Indirect effects of invasive species removal devastate World Heritage Island

• Published in: Journal of Applied Ecology
• Main Authors: Bergstrom, DM, Lucieer, A, Kiefer, K, Wasley, J, Belbin, L, Pedersen, TK, Chown, SL
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley-Blackwell Publishing Ltd 2009
• Subjects: Environmental Sciences; Ecological Applications; Invasive Species Ecology; Antarctic; Antarc*
• Online Access: https://doi.org/10.1111/j.1365-2664.2008.01601.x; http://ecite.utas.edu.au/54573

Summary1.Owing to the detrimental impacts of invasive alien species, their control is often a priority forconservation management. Whereas the potential for unforeseen consequences of management isrecognized, their associated complexity and costs are less widely appreciated.2.We demonstrate that theoretically plausible trophic cascades associated with invasive speciesremoval not only take place in reality, but can also result in rapid and drastic landscape-widechanges to ecosystems.3.Using a combination of population data from of an invasive herbivore, plot-scale vegetationanalyses, and satellite imagery, we show how a management intervention to eradicate a mesopredatorhas inadvertently and rapidly precipitated landscape-wide change on sub-Antarctic Macquarie Island.This happened despite the eradication being positioned within an integrated pest managementframework. Following eradication of catsFelis catusin 2001, rabbitOryctolagus cuniculusnumbersincreased substantially although a control action was in place (Myxomavirus), resulting in island-wideecosystem effects.4.Synthesis and applications. Our results highlight an important lesson for conservation agenciesworking to eradicate invasive species globally; that is, risk assessment of management interventionsmust explicitly consider and plan for their indirect effects, or face substantial subsequent costs. OnMacquarie Island, the cost of further conservation action will exceed AU$24 million.