Biological Invaders – Ecology
Music; Ambience: dawn chorus, Ventana Wilderness
This week, we’ve been hearing about invasive species – plants and animals that move into foreign ecosystems and cause serious environmental damage. Well, one guess as to which is the most invasive species of all. I’m Jim Metzner, and this is the Pulse of the Planet.
Lonsdale: In the strict definition of the term invasive species, which means a species that’s moved outside of its range of origin and is starting to expand out of control, human beings are the great invasive species.
Ecologist Mark Lonsdale specializes in the study of invasive species. He says that not only do humans move other species to new locations, by intent or accident, but we also make it easier by our actions for a new species to take hold.
Lonsdale: What they’re doing is opening up and making way for other invasive species to follow. So as we move through the landscape, clearing vegetation, using our fertilizers, opening up vegetation for agriculture, invasive species follow in our wake. One thing that has emerged is that damaged ecosystems do tend to be very susceptible to invasions. You create gaps and species will come in and colonize those gaps.
And there are very practical reasons to be concerned about invasive species.
Lonsdale: In Australia, about 20 percent of the value of our grain crop is expended on weed control – and these weeds are all invasive species. And for America there’s a tremendous cost to you as well, which has been recognized by successive governments and by a series of big studies. They really are not just a biodiversity impact but also an economic impact.
To hear about our new CD, please visit pulseplanet.com. Pulse of the Planet is made possible by the National Science Foundation. I’m Jim Metzner.