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.

Egg mat retention trials were conducted with walleye (Stizostedion vitreum) and lake whitefish (Coregonus clupeaformis) eggs in an experimental flume tank, seeded directly on egg mats (test retention efficiency) and hand dispersed in flowing flume water to simulate spawning over egg mats (test capture efficiency) with and without alternate substrate. In the field study, we measured number of eggs collected on mats and with bottom drift nets in the Detroit River to compare capture effectiveness. The field collection data describe the number, date of collection, and exact collection location of target species (walleye and lake whitefish). The flume trial data include number of eggs retained or collected, water velocity, and substrate during the flume trials.

Egg mat retention trials were conducted with walleye (Stizostedion vitreum) and lake whitefish (Coregonus clupeaformis) eggs in an experimental flume tank, seeded directly on egg mats (test retention efficiency) and hand dispersed in flowing flume water to simulate spawning over egg mats (test capture efficiency) with and without alternate substrate. In the field study, we measured number of eggs collected on mats and with bottom drift nets in the Detroit River to compare capture effectiveness. The field collection data describe the number, date of collection, and exact collection location of target species (walleye and lake whitefish). The flume trial data include number of eggs retained or collected, water velocity, and substrate during the flume trials.

A long-term, multi-season, fish egg sampling program is conducted annually on the Detroit, Saint Clair, and Saint Marys rivers to identify where productive fish spawning habitat currently exists and evaluate habitat restoration projects. Egg mats were placed on the river bottom during the spring and fall at historic spawning areas, candidate fish spawning habitat restoration sites, and completed spawning habitat restoration sites throughout the rivers. Egg mats were placed in US and Canadian waters. Widespread evidence was found of lithophilic spawning by numerous native fish species, including walleye (Sander vitreus), lake whitefish (Coregonus clupeaformis), lake sturgeon (Acipenser fulvescens), suckers (Family: Catostomidae), and trout-perch (Percopsis omiscomaycus). The data describe the number, density, date of collection, and exact collection location of fish eggs collected in the St. Clair (2010-2024), Detroit (2005-2024), and St. Marys rivers (2018-2022).

A long-term, multiseason, fish egg sampling program is conducted annually on the Detroit, Saint Clair, and Saint Marys rivers to identify where productive fish spawning habitat currently exists and evaluate habitat restoration projects. Egg mats were placed on the river bottom during the spring and fall at historic spawning areas, candidate fish spawning habitat restoration sites, and completed spawning habitat restoration sites throughout the rivers. Widespread evidence was found of lithophilic spawning by numerous native fish species, including walleye (Sander vitreus), lake whitefish (Coregonus clupeaformis), lake sturgeon (Acipenser fulvescens), suckers (Family: Catostomidae), and trout-perch (Percopsis omiscomaycus). The data describe the number, density, date of collection, and exact collection location of fish eggs collected in the St. Clair (2010-2022), Detroit (2005-2022), and St. Marys rivers (2018-2022).

A long-term, multiseason, fish egg sampling program is conducted annually on the Detroit, Saint Clair, and Saint Marys rivers to identify where productive fish spawning habitat currently exists and evaluate habitat restoration projects. Egg mats were placed on the river bottom during the spring and fall at historic spawning areas, candidate fish spawning habitat restoration sites, and completed spawning habitat restoration sites throughout the rivers. Widespread evidence was found of lithophilic spawning by numerous native fish species, including walleye (Sander vitreus), lake whitefish (Coregonus clupeaformis), lake sturgeon (Acipenser fulvescens), suckers (Family: Catostomidae), and trout-perch (Percopsis omiscomaycus). The data describe the number, density, date of collection, and exact collection location of fish eggs collected in the St. Clair (2010-2022), Detroit (2005-2022), and St. Marys rivers (2018-2022).

The fish length and stomach content prey count and prey length of age-0 Lake Whitefish (Coregonus clupeaformis) were collected in several regions of Lake Huron, Great Lakes between 2014-06-18 and 2018-07-05. These fish were collected by the U.S. Fish and Wildlife Service (Alpena, MI) using Neuston nets or beach seines as part of routine larval coregonine surveys. Subsamples of fish were transferred to NOAA/GLERL where diet analysis took place.

Tributaries support spawning habitats for three of the four major sub-stocks of Lake Erie walleye (Sander vitreus). Despite a history of anthropogenic degradation and the extirpation of other potamodromous species, the Maumee River, OH continues to support one of the largest fish migrations in the Laurentian Great Lakes. To determine if spawning habitat availability and quality could limit production of Maumee River walleye, a habitat suitability model based on river bottom substrates and water depth was created for the lower 51 km of the Maumee River, and the distribution and relative abundance of walleye eggs deposited in a 25-km stretch of river were assessed. Walleye eggs were collected using a diaphragm pump at 7-10 sites two to three times per week from 1 April–7 May 2014 and from 24 March–5 May 2015, beginning shortly after ice out and continuing until early May when spawning ceased. To quantify spawning habitat within the Maumee River, a side-scan sonar unit and a bow-mounted transducer were used to identify river bottom substrate types. Substrate composition was visually delineated by drawing polygons around substrate patches and assigning the dominant substrate classification to each polygon in GIS software. Visual substrate surveys were conducted throughout the study area during June and September 2014–2016 and were used to inform the substrate classifications made by the side-scan sonar. Water depth and water velocity were modeled in the hydraulic modeling program HEC-RAS based on topographic data and water level gage data. Known walleye spawning habitat preferences from peer-reviewed literature were used to assign habitat suitability index (HSI) values from two different HSI models to substrate, modeled water depth, and modeled water velocity for spawning adult walleye, and habitat suitability maps were generated.

Tributaries support spawning habitats for three of the four major sub-stocks of Lake Erie walleye (Sander vitreus). Despite a history of anthropogenic degradation and the extirpation of other potamodromous species, the Maumee River, OH continues to support one of the largest fish migrations in the Laurentian Great Lakes. To determine if spawning habitat availability and quality could limit production of Maumee River walleye, a habitat suitability model based on river bottom substrates and water depth was created for the lower 51 km of the Maumee River, and the distribution and relative abundance of walleye eggs deposited in a 25-km stretch of river were assessed. Walleye eggs were collected using a diaphragm pump at 7-10 sites two to three times per week from 1 April–7 May 2014 and from 24 March–5 May 2015, beginning shortly after ice out and continuing until early May when spawning ceased. To quantify spawning habitat within the Maumee River, a side-scan sonar unit and a bow-mounted transducer were used to identify river bottom substrate types. Substrate composition was visually delineated by drawing polygons around substrate patches and assigning the dominant substrate classification to each polygon in GIS software. Visual substrate surveys were conducted throughout the study area during June and September 2014–2016 and were used to inform the substrate classifications made by the side-scan sonar. Water depth and water velocity were modeled in the hydraulic modeling program HEC-RAS based on topographic data and water level gage data. Known walleye spawning habitat preferences from peer-reviewed literature were used to assign habitat suitability index (HSI) values from two different HSI models to substrate, modeled water depth, and modeled water velocity for spawning adult walleye, and habitat suitability maps were generated.

This dataset contains laboratory experiment data that were collected to examine the effects of ocean acidification on hatch size and larval growth of walleye pollock (Theragra chalcogramma). Rising atmospheric concentrations of CO2 are predicted to decrease the pH of high-latitude oceans by 0.3-0.5 units by 2100. Because of their limited capacity for ion exchange, embryos and larvae of marine fishes are predicted to be more sensitive to elevated CO2 than juveniles and adults. Eggs and larvae of walleye pollock (Theragra chalcogramma) were incubated across a broad range of CO2 levels (280-2100 matm) to evaluate sensitivity in this critical resource species. Slightly elevated CO2 levels (450 matm) resulted in earlier hatching times, but differences among egg batches were greater than those observed across CO2 treatments. Egg batches differed significantly in size-at-hatch metrics, but we observed no consistent effect of CO2 level. In three independent experiments, walleye pollock were reared at ambient and elevated CO2 levels through the early larval stage (to 30 days post-hatch). Across trials, there were only minor effects of CO2 level on size and growth rate, but fish in the ambient treatments tended to be slightly smaller than fish reared at elevated CO2 levels. These results suggest that growth potential of early life stages of walleye pollock is resilient with respect to the direct physiological effects of ocean acidification.