I live near the Long Island Sound, in a landscape overrun with invaders from all over the world. My wife spends her free time ripping out Japanese knotweed from our garden. The Connecticut salt marshes are overrun with invasive Phragmites reeds. Starlings descend on us like a hail storm. So I found it intriguing to discover some scientists who don’t consider invasive species to be all that big a deal compared to other effects we’re having on the environment, like habitat destruction and climate change. In today’s Science Times section of the New York Times, I have an article about some of their recent research, and their critics who think they’re missing the true dangers of invasives.
The article was not based merely on vented spleen. There have been a number of papers published on this issue in recent years. Here are a few…
Dov Sax and Steven Gaines, “Species Invasions and Extinctions: The Future of Native Biodiversity On Islands.” Proc Natl Acad Sci U S A. 2008 Aug 12;105 Suppl 1:11490-7. Epub 2008 Aug 11.
TJ Stohlgren et al, “The Myth of Plant Species Saturation.” Ecol Lett. 2008 Apr;11(4):313-22; discussion 322-6. Epub 2008 Jan 31.
Dov Sax et al, “Ecological and evolutionary insights from species invasions,” Trends Ecol Evol. 2007 Sep;22(9):465-71. Epub 2007 Jul 20.
Mark Vellend et al, “Effects of exotic species on evolutionary diversification.” Trends Ecol Evol. 2007 Sep;22(9):481-8. Epub 2007 Mar 7.
Anthony Ricciardi, “Are modern biological invasions an unprecedented form of global change?” Conserv Biol. 2007 Apr;21(2):329-36.
September 9th, 2008 at 9:40 am
Loved this mornings NYT article. It brought to mind something I’d read about the noted naturalist Loren Eisley who would, as he travelled around the world, often intentionally carry seeds from past locations for the expressed purpose of surreptitously introducing them as exotics when he felt it might add to the diversity of a place..or just “fit in”, “part of the process” and all that.
It’s always refreshing to read arguments counter to the wild hyperoble typical to the news media that feeds the alarmed, though only partially informed, reaction. Of course the alarmed reader/viewer is someone who’s likely buying newspapers or watching TV thus adding to the wealth of the publisher or broadcaster and encouraging them to do more of that kind of stuff.
I sure look forward to the day when we see the same kind of treatment to counter some of the wildest worst case scenarios described regarding our planet’s environment and its ability to withstand climatic shifts due to the principles of dynamic equilibrium, a concept evidently too turgid for the passionately involved.
Now, as for asteroid or cometary impact…there’s something we can rightfully worry about, and in my opinion, something we ought to soon. Cheers.
September 9th, 2008 at 1:22 pm
Quite frankly, doug l, I’m horrified by Loren Eisley’s behavior. He went beyond imposing an aesthetic interpretation, he was imposing an aesthetic reality. And given what we now know about what determines invasiveness, he likely had little clue what would “behave” in the new environment.
For many invasive species problems, hyperbole is simply not possible. Strawberry guava in Hawaii, Brazilian pepper in the Everglades, kudzu, Phragmites, melastomes in the tropical Pacific, water hyacinth… these plants and many others, as invasives, have the capacity to quickly and radically alter environments that are otherwise largely unthreatened. Invasive species are arguably the only destructive threat that truly protected areas face in today’s climate conditions.
I’m an academic who’s worked on invasive species in the past, and while we’ve spent a lot of time teasing apart the mechanisms that promote invasiveness, and still have a lot to learn, the immediate impact such species have can be evident to anybody simply by walking around affected vs. unaffected areas. “Green” does not always equal “good”.
September 14th, 2008 at 5:31 pm
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