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USGS · 70268100

Lake Ontario August gillnet survey and Lake Trout assessment, 2024

Brian O’Malley·Scott P. Minihkeim·Olivia Margaret Mitchinson·Scott David Stahl·Brian Weidel·Michael Connerton·Jessica Goretzke·Lucus Sunderland·Emma Bloomfield·Collin Farrell·Dimitry Gorsky
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Abstract

Lake Ontario Lake Trout ( Salvelinus namaycush ) rehabilitation has been assessed with fishery independent surveys to evaluate program benchmarks and compare observations with management objectives since 1983. These surveys provide information on the abundance, strain composition, and performance of stocked Lake Trout, as well as information on levels of natural recruitment, and Sea Lamprey ( Petromyzon marinus ) wounding rates. In 2024, the gillnet survey occurred in United States (US) and Canadian waters marking the first lake-wide Lake Trout assessment since 2008. Lake Trout catch per unit effort (CPUE) was higher in US than Canadian waters. Recaptures of stocked fish with coded wire tags occurred mostly in US waters, and were composed of the following strains: Lake Champlain, Seneca Lake, Superior Klondike Reef, and Huron Parry Sound. Percentage of naturally produced Lake Trout in US waters continued to be relatively low for mature and immature fish. Interestingly, the percentage of naturally produced Lake Trout was higher in Canadian waters, despite lower total numbers of Lake Trout caught. Sea Lamprey wounding rates on Lake Trout > 432 mm in 2024 were above management targets in US and Canadian waters. Overall, the 2024 survey results suggest that Lake Trout indicators continue to meet some of the management objectives and show spatial differences in overall abundance and the proportion of stocked vs wild fish between the US and Canadian stocks.

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90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 42.89695280777016° to 44.49618203047629° latitude; -80.23446321017573° to -75.75241435838414° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Brian O’Malley, Scott P. Minihkeim, Olivia Margaret Mitchinson, Scott David Stahl, Brian Weidel, Michael Connerton, Jessica Goretzke, Lucus Sunderland, Emma Bloomfield, Collin Farrell, Dimitry Gorsky. 2025. Lake Ontario August gillnet survey and Lake Trout assessment, 2024. https://pubs.usgs.gov/publication/70268100

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