Comparison of Electrofishing Techniques and Effort Allocation across Diel Time Periods, Seasons, Sites, and Habitat in the Ohio Coastal Waters of Western Lake Erie

Abstract

Coastal (<3‐m depth) and nearshore (3–15‐m depth) zones of large freshwater lakes are generally rich in complex habitats that are important for fisheries, but they are often highly degraded and understudied. We identified spatial and temporal sampling efficiencies for monitoring coastal fish communities in a large freshwater lake by use of electrofishing. During 2011 and 2012, we sampled 21 coastal sites in Lake Erie's western basin via daytime and nighttime electrofishing with multiple replicates throughout the summer sampling season. Nighttime electrofishing captured more species and more individuals with less effort than daytime electrofishing; nighttime electrofishing conducted early in the season (i.e., late spring and early summer) was more efficient than that conducted late in the season (i.e., late summer and early fall). A sampling design based on 500 m of shoreline per site required fewer sites and person‐hours to attain 65% and 75% of total species richness (6 and 11 sites, respectively) than a design that used 100 m/site. A 300‐m/site design was more efficient at targeting 90% of total species richness. Targeting of wetland habitat increased the number of species captured but missed species that were only found at other habitat types. A sampling design that targeted 11 sites (75% of species richness) sufficiently described fish community metrics (e.g., number of tolerant species) since the design captured nearly all fish species that were relevant to each metric. This study provides the foundation for a coastal monitoring program in western Lake Erie and serves as a starting point for program development in other large freshwater lakes. Received January 16, 2015; accepted October 8, 2015

An Assessment of Nighttime Electrofishing in the Lower Wabash River

“…The differences were mainly from the higher CPUE of some species at night (i.e., Silver Carp, Longnose Gar, and River Carpsucker). Generally, nighttime electrofishing had higher catch rates relative to daytime electrofishing, which is consistent with our expectation and with previous research in both lotic and lentic systems (Paragamian 1989;Dumont and Dennis 1997;Fischer and Quist 2014;Ross et al 2016). Fish often move from deeper water to shoreline habitats at night to forage and avoid predators (McComish 1967;Craig 1977;Snedden et al 1999;Grabowski and Isley 2006;Straight et al 2015), increasing their capture in nighttime collections.…”

“…Both nighttime and daytime electrofishing are commonly used to sample fish in lentic systems throughout the United States, although nighttime electrofishing is often thought to be the most efficient (Witt and Campbell 1959;Sanderson 1960;Kirkland 1965;Dumont and Dennis 1997;Cross 2000, 2004;Ross et al 2016;Blackwell et al 2017). In the Midwest, nighttime electrofishing is commonly used in lakes when targeting certain species such as Largemouth Bass Micropterus salmoides, Bluegill Lepomis macrochirus, Walleye Sander vitreus, and Gizzard Shad Dorosoma cepedianum (Dumont and Dennis 1997;Mclnerny and Cross 2000).…”

Mark–recapture surveys affect nest site fidelity but not reproductive timing of male Smallmouth Bass

“…For example, if the same stretch of shoreline is surveyed year after year (e.g., Ross et al. 2016; Ohio Department of Natural Resources–Division of Wildlife 2023), catch per unit effort may be underestimated if individuals that are caught in the electrofishing survey subsequently avoid this area. If this is the case, randomly selecting sites to survey each year may be a more effective approach (as recommended by Miranda and Boxrucker 2009).…”

“…Any aversion to returning to a location where a male was captured via electrofishing could have implications for standardized spring surveys in large systems where surveying the entire shoreline is not feasible. For example, if the same stretch of shoreline is surveyed year after year (e.g., Ross et al 2016; Ohio Department of Natural Resources-Division of Wildlife 2023), catch per unit effort may be underestimated if individuals that are caught in the electrofishing survey subsequently avoid this area. If this is the case, randomly selecting sites to survey each year may be a more effective approach (as recommended by Miranda and Boxrucker 2009).…”

Improving Salmonid Monitoring by Nocturnal Counting in Rivers

“…However, Thurow and Schill (1996) found no diel differences in estimated density of Bull Trout Salvelinus confluentus parr when comparing drift diving at day and night. Similarly, electrofishing of salmonids is regularly done in daylight, although studies of nonsalmonid fish species have found electrofishing at night to yield higher estimates of both species diversity and fish densities in lotic (Paragamian 1989;Sanders 1992;Copp 2010;Graynoth et al 2012) and lentic habitats (Dumont and Dennis 1997;Pierce et al 2001;Schoenebeck et al 2005;Ross et al 2016;Blackwell et al 2017). Saunders et al (2011) demonstrated that the density of three trout species could be accurately estimated by nighttime electrofishing, but studies comparing night and daytime sampling for salmonids are lacking.…”