When marine species are redistributed by human transport systems, such as ballast water, the success of establishment and magnitude of ecological impact depend on a variety of factors. Temperature is a fundamental driver of physiological performance of species, however, its role in shaping impacts of invasive marine species remains largely unexplored.
In this study, researchers set out to quantify the impact of invasive species in marine ecosystems, exploring how these may relate to differences in temperature. The authors identified 50 species with recorded ecological impact, and then used GBIF-mediated data to assess the ranges of the species and characterize their realized thermal niches.
Their analysis showed that most invasions occurred poleward of the cool edge of a species' range with an overall mean shift of 6.8 degrees latitude. Thermal midpoints at these locations were on average 1.2 degrees cooler than those of the native ranges.
The ecological effect of invasions on abundance of native taxa was most severe at sites 2.2 degrees cooler than the origin of the invader, with decreasing effect toward higher and lower differences in temperature.
The study concludes that seemingly harmless species established outside their native ranges need to be monitored as they may develop larger impacts with future warming oceans.