Forecasting impact of existing and emerging invasive gobiids under temperature change using comparative functional responses

Abstract

In this study, we have performed a large-scale assessment on the native distribution range of the marine non-indigenous species (NIS) found in at least one of the European Seas (Mediterranean, NE Atlantic Ocean, Black, Baltic Sea). As a basis, we have used the most updated pan-European NIS inventory, provided by the European Alien Species Information Network. All taxonomic groups have been considered for this analysis, taking into account established NIS in European Seas (824 taxa in total). The vast majority of the European marine NIS have their native distribution in the Western and Central Indo-Pacific, being mostly associated with introductions into the Mediterranean Sea through the Suez Canal. However, this overall pattern is heavily influenced by the fact that 76% of all NIS primary introductions in Europe have been reported first from the Mediterranean Sea. A more detailed analysis revealed various patterns of the dominating native distributions of the primarily introduced NIS in Europe, depending on the European marine subregions where they have been initially introduced and their associated pathways. There seems to be a general decrease in NIS introductions in Europe, especially when it comes to NIS with native distribution in the Temperate Northern Pacific, although this trend should be treated with caution. The information provided in the current study can be useful for tailored management of specific primary pathways per marine subregion, supporting prioritization efforts.

Prediction of ecological impact of two alien gobiids in habitat structures of differing complexity

“…Although the impact of Proterorhinus semilunaris has had little attention (Kocovsky et al 2011) compared with that of Neogobius melanostomus (Kornis et al 2012), Gebauer et al (2018) showed similar per capita impact of the species at 20°C. In predatory fish species, type II FR (i.e., inverse density-dependent predation) is a common foraging pattern, although variations in environment may produce shifts in FR types (Koski and Johnson 2002).…”

“…Similarly, Dubs and Corkum (1996) observed higher FR of Neogobius melanostomus compared with native mottled sculpin (Cottus bairdii). In a comparison of Neogobius melanostomus with Proterorhinus semilunaris, Gebauer et al (2018) found similar per capita ecological impact of both species towards pelagic prey. Both Neogobius melanostomus and Proterorhinus semilunaris are opportunistic feeders with diets consisting chiefly of benthic invertebrates, while their consumption of fish eggs and juveniles is generally low (French and Jude 2001;Vašek et al 2014).…”

“…Based on the studies of Laverty et al (2017) and Gebauer et al (2018), it can be assumed that both Neogobius melanostomus and Proterorhinus semilunaris outperform analogous native species Cottus gobio because of similar C max values of both aliens. We observed no interactions between predator species and habitat conditions for weight-specific C max .…”

“…Temperature and habitat structure can be considered the most important abiotic drivers influencing predator-prey interactions (Alexander et al 2012(Alexander et al , 2015Englund et al 2011;Vucic-Pestic et al 2011). Recent comparison of Neogobius melanostomus and Proterorhinus semilunaris preying on common carp (Cyprinus carpio) larvae revealed no difference in FR on sandy substrate at 20°C, suggesting similar impact of tested species during the cyprinid spawning season (Gebauer et al 2018). Cyprinids are often phytophilous or lithophilous species, and newly hatched larvae prefer habitats characterized by submerged vegetation or gravel (King 2004).…”

Inter‐specific differences in invader and native fish functional responses illustrate neutral effects on prey but superior invader competitive ability

“…The relationships between consumer resource uptake and resource densities result in three FR types : linear Type I, hyperbolic Type II, and sigmoidal Type III (Holling, ; Jeschke et al., ). Functional responses have been applied to various aspects of ecology (Abrams, ; Englund & Harms, ; Faria, Godoy, & Trinca, ; Feldman, ), such as assessing adaptive behaviours (Abrams, ) and how resource abundance influences the per capita effects of individual predators under a number of environmental variables such as temperature (Stephens & Krebs, ), but only more recently have comparative FR analyses been used to assess invasive species impacts on resources such as prey, whereby the impact of an invader is contrasted with functionally similar native and/or non‐native species (Dick et al., ; Gebauer, Veselý, Kouba, Buřič, & Drozd, ; Xu et al., ).…”