Effects of Round Goby on the Benthic Invertebrate Community and on Diets and Growth of Yellow Perch and White Perch in Oneida Lake, New York

Abstract

Food web changes from the introduction of nonnative species can be complex, with sometimes unexpected effects or little effect due to food web interactions. Invasive Round Goby Neogobius melanostomus became common in samples in Oneida Lake, New York, by 2014. Data from a long‐term monitoring program allowed us to document the Round Goby expansion through time. Using shoreline seine, fyke net, bottom trawl, and video surveys, we estimated that Round Goby density reached over 25,000 fish/ha 6 years after detection and subsequently varied between 4,110 and 26,565 fish/ha. Concurrent benthic invertebrate sampling and long‐term fish diet sampling allowed us to assess the impacts of Round Goby on densities of several benthic invertebrate taxa and on invertebrate consumption by fish. Significant decreases in density after Round Goby arrival were found for amphipods (Amphipoda), caddisflies (Trichoptera), snails (Gastropoda), and dreissenid mussels Dreissena spp. Invertebrate densities after Round Goby arrival ranged from 19% to 48% of densities in the pre‐Round Goby period. For amphipods, snails, and, in some cases, caddisflies and chironomids (Chironomidae), frequency of occurrence in the diets of Yellow Perch Perca flavescens and White Perch Morone americana was lower after Round Goby became established. The decreased consumption of these invertebrates did not lead to decreases in fish growth; growth increased for some age‐classes of Yellow Perch and all age‐classes of White Perch. Despite potential Round Goby predation, densities of burrowing mayflies Hexagenia spp. expanded during this time and likely helped to offset reductions in consumption of other invertebrates by Yellow Perch and White Perch, as did consumption of Round Goby. Long‐term monitoring shows that Round Goby decreased the density of several benthic invertebrate species and decreased the consumption of these invertebrates by fish, but the effect on growth of Yellow Perch and White Perch was offset by consumption of Round Goby and burrowing mayflies.

The effects of Bythotrephes longimanus invasion on diets and growth of age‐0 yellow perch in Oneida Lake, New York

“…Thus, yearling and older yellow perch fed on this new prey item shortly after its arrival to the lake as documented elsewhere (Bur & Klarer, 1991). Additionally, we did not observe any decline in adult yellow perch growth rates (recently analysed in Brooking et al, 2022). Larger yellow perch feed on a variety of prey items including zooplankton, benthic invertebrates and fish (Mayer et al, 2001; Mills & Forney, 1981) and changes in zooplankton communities are not expected to have a major effect on growth rates of adult yellow perch.…”

Environmental abundances of the non‐native round gobyNeogobius melanostomusinfluence feeding of native fish predators

“…Together with the lower prey richness for predators feeding most on N. melanostomus , this suggests that N. melanostomus is replacing rather than supplementing native prey when it is abundant in the environment, at least for G. morhua and E. lucius . Nonetheless, on a longer timescale, N. melanostomus may act as a supplemental dietary resource, as N. melanostomus environmental abundances can be expected to fluctuate between seasons (Behrens et al ., 2022; Brauer et al ., 2020) and years (Brooking et al ., 2022; this study). The dominance of N. melanostomus as prey for G. morhua and E. lucius in KK seen in this study could indicate potential for predator control of N. melanostomus when abundant, but the influence of predator regulation on N. melanostomus population dynamics in the Baltic Sea remains a topic for future studies.…”

Larval cisco and lake whitefish exhibit high distributional overlap within nursery areas

“…Lake whitefish juveniles and adults rely on benthic macroinvertebrate prey, but the replacement of their preferred Diporeia prey with energy‐poor Dreissena mussels (Burlakova et al, 2022) has dramatically altered their foraging ecology, inducing growth and recruitment declines for populations across the Great Lakes (Fera et al, 2015; Mohr & Nalepa, 2005; Rennie et al, 2012; Trumpickas et al, 2022). Further, the invasive round goby ( Neogobius melanostomus ) has caused declines in benthic invertebrate assemblages, as observed in Lake Michigan (Kuhns & Berg, 1999), Lake Erie (Barton et al, 2005) and Oneida Lake (Brooking et al, 2022), which should impact lake whitefish more than cisco. Additional anthropogenic stressors on adults (e.g.…”