eggs were exposed to different sediment types and levels of sediment coverage intensity. The data contains the year, treatment, parental female length (2019 only), number of walleye hatched, and egg diameter (2019 only) collected in the laboratory study.

These data include a field study of the sediment hardness and fish egg density (walleye [Sander vitreus] and lake whitefish [Coregonus clupeaformis]) after sediment cleaning treatments (propulsion sled or hydro-jet sled) conducted at two reef locations in Saginaw Bay, Lake Huron, during 2018 and 2019. The data includes the year, species, reef, treatment type (jet, fan, control), number of eggs, and egg density in the treatment area. Relative sediment hardness for the treatment areas assessed before and after sediment cleaning experiments is provided. Additionally, walleye eggs were collected from Brookville Reservoir, Indiana, and incubated at the aquaculture research laboratory at Purdue University (West Lafayette, Indiana) to determine the effect of sediment cover on egg hatching success rate. The incubated eggs were exposed to different sediment types and levels of sediment coverage intensity. The data contains the year, treatment, parental female length (2019 only), number of walleye hatched, and egg diameter (2019 only) collected in the laboratory study.

The following data release contains coordinates for suspected historical spawning locations of lake whitefish (Coregonus clupeaformis) and cisco (Coregonus artedi) across the Lake Ontario basin, including the Niagara River and St. Lawrence River. These data were gathered from published and unpublished sources cited in the Atlas of the Spawning and Nursery Areas of Great Lakes Fishes (Goodyear et al. 1982) and other sources as described. We define "spawning locations" as areas having eggs or spawning fish present. When available the data also contain substrate and depth information. Pseudo-absence data used for comparison purposes are also provided in this data release. Data points were summarized using ArcGIS 10.5

The following data release contains coordinates for suspected historical spawning locations of lake whitefish (Coregonus clupeaformis) and cisco (Coregonus artedi) across the Lake Ontario basin, including the Niagara River and St. Lawrence River. These data were gathered from published and unpublished sources cited in the Atlas of the Spawning and Nursery Areas of Great Lakes Fishes (Goodyear et al. 1982) and other sources as described. We define "spawning locations" as areas having eggs or spawning fish present. When available the data also contain substrate and depth information. Pseudo-absence data used for comparison purposes are also provided in this data release. Data points were summarized using ArcGIS 10.5