title: Non-native marine invertebrates are more tolerant towards environmental stress than taxonomically related native species: results from a globally replicated study.
abstract: To predict the risk associated with future introductions, ecologists seek to identify traits that determine the invasiveness of species. Among numerous designated characteristics, tolerance towards environmental stress is one of the most favored. However, there is little empirical support for the assumption that non-native species generally cope better with temporarily unfavorable conditions than native species. To test this concept, we ran five pairwise comparisons between native and non-native marine invertebrates at temperate, subtropical, and tropical sites. We included (natives named first) six bivalves: Brachidontes exustus and Perna viridis, P. perna and Isognomon bicolor, Saccostrea glomerata and Crassostrea gigas, two ascidians: Diplosoma listerianum and Didemnum vexillum as well as two crustaceans: Gammarus zaddachi and G. tigrinus. We simulated acute fluctuations in salinity, oxygen concentration, and temperature, while we measured respiration and survival rates. Under stressful conditions, non-native species consistently showed less pronounced deviations from their normal respiratory performance than their native counterparts. We suggest that this indicates that they have a wider tolerance range. Furthermore, they also revealed higher survival rates under stress. Thus, stress tolerance seems to be a property of successful invaders and could therefore be a useful criterion for screening profiles and risk assessment protocols.
authors.affiliation: Marine Ecology Department, Leibniz-Institut für Meereswissenschaften an der Christian-Albrechts Universität Kiel, Düsternbrooker Weg 20, Kiel, Germany. mlenz@ifm-geomar.de
authors.forename: Mark
authors.initials: M
authors.lastname: Lenz
authors.forename: Bernardo A P
authors.initials: BA
authors.lastname: da Gama
authors.forename: Nadine V
authors.initials: NV
authors.lastname: Gerner
authors.forename: Judith
authors.initials: J
authors.lastname: Gobin
authors.forename: Frederike
authors.initials: F
authors.lastname: Gröner
authors.forename: Anil
authors.initials: A
authors.lastname: Harry
authors.forename: Stuart R
authors.initials: SR
authors.lastname: Jenkins
authors.forename: Patrik
authors.initials: P
authors.lastname: Kraufvelin
authors.forename: Corinna
authors.initials: C
authors.lastname: Mummelthei
authors.forename: Jörg
authors.initials: J
authors.lastname: Sareyka
authors.forename: Eduardo A
authors.initials: EA
authors.lastname: Xavier
authors.forename: Martin
authors.initials: M
authors.lastname: Wahl
mesh_terms: D000064:Acclimatization; D000818:Animals; D049872:Bivalvia / Q000145:classification / Q000502:physiology*; D003445:Crustacea / Q000145:classification / Q000502:physiology*; D017753:Ecosystem; D058865:Introduced Species; D010101:Oxygen Consumption; D011157:Population Dynamics; D054712:Salinity; D013312:Stress, Physiological; D013696:Temperature; D014561:Urochordata / Q000145:classification / Q000502:physiology*