Environment and Society. Paul Robbins

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      Second, the winter ice-bridge that has historically existed between the island and the mainland has all but disappeared. This vital connection allowed wolves in search of prey to cross the ice, and support and diversify the local wolf population. As winters have warmed, a result of human-caused climate change, and the ice cover of Lake Superior has become less reliable, this crucial connection has now failed, further endangering the wolves of Isle Royale.

      Just as inevitably, the Canadian shores across from Isle Royale have undergone significant development investment in recent decades. With more human activity in the vicinity of historic winter migration, the movement opportunities for the wolves are even worse.

      Finally, the small size of the population has encouraged genetic bottlenecks, a condition where genetic diversity plummets, further reducing the changes of the population’s survival. Sings of inbreeding, stillbirths, and blindness have set in.

This apparently grim news reflects what ecologists increasingly refer to as ecological novelty, a condition where whatever ecological systems occurred in the past have been swept away by new conditions, as where the climate changes, new species interact with earlier ones, and invasion and diseases introduce new and complex dynamics, owing to migration or introductions. “Novelty” is technically “the degree of dissimilarity of a system, measured in one or more dimensions relative to a reference baseline” in “the present or a time window in the past” (Radeloff et al. 2015, p. 2051). Put simply, it is a condition of change, relative to whatever we have seen before, often reflecting a kind of “one way ticket” to a situation from which there may be little hope of natural return. Whether it is domesticated cats running amok and eating wild birds, or the ice melt that imperils the polar bear, this is the condition of many treasured places and wildlife around the world.

      Ecological Novelty An ecological condition where human-caused alterations of biotic or abiotic conditions lead to changes at different ecological levels, from organisms and populations to communities, ecosystems, and landscapes

      Ecological processes never go away, of course. Ecology’s rules, laws, and flows continue, only under radically altered conditions, and with whole new sets of players. This means that despair would be insanely premature at Isle Royale. Instead, all of the human-caused forces and changes on Isle Royale invite us to think about what people might do to restore, reimagine, and foster wildlife. Wolf reintroductions could be launched from other land-based populations to the island. More radically, genetic rescue might sample and bank the genes of the existing wolf pack and work to diversify the gene base. Moose populations, which have grown to a potentially disastrously high level, with implications for the land base, might be culled. In short, people could put their hands on the land and guide it to a place where wolves and moose continue to thrive.

      Doing so, however, would more of an effort at rewilding than letting nature “take its course.” Rewilding refers to efforts by people to return landscapes and lost ecosystems by tinkering heavily with them or crafting them from whole cloth, in order to reclaim – or create – landscapes as they might have been before human influence (Kolbert 2012).

Rewilding A practice of conservation where ecological functions and evolutionary processes, which are thought to have existed in past ecosystems or before human influence, are deliberately restored or created; rewilding often requires the reintroduction or restoration of large predators to ecosystems

There is plenty of precedent for such activities. In the sand hills of Nebraska, for example, along the Platte River, hundreds of thousands of migrating Sandhill Cranes (Grus Canadensis) congregate every spring, on the migration south to the Gulf Coast, using the sandbars of the river as nightly perches and protection from predators (Figure 1.1). This stretch of the river is a critical habitat for a booming population of the elegant, strong, and giant birds, and a destination for visitors from around the world every year.

      Figure 1.1 Sandhill cranes of the Platte River. A half million of these birds congregate annually. Source: Diana Robinson Photography/Moment/Getty Images.

      But this is by no means a “natural” condition. Owing to the century-old human damming of the river, the Platte lost its powerful ability to flood, and so its sandbars gave way to shrubby vegetation, overgrowth and habitat loss for cranes and other species. Only by scouring the river bed every year, with gigantic machinery, do people manage to maintain this habitat and allow the critical sandbars of the river to return. The returning birds also glean from nearby famers fields as they rest on their long journey; people are providing a crucial subsidy to their non-human visitors. The Sandhill Crane was on the brink of extinction in the middle of the twentieth century. It has come roaring back in recent years, owing to human’s ability to understand their influence on the environment, and their willingness to consider their responsibility to the land.

More radically, in Flevoland, a province in the Netherlands, wild species are thriving as never before. As in the late Pleistocene (10 000 years ago), Red Deer roam the landscape, feral horses travel in herds, and an ecosystem of foxes and wild birds has arisen, including egrets and wild geese. Aurochs – the massive wild cattle of Europe – have been extinct for centuries, but their human-bred cousins, Heck Cattle, graze the landscape, their long horns and hairy forms rumbling across the marshland (Figure 1.2). This 15 000-acre wilderness, called Oostvaardersplassen, is wholly artificial, and filled with wild life. Remarkably, all this wildlife is thriving in one of the places on Earth most densely populated by people. For safari visitors, who pay US$45 for a visit to the park, there is no question that the place creates a great sense of wonder, as visits to wild places do for most all of us in a world that is increasingly encroached by human activity, pollution, and influence.

      Figure 1.2 Heck Cattle, introduced to replace the extinct Aurochs. Source: Simon Vasut/Shutterstock.

      These views from Canada, Nebraska, and the Netherlands makes our global situation easier to understand, though perhaps no simpler to solve. The contradictory proposition – dramatically transforming the environment in ways that may preserve the environment – is a metaphor for the condition of our longstanding relationship to the non-human world. Nor is this problem rare. Yellowstone National Park in the United States, though heralded as a wilderness, was created through the violent extirpation of the dozens of native tribes who lived in the region, transformed its landscapes, and relied on the resources of what would become a park devoid of people. Coffee plantations throughout Asia and Latin America, though regarded purely as economic and artificial landscapes, often teem with wild birds, mammals, and insects, all beyond the intent and control of farmers, conservationists, or anyone else for that matter. Everywhere we seek some place beyond people, the marks of human creation and destruction confront us, and wherever the works of humans are in evidence, there are non-human systems and creatures, all operating in their own way.

      Decisions made in places like Isle Royale, therefore, cannot be made solely on the basis that the region is a “natural” one, nor a “social” one. The area is simultaneously neither and both, with animals, plants, and waterways springing from human interventions, creating altogether new habitats and environments. Wildlife parks and coffee plantations are both landscapes of the Anthropocene, therefore, one term for our current СКАЧАТЬ