From the June 2013 Conservationist
When it comes to certain wildlife, some disturbance can be a good thing
By Eli J. Knapp
My ornithology class was quickly taking on the feel of a forced march. Energy levels were flagging, black flies were buzzing, and the swamp's morning bird symphony had reached an intermission. But being an overly optimistic ornithology professor, I desperately wanted my students to see a northern goshawk, the fierce and elusive bird of our northern forests.
I turned to my sun-baked audience, hoping to rouse them for one last pursuit. "We'll leave the swamp and head into this grove of evergreens!" I yelled, hoping my voice would carry to those in the back. "But first we need to switch disciplines, from ornithology into conservation biology. Who can tell me why we need large expanses of intact forest?" I asked.
Fortunately, at least one student was still lucid. "Because that's the only place that some species will use!" a flannel-shirted guy named Joe hollered from the back.
"Exactly," I said, flashing Joe an appreciative smile. "The goshawk is a case in point."
The canopy closed overhead as we marched into the evergreens. Last year, I had staked out a place that goshawks had nested in. But now, as we marched, I noticed sunlight coming from my desired destination. What had happened to my forest? (Like many who frequent public lands, I felt informal ownership of this parcel.)
Moments later, to my dismay, the mystery solved itself. The previous year's goshawk grounds had been transformed into a patch clear-cut with the ground littered with fallen tree tops and bramble. The forest surrounding the clear-cut was still intact, though, as if aliens had flown over and simply removed a perfectly rectangular patch for further study.
The students read my expression like a book. "I guess we won't be finding any goshawks, will we?" a girl asked.
mourning warbler (Photo: Jeff Nadler)
"Not today," I responded, feebly trying to mask my despair. I paused a moment to collect myself. But I couldn't. My emotions bubbled up and I stood on my soapbox made possible by a nearby stump. I knew better than to intentionally interject my own biases into my class. But I was too wounded to refrain. "This," I exclaimed, "is what happens when you clear-cut before consulting with ornithologists, ecologists, and conservation biologists! Yeah, it'll grow back. But goshawks don't tolerate ripped up forests. They need their home intact. Maybe they've found suitable nesting nearby. But I doubt it. Look at this everybody and remember it
I paused, hoping to impregnate the moment with meaning and inspire the next generation of environmentalists. Stunned by my outburst, nobody said a word. But the silence was suddenly broken by an unmistakable warble. At first it was faint. I cupped my ears. Like an approaching ambulance, the beautiful string of notes steadily increased.
"What is that?" Joe asked, scanning the vegetation with his binoculars.
"It's a warbler," I responded, trying to hide my uncertainty.
A planned timber harvest may appear
unsightly at first (see photo at top of
page), but the area greens up
quickly with lush vegetation. (Photo:
I needed time to flip through my dusty mental audio database and retrieve this species that I hadn't heard, or seen, in years. But Joe was persistent. For him and my other students, professors that readily profess philosophy from freshly hacked tree stumps had better be able to profess the name of a dainty little bird warbling nearby.
My dimly flickering light bulb finally blazed. "It's a mourning warbler!" I exclaimed.
I crashed through a tangle, absorbed a dozen blackberry thorns, and finally laid eyes on my quarry. Sure enough, a male mourning warbler was singing his springtime heart out from the top of a small sapling. "Do you all see it?!" I whisper-shouted back to my confused class.
A few heads nodded; others madly scanned the foliage. But before everyone saw it, the warbler dissolved back into the brush. Excited, I fought my way back to the class and dredged up my dormant mourning warbler facts.
"Now that is a fantastic bird!" I started. "It's never abundant because of its very specific habitat requirements. For the mourning warbler to flourish, it needs a disturbed area with thick underbrush. It needs a disturbance that's surrounded by mature forest. Essentially the mourning warbler needs storms or fire or loggers to disturb the forest to give it the right habitat to nest." In my excitement, I missed the obvious irony I'd dimwittedly created. But my students didn't.
"You mean it needs a clear-cut?" a girl named Brianna asked innocently, scribbling in her field notebook.
"So a clear-cut is good?" she pressed, her pen poised like a hummingbird inspecting a flower.
Several students were now taking notes. I paused again, knowing my words were being recorded as sacrosanct. I needed to choose them carefully.
I hesitated. "It's ultimately a question about values. Or trade-offs. Should we destroy habitat for the goshawk to create it for the warbler? Or exclude the warbler for the goshawk? What do you all think?" I asked. Although new at teaching, I'd quickly learned the quasi-duplicitous art of asking a question to mask my own momentary ignorance. "We'll discuss that more this afternoon," I said. "In the meantime, we best get going."
Since my students knew the route, I intentionally took the rear to avoid conversation. I needed to think. I had stumbled into an inadvertent double-standard. Here I was the professor, yet I was the one learning the lesson.
The author in the classroom.
I hold an advanced degree in ecology. Yet my discipline, like so many others, frequently breeches the walls of philosophy. I often revel in it, in fact, promoting any cross- and multidisciplinary endeavors that come my way. But it's risky, too. Expertise can only go so far. So when I do storm another colleague's castle, how far can-or should-I go? So much, I'm learning, rides on this question; the invaluable academic lives of my students, and the actual lives of goshawks and warblers, among myriad other creatures.
By the time we piled in the vans, I still had no answers to the goshawk-versus-warbler question. Nor about logging. The answers are undeniably complex. But I had arrived at a simpler truth, previously obscured by the tangle of questions: When I'm teaching-or preaching-about the philosophy of nature, humility must be lesson number one. As the mourning warbler reminded me with its clarion call, answers to nature's riddles are rarely clear-cut.
Eli J. Knapp is a professor of biology at Houghton College.
Photo: Jim Clayton