A comprehensive global study of invasive species characteristics in aquatic environments
A Southampton PhD student, based at the Marine Biological Association (MBA) in Plymouth, has published a comprehensive analysis investigating traits that may promote successful establishment and spread of nonindigenous species in aquatic environments on a global scale.
Ella McKnight has drawn together findings from global scientific papers to explore the reasons why some nonindigenous species being introduced into marine and freshwater environments do better than native species.
The innovative research was based on a meta-analysis – a statistical procedure for combining data from multiples scientific studies and papers – and studies the traits of plants and animals living in aquatic ecosystems around the world.
The paper Global meta-analysis of native and nonindigenous trophic traits in aquatic ecosystems has been published by Global Change Biology – a prestigious international journal that promotes the understanding of the interface between all aspects of current environmental change affecting a substantial part of the globe and biological systems.
The research, carried out in collaboration with Ella’s PhD supervisor Dr Mark Rius and colleagues at the University of Girona, in Spain, considered a total of 342 data points from 74 peer-review papers.
Historically studies have focused on invasive species in terrestrial environments but very few have investigated aquatic environments. The research investigated a range of marine and freshwater plants and animals including algal species, fish, invertebrates and amphipods, and particularly focused on their growth, behaviour and physiology.
Ella said: “Previously the focus has always been on terrestrial species and there has been a general lack of meta-analayses on aquatic ecosystems. Aquatic environments are different to terrestrial environments because there is the potential for massive swarms of species to be moved at the same time, carried by the ballast waters of large vessels along shipping routes.
“Our study provides one of the first comprehensive meta-analysis of trophic trait differences between nonindigenous and native species, covering a wide range of aquatic taxa and scenarios.
“We wanted to determine whether introduced species may have the potential to establish, spread and possibly cause extinction to native species. Our research identified a set of trophic traits – specifically growth, consumption and behaviour – that facilitate the colonisation and establishment of aquatic nonindigenous species and are key to understanding and predicting future species invasions.”
The analysis discovered a bias towards studies conducted in temperate climates and recommended that more studies be carried out in tropical climates and at the poles.
“I am delighted to have my paper published in such a prestigious journal, more so because I have only just begun my PhD studies,” said Ella.
Marc added: “This project would not have been possible without our close collaboration with leading freshwater ecologists at the University of Girona. This study used a cross-ecosystem approach that required expertise on both freshwater and marine ecosystems.”
Ella is a Southampton Partnership for Innovative Training of Future Investigators Researching the Environment (SPITFIRE) student. SPITFIRE is a Natural Environment Research Council (NERC) Doctoral Training Partnership creating an innovative multidisciplinary experience for the effective training of future leaders in environmental science, engineering, technology development, business and policy.