Extinction cascades partially estimate herbivore losses in a complete Lepidoptera-plant food web

University of California-Davis, Department of Entomology, 1 Shields Avenue, Davis, California 95616, USA.
Ecology (Impact Factor: 4.66). 08/2013; 94(8):1785-94. DOI: 10.1890/12-1075.1
Source: PubMed


The loss of species from an ecological community can have cascading effects leading to the extinction of other species. Specialist herbivores are highly diverse and may be particularly susceptible to extinction due to host plant loss. We used a bipartite food web of 900 Lepidoptera (butterfly and moth) herbivores and 2403 plant species from Central Europe to simulate the cascading effect of plant extinctions on Lepidoptera extinctions. Realistic extinction sequences of plants, incorporating red-list status, range size, and native status, altered subsequent Lepidoptera extinctions. We compared simulated Lepidoptera extinctions to the number of actual regional Lepidoptera extinctions and found that all predicted scenarios underestimated total observed extinctions but accurately predicted observed extinctions attributed to host loss (n = 8, 14%). Likely, many regional Lepidoptera extinctions occurred for reasons other than loss of host plant alone, such as climate change and habitat loss. Ecological networks can be useful in assessing a component of extinction risk to herbivores based on host loss, but further factors may be equally important.

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Available from: Florian Altermatt, Jan 21, 2015
    • "As such, there is considerable interest in developing predictive methods to anticipate the trophic interactions that might develop between introduced and native species before the introduction actually happens (NAS 2002, Briese 2003, Gilbert et al. 2012, Pearse and Altermatt 2013b, Pearse et al. 2013). There have been several efforts to conceptually define the factors that cause some novel trophic interactions to form while others do not (Verhoeven et al. 2009, Harvey et al. 2010, Sih et al. 2010, Pearse et al. 2013). In each of these cases, the likelihood of a novel interaction can be described by the host breadth of the exploiter, the exploitability (or, conversely, defense) of the exploited organism, and the match between those organisms. "
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