friend,foe-invasivespecies

Friend, Foe, Wonder, Peril

Invasive species are all of these.

A FEW YEARS AGO, I interviewed a 92-year-old Haida elder about the effects of introduced Sitka black-tailed deer on the ecosystems of Haida Gwaii. Something he said struck me: “I look at deer the same way as white man and what they’ve done to us.” This comment points to a serious limitation in our usual perception of invasive species as a problem in themselves, rather than a symptom – a riffle within a torrent of global change brought about by our species.

A FEW YEARS AGO, I interviewed a 92-year-old Haida elder about the effects of introduced Sitka black-tailed deer on the ecosystems of Haida Gwaii. Something he said struck me: “I look at deer the same way as white man and what they’ve done to us.” This comment points to a serious limitation in our usual perception of invasive species as a problem in themselves, rather than a symptom – a riffle within a torrent of global change brought about by our species.

We currently face diverse environmental consequences of how we have chosen to live on our home planet – from global warming and habitat loss to increasing nitrogen deposition and plummeting water tables. In the context of this large-scale change, invasive species are a convenient focus for activity. It’s relatively easy to feel you can do something about them – you simply reach down and uproot a plant or cull an unwanted mammal. Yet the fact remains that even if we could eliminate these species, much greater problems would remain and inexorable change would continue.

I may come across as pessimistic, even apathetic. I’m not. Instead, I see invasive species in two quite different – yet defensible – ways.

On the one hand, as a naturalist, I recognize that invasive species can be pernicious. These new plants and animals from far-away lands are taking over. They’ve driving out some of the species I have grown to know and love.

On the other hand, I can view these changes with greater acceptance. Species come and go. They always have. Some we like; some we don’t. Who made us the kings and queens of creation?

Here, I realize that my desire for one particular species over another has been partly learned – it’s even nostalgic. Many species are being lost; yes, that’s sad. But blaming invasive species for these changes is misplaced.

I’m not sure I’ll ever choose between these extreme views, for the in-between is much richer and more challenging. A vignette helps to explain what I mean. I grew up in Southern Ontario’s “banana belt,” alongside numerous rare and restricted Carolinian species, including blue ash, Kentucky coffee-tree, Eastern prickly pear cactus and swamp rose-mallow. It was a fragmented landscape, but my explorations were idyllic since I could walk untrammeled along hedgerows from one woodlot to another. As you can imagine, much has since changed, causing some native species to decline. Invasive species, however, are far from my biggest concern. Instead, it is something much less ominous, much more mundane.

Consider the 10-kilometre route my father and I run along the country roads. When we began, 27 years ago, we passed 10 homes. Now, 41 mailboxes mark our course and 13 of the new homes have been built in woodlots. Recently, the neighbouring farmer subdivided his forest, a focal point of my rambling, into three estate lots. Almost everywhere the story is the same: Yes, we have invasive species, but we have something else too: Human habits are just as much to blame.

I continue this childhood story with another worrying trend. I have fond memories of a class trip to Point Pelee National Park where the naturalists did an excellent job of showing us around and teaching us about the organisms that lived there. It was a magical day. Now, I worry that litanies against invasive species are replacing these wondrous experiences. Instead of learning to delight in nature, students learn what is wrong with it. I suspect they’ll be less likely to want to return.

It is possible to go too far here. I have no wish to be a defender of invasive species or to have developers adapt my arguments to defend their destruction of existing habitats, or to avoid expensive restoration. Even so, I feel that the way we typically conceptualize invasive species is too habitual. We need to be more aware of its shadow side. We need to face the hard questions about our place in nature and our role in the spread of these species. We need to become more intimate with invasive species.

With a little more intimacy, we’d hear strains of the same old humanist tune in our approach to invasive species. We may feel good about ourselves by pulling a few non-native plants out of a wetland or eradicating rats from an island, yet many of these species are clearly here to stay. Realistic projections based on the ongoing expansion of global trade further suggest that new exotic species will continue to arrive. With ongoing global climatic change, the distinction between mere “exotic” species and more problematic “invasive” ones may become less and less useful, but we still imagine ourselves controlling them. David Ehrenfeld called this belief, that we can put things back in order with assiduousness, greater scientific knowledge and technological know how, the “arrogance of humanism.”

We hold onto this belief, I suspect, because we like to think we have created a nice, tidy, managed world. We do what it takes to remove species we don’t want. For example, in many areas we’ve extinguished most of the original landscape and replaced it with invasive agricultural species. Now we eradicate weeds from these places. We apply a similar managerial ethos to reduce the economic disruption caused by invasive species elsewhere.

One reason we have invasive species, however, is that we’re cutting environmental corners to reduce economic costs and inconvenience elsewhere. How many of us have stopped driving our cars or travelling abroad to prevent the spread of invasive species? How many of us clean our boots after forays in foreign lands? How many of us buy food and other products from afar? How many of us import exotic plants for our gardens? We want the wheat without the chaff, counting on our ingenuity to set things straight.

This managerial ethos extends to our concerns about the effects of invasive species on biodiversity itself. We denounce foresters for thinking of forests as mere board-feet and fishers for thinking of fish as mere kilos for Captain High Liner, but we have ourselves reduced life to a particular and limited vision of diversity, one focusing on biotic communities as mere repositories of native species.

We have set aside certain areas as “natural,” as “parks” and “wilderness” that we especially wish to preserve from the impacts of “non-native” species. These parks are meant to be orderly and to provide a particular nature for our benefit and for our use. Here we have nature-without-humans, a product for the consumption of generally wealthy, well-educated people. The rest is nature-with-humans, which those same people tend to eschew.

As conservationists, we need to reflect upon whether we truly want to promote managerial enmity towards the natural world. We have made an enemy of invasive species to justify controlling and subjugating them; they have been reduced to an “other” rather than an element of biodiversity that we care about. Yet many who oppose these species only recognize the few non-native species they’ve been taught – and taught to dislike – rather than having a deeper

Brendon Larson, a professor in the Department of Environment and Resource Studies at the University of Waterloo, expects to ruffle some feathers with his unconventional view on invasive species. His final lines are offered with apologies to Pablo Neruda’s Book of Questions.