The facilitation of the native bluegill sunfish by the invasive bighead carp. (17th July 2017)

• Record Type: Journal Article
• Authors: Collins, Scott F.; Nelson, Kirsten A.; DeBoom, Corey S.; Wahl, David H.
• Is Part Of: Freshwater biology. Volume 62:Number 9(2017)
• Page Start: 1645
• Page End: 1654
• Publication Date: 2017-07-17
• Subjects: Asian carp -- Centrarchidae -- facilitation -- indirect effect -- invasive species; Freshwater biology -- Periodicals; Biologie d'eau douce -- Périodiques; 577.605
• DOI: 10.1111/fwb.12976
• Languages: English
• ISSNs: 0046-5070

Abstract

Abstract: Communities of organisms are shaped by a complex suite of positive and negative species interactions. Ecological phenomena like biological invasions typically evoke notions of negative effects on native communities. Yet, negative effects within specific food‐web components can also have positive feedbacks that manifest elsewhere within the food web. We designed an experiment to evaluate the direct and indirect effects of invasive bighead carp ( Hypophthalmichthys nobilis : Cyprinidae) on planktonic and benthic invertebrates and the growth and survival of juvenile bluegill sunfish ( Lepomis macrochirus : Centrarchidae). Our experiment indicated that the presence of bighead carp indirectly facilitated bluegill growth and survival. The underlying processes driving predator–predator facilitation stemmed from a combination of indirect interactions occurring through invertebrates in planktonic and vegetated habitats. Individual bluegill consumed more cladocerans and predatory macroinvertebrates in the presence of bighead carp. The presence of bighead carp appears to have indirectly influenced interactions among cladocerans, invertebrate predators, and bluegill. Understanding the cumulative direct and indirect effects of bigheaded carp on aquatic ecosystems requires the documentation of both negative and positive effects. Although one taxon benefitted from the presence of an invader, our findings demonstrate that this response occurred because bigheaded carp caused imbalances within the food web. We urge that future studies consider a priori how positive and negative interspecific interactions shape the structure of food webs.