Have conservation scientists become carried away, touting the ecological benefits of wolves where there are perhaps — dare I say it? — not as many as we believe there to be? Perhaps some people in the media, and even some in science, have gotten carried away with the ecological changes that wolves are actually capable of mediating, says globally-renowned wolf biologist L. David Mech in his most recent paper “Is science in danger of sanctifying the wolf?”
Ever since the reintroduction of gray wolves to Yellowstone National Park, and by extension the Northern Rocky Mountain ecoregion, the role of apex predators in regulating trophic cascades has been an issue of great debate. Among the first to publish a correlation between a return of aspen and willow recruitment to stands where they’d been long absent, at the same time that wolves were reintroduced, were a pair of researchers from Oregon State University, Ripple and Beschta. They promulgated an idea dubbed the ecology of fear which postulated that the presence of wolves caused a behavioral shift in elk, leading them to graze less often in open riparian corridors where they were more likely to be attacked by wolves. Their warier behavior, and shift in browsing pressure, led to a rebound in the aspen and willow growth. It’s become a familiar, almost calcified narrative, and one that many wildlife proponents have embraced (myself included).
But in his newest paper, Mech reviews the literature both supporting and refuting wolves as the mechanism of a behaviorally-modulated trophic cascade in Yellowstone. He asserts that other factors may be at play in stimulating the willows and aspen to regrow, and that they at least deserve more serious discussion. Mech seems to feel that some conservation scientists have become so myopically focused on wolves as the mechanism of ecological change that we tend to view as positive that they are unwilling or unable to look beyond wolves for alternative or contributing factors.
I have to admit, if this paper had been written by someone other than Mech, I’d probably have not have paid as much attention to it. This is because I find myself wanting to believe the wolf-as-ecological-mediator narrative. I freely admit, I’m biased in this regard. But the fact that a wolf biologist as learned and experienced as Mech produced this definitely caught my eye. (more…)