Page 10 - Vermilion Lake Association Spring 2021 Newsletter

fish/net ranked as the third highest catch rate histor- ically in that basin. The West Vermilion catch rate of 16.0 fish/net ranked as the second highest catch rate historically in that basin.
The average length of walleyes captured in the fall 2020 gill-net survey was about 14 inches. It was
the smallest average size since 2008, which can
be attributed to the recent strong year classes that produced exceptionally high catches of fish under 15 inches throughout the lake. These fish should pro- vide substantial catch and harvest opportunities over the next several years. Additionally, high catch rates of fish 20 inches and larger will continue to provide memorable catch opportunities throughout the lake while also ensuring plenty of broodstock.
Walleyes captured in gill nets in 2020 ranged from 0 to 23 years old. Lakewide catch rates of age-0 (2020 year-class), age-1 (2019 year-class), age-2 (2018 year-class), age-4 (2016 year-class), age-5 (2015 year- class), age-7 (2013 year-class), and ages-8 and older fish were at or above historical averages. The catch rate of age-2 fish was the highest ever observed for an age-2 cohort. This follows an above-average catch rate of that year-class as an age-1 cohort in 2019, suggesting strong recruitment. The catch rate of fish ages-8 and older exceeded the 75th percentile for the second consecutive year and for the 10th time in 11 years. Following implementation of size protective walleye regulations in 2006, the catch rate of these
older fish has drastically increased.
The most recent strong walleye year-class was produced lakewide in 2016 and preliminary esti- mates indicate 2018 and 2019 could also be strong year-classes. The most recent weak year-class oc- curred lakewide in 2017. In East Vermilion, the most recent strong year-class was produced in 2016 and preliminary estimates indicate 2019 could be strong. The last weak year-class was produced in 2017. In West Vermilion, consistent moderate to strong re- cruitment has occurred annually since the last weak year-class in 2013. The 2018 cohort will likely be the first strong year-class in West Vermilion since 2014 and a potential banner year-class overall.
Fall electrofishing provides useful information on abundance and growth of young-of-the-year (YOY) walleyes near the end of their first growing season. In Lake Vermilion, both the catch rate of YOY walleyes and average length of fish captured help predict fu- ture year-class strength. In 2020, the lakewide catch rate of YOY walleyes of 72.0 fish/hour fell below the 25th percentile of previous surveys. Below average catches of YOY fish occurred in East Vermilion while catches below the 25th percentile were recorded in West Vermilion. The average length of fish captured lakewide was 6.3 inches, which was the highest aver- age size ever recorded.
10 The Vermilion, Spring 2021