Journal Article

diversity of juvenile salmonids does not affect their competitive impact on a native galaxiid

Gajardo, Gonzalo, Thailly, Anne-Flore, Terreau, Alexandre, de Leaniz, Carlos Garcia, Stephenson, Jessica, Young, Kyle A

2009

Overview

We used an invaded stream fish community in southern Chile to experimentally test whether the diversity of exotic species affects their competitive impact on a native species. In artificial enclosures an established invasive, rainbow trout, Oncorhynchus mykiss, and a potential invader, Atlantic salmon, Salmo salar, reduced the growth rate of native peladilla, Aplochiton zebra, by the same amount. In enclosures with both exotic salmonids, the growth rates of all three species were the same as in single exotic treatments. While neither species identity nor diversity appeared to affect competitive interactions in this experiment, the impact of salmonid diversity may vary with the type of interspecific interaction and/or the species identity of the exotics. Our experiment links two prominent concepts in invasion biology by testing whether the result of invasional meltdown, an increase in the diversity of exotic species, affects their impact through interspecific competition, the mechanism invoked by the biotic resistance hypothesis.

• Publisher: Dordrecht : Springer Netherlands,Springer Netherlands,Springer Nature B.V
• Subject: animal growth / Animal populations / Aplochiton zebra / Aquatic ecology / Biodiversity / Biomedical and Life Sciences / Chile / Developmental Biology / ecological invasion / Ecology / Fish / Freshwater & Marine Ecology / Galaxiidae / Habitats / Indigenous species / interspecific competition / Introduced species / Invasive fish / invasive species / juveniles / Life Sciences / Nonnative species / Oncorhynchus mykiss / Original Paper / Plant Sciences / Salmo salar / Salmon / Salmoniformes / Species diversity / streams / trout