Event Title
Population Status of Lake Sturgeon in the Muskegon River, MI
Location
Hager-Lubbers Exhibition Hall
Description
PURPOSE: The Muskegon River is a Lake Michigan tributary that supports a remnant population of lake sturgeon (Acipenser fulvescens). We have assessed the status of this population since 2008. METHODS AND MATERIALS: Each spring, adult lake sturgeon were sampled via gill netting in Muskegon Lake and boat electrofishing in the Muskegon River. Juvenile lake sturgeon were sampled with gill nets in Muskegon Lake each year during August - December. Finally, we sampled larval drift in the Muskegon River to assess reproductive success of the population. RESULTS: During 2008 – 2012, we captured 205 unique individual lake sturgeon. Age-structure analysis of captured lake sturgeon (n = 160) indicates 26 year classes are represented among captured individuals, with the age of the majority (93.1 % of aged fish) of individuals being 21 years or less. Seventy-eight unique adult lake sturgeon (range = 103.5 – 191.0 cm total length [TL]) were captured during this study; captures ranged from 9 to 25 adults on any given year, which suggests the number of adults in the annual spawning run is relatively low. Larval lake sturgeon were successfully captured in 2009 - 2011 (n = 50; range = 13.0 - 21.5 mm TL). Juvenile lake sturgeon were captured each year of the study in Muskegon Lake (n = 127; range = 23.1 to 98.2 cm TL). CONCLUSIONS: Our results suggest the spawning run in the Muskegon River is small, with evidence of natural reproduction.
Population Status of Lake Sturgeon in the Muskegon River, MI
Hager-Lubbers Exhibition Hall
PURPOSE: The Muskegon River is a Lake Michigan tributary that supports a remnant population of lake sturgeon (Acipenser fulvescens). We have assessed the status of this population since 2008. METHODS AND MATERIALS: Each spring, adult lake sturgeon were sampled via gill netting in Muskegon Lake and boat electrofishing in the Muskegon River. Juvenile lake sturgeon were sampled with gill nets in Muskegon Lake each year during August - December. Finally, we sampled larval drift in the Muskegon River to assess reproductive success of the population. RESULTS: During 2008 – 2012, we captured 205 unique individual lake sturgeon. Age-structure analysis of captured lake sturgeon (n = 160) indicates 26 year classes are represented among captured individuals, with the age of the majority (93.1 % of aged fish) of individuals being 21 years or less. Seventy-eight unique adult lake sturgeon (range = 103.5 – 191.0 cm total length [TL]) were captured during this study; captures ranged from 9 to 25 adults on any given year, which suggests the number of adults in the annual spawning run is relatively low. Larval lake sturgeon were successfully captured in 2009 - 2011 (n = 50; range = 13.0 - 21.5 mm TL). Juvenile lake sturgeon were captured each year of the study in Muskegon Lake (n = 127; range = 23.1 to 98.2 cm TL). CONCLUSIONS: Our results suggest the spawning run in the Muskegon River is small, with evidence of natural reproduction.