Spawning site characterization of Lake Whitefish and Lake Sturgeon in the Fox River, Lake Michigan

Session: Seeing Below the Surface: Quantifying the Underwater Environment with Image Analysis

Christopher Houghton, University of Wisconsin - Green Bay, [email protected]
Patrick Forsythe, University of Wisconsin - Green Bay, [email protected]
Andrew Ransom, University of Wisconsin - Green Bay, [email protected]
Stefan Tucker, University of Wisconsin - Green Bay, [email protected]

Abstract

After years of clean up and remediation the Fox River in lower Green Bay, Lake Michigan, now hosts substantial Lake Whitefish (Coregonus clupeaformis) and Lake Sturgeon (Acipenser fulvescens) spawning runs.  Spawning activity, locations, and larval output of both species were quantified using multiple techniques in 2017 and 2018.  Spawning substrates were classified in GIS using traditional, sidescan, and imaging sonars (ARIS), while larval production was estimated using traditional drift netting.  Habitat utilization by juvenile Lake Sturgeon was assessed using a combination of acoustic tracking of tagged individuals and sidescan sonar mosaics.  Survey results from the Fox River are comapred to spawing surveys from the Menominee, Oconto, and Peshtigo Rivers.  Benefits and limitations of each survey technique will be discussed.