Native invaders divide loyalties

7 09 2012

California sea lion at Bonneville fish ladder. Credit: U.S. National Oceanic and Atmospheric Administration

As if to mimic the weirder and weirder weather human-caused climate disruption is cooking up for us, related science stories seem to come in floods and droughts. Yes, research trends become fashionable too (imagine a science fashion show? – but I digress…).

Only yesterday, the ABC published an opinion piece on the controversies surrounding which species we call ‘native’ and ‘invasive’ (based on a recent paper published in Global Ecology and Biogeography), and in June this year, Salvador Herrando-Pérez wrote a great little article on the topic entitled “The invader’s double edge“.

Then today, I received a request to publish a guest post here on ConservationBytes.com from Lauren Kuehne, a research scientist in Julian Olden‘s lab at the University of Washington in Seattle. The topic? Why, the controversies surrounding invasive species, of course! Lauren’s following article demonstrates yet again that it’s not that simple.

A drawback to the attention garnered by high-profile invasive species is the tendency to infer that every non-native species is bad news, the inverse assumption being that all native species must be ‘good’. While this storyline works well for Hollywood films and faerie tales, in ecology the truth is rarely that simple. A new review article in the September issue of Frontiers in Ecology and the Environment, describes the challenges and heartbreaks when native species run amok in the sense of having negative ecological impacts we typically associate with non-native species. Examples in the paper range from unchecked expansions of juniper trees in sagebrush ecosystems with wildfire suppression, to overgrazing by elk (wapiti) released from predation following the removal of wolves and mountain lions. Read the rest of this entry »