Hydroacoustic Surveys Underestimate Yellow Perch Population Abundance: The Importance of Considering Habitat Use

Abstract

When estimating fish population abundance, it is important to recognize that differing habitat use may cause one gear type to be more effective and less biased than another. We generated and compared population abundance estimates (PE) for adult Yellow Perch Perca flavescens in Crystal Lake, Wisconsin using a spring mini‐fyke net mark–recapture survey and summer hydroacoustic surveys. Mean PE from the spring mark–recapture survey was 11,051 adult Yellow Perch (95% confidence limits of 9,878 and 12,541). This mean was 4.0–8.5 times greater than the range of mean summer hydroacoustic estimates (mean ± 95% CI = 1,291 ± 312 and 2,912 ± 703). Due to Yellow Perch spawning behavior, we assumed that the spring mark–recapture survey sampled the entire adult population, while summer hydroacoustics sampled the postspawn pelagic component. Using the mean of all hydroacoustic surveys (PE = 2,492; n = 5), we estimated that approximately 22% of adult Yellow Perch selected for pelagic habitats postspawn. Our study emphasizes the importance of evaluating gear bias and has implications for future assessments, particularly when the target species may exhibit multiple habitat preferences within a lake.

Seasonal habitat use of yellow perch Perca flavescens in a north‐temperate lake

“…Limited understanding of key fish life‐history attributes, habitat requirements, and interactions within fish communities can lead to misinformed management decisions, particularly when the fish species supports harvest‐oriented fisheries. Management can be further complicated when fish species are habitat generalists and habitat use changes seasonally or among available habitats (Mrnak et al., 2021). Such circumstances often result in an incomplete picture of fish population dynamics and status due to gear limitations and sampling bias in common fisheries surveys.…”

“…Yellow perch Perca flavescens are an ecologically and recreationally important fish species throughout their native and introduced range. Yellow perch are a cool‐water, mid‐trophic level percid found across a diverse range of aquatic ecosystems (Becker 1983; Mrnak et al., 2021; Scott & Crossman, 1973; Thorpe 1977). Yellow perch are commonly targeted and harvested by recreational anglers throughout the year in north‐temperate regions (Embke et al., 2020; Feiner et al., 2020) and serve as a key prey resource for large gamefish (Johnson & Hale, 1977; Pierce, 2012; Sass et al., 2006a).…”

“…Yellow perch persist in a broad range of habitats within and across ecosystem types (Becker, 1983; Dembkowski et al., 2014; Mrnak et al. 2021). This generalist life‐history strategy (i.e.…”

“…littoral‐ and/or pelagic‐orientated) may create issues for fishery managers that rely on accurate estimates of fish population abundance because standard fish sampling gears are typically habitat specific. Indeed, habitat preference and fish behaviour are known to influence sampling accuracy (DuFour et al., 2018; Mrnak et al., 2021; Mullner et al., 1998; Peterson et al., 2004; Rosenberger & Dunham, 2005). Despite this, yellow perch spawn when water temperatures are ∼7–11°C across most habitat and ecosystem types (Becker, 1983; Thorpe, 1977).…”

“…After fertilisation and hatching (∼8–12 mm total length [TL]), age‐0 yellow perch move into pelagic environments before some proportion of the population begins returning to the littoral zone after reaching 25–30 mm in TL (Schael et al., 1991; Whiteside et al., 1985; Wu & Culver, 1992). At this stage of ontogeny, yellow perch are known to use littoral and pelagic habitats within and across system types (Dembkowski et al., 2014; Krieger et al., 1983; Mrnak et al., 2021; Whiteside et al., 1985). Yellow perch growth is sexually dimorphic with females growing faster and achieving longer lengths than males (Liang et al., 2018).…”