Dispersal and emerging ecological impacts of Ponto-Caspian species in the Laurentian Great Lakes

Abstract

We describe, explain, and "predict" dispersal and ecosystem impacts of six Ponto-Caspian endemic species that recently invaded the Great Lakes via ballast water. The zebra mussel, Dreissena polymorpha, and quagga mussel, Dreissena bugensis, continue to colonize hard and soft substrates of the Great Lakes and are changing ecosystem function through mechanisms of ecosystem engineering (increased water clarity and reef building), fouling native mussels, high particle filtration rate with selective rejection of colonial cyanobacteria in pseudofeces, alteration of nutrient ratios, and facilitation of the rapid spread of their Ponto-Caspian associates, the benthic amphipod Echinogammarus ischnus and the round goby, Neogobius melanostomus, which feeds on zebra mussels. The tubenose goby,Proterorhinus marmoratus, which does not feed on zebra mussels, has not spread rapidly. Impacts of these benthic invaders vary with site: in some shallow areas, habitat changes and the Dreissena [Formula: see text] round goby [Formula: see text] piscivore food chain have improved conditions for certain native game fishes and waterfowl; in offshore waters, Dreissena is competing for settling algae with the native amphipod Diporeia spp., which are disappearing to the detriment of the native deep-water fish community. The predatory cladoceran Cercopagis pengoi may compete with small fishes for zooplankton and increase food-chain length.

Substrate preferences of coexisting invasive amphipods, Dikerogammarus villosus and Dikerogammarus haemobaphes, under field and laboratory conditions

“…The Ponto-Caspian region represents one of the most significant sources of invasive taxa within western Europe (Müller et al 2002;Gallardo and Aldridge 2013a) and North-America (Ricciardi and MacIsaac 2000;Vanderploeg et al 2002). Ponto-Caspian invaders have been particularly successful in expanding beyond their native range associated with their wide environmental tolerances to water quality, thermal regime variability and habitat modifications (Havel et al 2005; Gallardo and Aldridge 2013a; ).…”

Sensitivity of native and non-native mollusc species to changing river water temperature and salinity

“…Rising water temperatures may lead to replacement of coldwater mollusc species by more thermophilic ones (Daufresne et al 2004), but the mechanisms that may explain this shift are not yet understood. As molluscs constitute a large share of the group of macroinvertebrate invaders (Karatayev et al 2009;Leuven et al 2009) and invasive, fouling molluscs have serious economic and ecological impacts (Connelly et al 2007;Pimentel et al 2005;Strayer 2010;Vanderploeg et al 2002), there is a particular need for knowledge on physiological tolerances of these species. Knowledge on facilitating or limiting factors for the establishment of non-native mollusc species could be helpful to predict future species replacements and to derive management options for invasive species.…”

Assessment of fish size on shelter choice and intraspecific interactions by round gobies Neogobius melanostomus

“…Because round gobies are abundant (up to 90 fish m )2 ) in rocky habitats (Ray & Corkum 2001, Johnson et al 2005 and both juvenile and adult gobies feed on eggs of lake trout, Salvelinus namaycush (Chotkowski & Marsden 1999), lake sturgeon, Acipenser fulvescens (Nichols et al 2003), and smallmouth bass, Micropterus dolomieu (Steinhart et al 2004), round gobies may reduce the recruitment of native fishes (Vanderploeg et al 2002). Round gobies also may alter ecological function by transferring energy and contaminants from the benthos to higher trophic levels and so represent a health concern (Morrison et al 2000).…”