Kevin Keretz is a Biological Science Technician based out of Sandusky, OH.
Science and Products
Fisheries research and monitoring activities of the Lake Erie Biological Station, 2020
This report presents biomass-based summaries of fish communities in the West Basin of Lake Erie derived from USGS bottom trawl surveys conducted from 2013 to 2020 during June and September. The survey design provided temporal and spatial coverage that did not exist in the interagency trawl database, and thus complemented the August ODNR-OMNRF effort to reinforce stock assessments with more robust
Improved methods for understanding the role of predation on dreissenid population dynamics
Impacts of dreissenid mussels (Dreissena spp.) on Great Lakes ecosystems are well documented, and a better understanding of mechanisms that cause variation in dreissenid abundance is needed. An outstanding question is how much dreissenid biomass is consumed by fish predation. A significant difficulty for investigating dreissenid consumption by fish is that dreissenids in stomachs are often a mix o
Resource partitioning across a trophic gradient between a freshwater fish and an intraguild exotic
The introduction of exotic species has the potential to cause resource competition with native species and may lead to competitive exclusion when resources are limiting. On the other hand, information is lacking to predict under what alternate trophic conditions coexistence may occur. Comparing diets of native yellow perch Perca flavescens and nonindigenous white perch Morone americana, we examine
Fisheries research and monitoring activities of the Lake Erie Biological Station, 2019
A comprehensive understanding of fish populations and their interactions is the cornerstone of modern fishery management and the basis for Fish Community Goals and Objectives for Lake Erie (Ryan et al. 2003). This report is responsive to U.S. Geological Survey (USGS) obligations via Memorandum of Understanding (MOU) with the Great Lakes Council of Lake Committees (CLC) to provide scientific inform
Fisheries research and monitoring activities of the Lake Erie Biological Station, 2017
This report presents biomass-based summaries of fish communities in western Lake Erie derived from USGS bottom trawl surveys from 2013 to 2017 during June and September. The survey design provided temporal and spatial coverage that does not exist in the interagency trawl database, and thus complemented the August Ohio-Ontario effort to reinforce stock assessments with more robust data. Analyses he
Gradients in Catostomid assemblages along a reservoir cascade
Serial impoundment of major rivers leads to alterations of natural flow dynamics and disrupts longitudinal connectivity. Catostomid fishes (suckers, family Catostomidae) are typically found in riverine or backwater habitats yet are able to persist in impounded river systems. To the detriment of conservation, there is limited information about distribution of catostomid fishes in impounded rivers.
Fisheries research and monitoring activities of the Lake Erie Biological Station, 2013
In 2013, the U.S. Geological Survey’s Lake Erie Biological Station successfully completed large vessel surveys in all three of Lake Erie’s basins. Lake Erie Biological Station’s primary vessel surveys included the Western Basin Forage Fish Assessment and East Harbor Forage Fish Assessment as well as contributing to the cooperative multi-agency Central Basin Hydroacoustics Assessment and the Easter
Lake Erie Fish Community Data, 2013-2021
Assessing the distribution and abundance of both predator and prey (forage) fish species is a cornerstone of ecosystem-based fishery management, and supports decision making that considers food-web interactions. In support of binational Great Lakes fishery management the objectives of this survey were to: provide estimates of densities of key forage and predator species in the western basin of Lak
Diet Data from the Western Basin of Lake Erie Examining White and Yellow Perch, 2012-2016
A fish's diet is the integrated response of multiple ecological interactions including habitat use, foraging behavior, prey community characteristics, and inter-specific interactions. Fish diet samples have quantified how the invasion of white perch into Lake Erie in the early 1950s has influenced interactions with native yellow perch, which are similar in morphology and habitat use. Early researc
Lake Erie Fish Community Data, 2013-2018
Assessing the distribution and abundance of both predator and prey (forage) fish species is a cornerstone of ecosystem-based based fishery management, and supports decision making that considers food-web interactions. In support of binational Great Lakes fishery management the objectives of this survey were to: provide estimates of densities of key forage and predator species in the western basin
Sclerochronology of Walleye Dorsal Spines, 2011-2016
This data release includes both a tabular data set and a zipped file of images. The tabular data set consists of measurements of annuli widths from Walleye dorsal spine thin sections. Walleye spines were sampled non-lethally from fish that were selected for acoustic telemetry tag implantation in several interrelated investigations. The telemetry work was coordinated through the Great Lakes Acousti
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Fisheries research and monitoring activities of the Lake Erie Biological Station, 2020
This report presents biomass-based summaries of fish communities in the West Basin of Lake Erie derived from USGS bottom trawl surveys conducted from 2013 to 2020 during June and September. The survey design provided temporal and spatial coverage that did not exist in the interagency trawl database, and thus complemented the August ODNR-OMNRF effort to reinforce stock assessments with more robustImproved methods for understanding the role of predation on dreissenid population dynamics
Impacts of dreissenid mussels (Dreissena spp.) on Great Lakes ecosystems are well documented, and a better understanding of mechanisms that cause variation in dreissenid abundance is needed. An outstanding question is how much dreissenid biomass is consumed by fish predation. A significant difficulty for investigating dreissenid consumption by fish is that dreissenids in stomachs are often a mix oResource partitioning across a trophic gradient between a freshwater fish and an intraguild exotic
The introduction of exotic species has the potential to cause resource competition with native species and may lead to competitive exclusion when resources are limiting. On the other hand, information is lacking to predict under what alternate trophic conditions coexistence may occur. Comparing diets of native yellow perch Perca flavescens and nonindigenous white perch Morone americana, we examineFisheries research and monitoring activities of the Lake Erie Biological Station, 2019
A comprehensive understanding of fish populations and their interactions is the cornerstone of modern fishery management and the basis for Fish Community Goals and Objectives for Lake Erie (Ryan et al. 2003). This report is responsive to U.S. Geological Survey (USGS) obligations via Memorandum of Understanding (MOU) with the Great Lakes Council of Lake Committees (CLC) to provide scientific informFisheries research and monitoring activities of the Lake Erie Biological Station, 2017
This report presents biomass-based summaries of fish communities in western Lake Erie derived from USGS bottom trawl surveys from 2013 to 2017 during June and September. The survey design provided temporal and spatial coverage that does not exist in the interagency trawl database, and thus complemented the August Ohio-Ontario effort to reinforce stock assessments with more robust data. Analyses heGradients in Catostomid assemblages along a reservoir cascade
Serial impoundment of major rivers leads to alterations of natural flow dynamics and disrupts longitudinal connectivity. Catostomid fishes (suckers, family Catostomidae) are typically found in riverine or backwater habitats yet are able to persist in impounded river systems. To the detriment of conservation, there is limited information about distribution of catostomid fishes in impounded rivers.Fisheries research and monitoring activities of the Lake Erie Biological Station, 2013
In 2013, the U.S. Geological Survey’s Lake Erie Biological Station successfully completed large vessel surveys in all three of Lake Erie’s basins. Lake Erie Biological Station’s primary vessel surveys included the Western Basin Forage Fish Assessment and East Harbor Forage Fish Assessment as well as contributing to the cooperative multi-agency Central Basin Hydroacoustics Assessment and the Easter - Data
Lake Erie Fish Community Data, 2013-2021
Assessing the distribution and abundance of both predator and prey (forage) fish species is a cornerstone of ecosystem-based fishery management, and supports decision making that considers food-web interactions. In support of binational Great Lakes fishery management the objectives of this survey were to: provide estimates of densities of key forage and predator species in the western basin of LakDiet Data from the Western Basin of Lake Erie Examining White and Yellow Perch, 2012-2016
A fish's diet is the integrated response of multiple ecological interactions including habitat use, foraging behavior, prey community characteristics, and inter-specific interactions. Fish diet samples have quantified how the invasion of white perch into Lake Erie in the early 1950s has influenced interactions with native yellow perch, which are similar in morphology and habitat use. Early researcLake Erie Fish Community Data, 2013-2018
Assessing the distribution and abundance of both predator and prey (forage) fish species is a cornerstone of ecosystem-based based fishery management, and supports decision making that considers food-web interactions. In support of binational Great Lakes fishery management the objectives of this survey were to: provide estimates of densities of key forage and predator species in the western basinSclerochronology of Walleye Dorsal Spines, 2011-2016
This data release includes both a tabular data set and a zipped file of images. The tabular data set consists of measurements of annuli widths from Walleye dorsal spine thin sections. Walleye spines were sampled non-lethally from fish that were selected for acoustic telemetry tag implantation in several interrelated investigations. The telemetry work was coordinated through the Great Lakes Acousti - News