IS REWILDING AMERICA A GOOD IDEA?
by Whit Gibbons
March 19, 2006
and mastodons. Giant ground sloths and Pleistocene giant beavers. Saber-toothed
tigers and America grasslands cheetahs. All are extinct. Seeing reconstructions
of such creatures and their habitats recently in the Smithsonian Natural
History Museum in Washington, D.C., and the State Museum in Columbia,
S.C., made me muse. What would it have been like to live when such magnificent
megafauna roamed the landscape? Would the thrill and excitement of experiencing
them in the wild have outweighed concerns for personal safety? We could
the well-documented disappearance of most of Americas megafauna,
a commentary titled Re-wilding North America in the scientific
journal Nature introduced me to a new word and a controversial concept.
Josh Donlan and Harry Greene of Cornell University with several colleagues
have proposed a rewilding effort that would bring free-ranging lions,
elephants, and camels to the southwestern United States. The verb rewild,
which is not yet in the dictionary, means to replenish a region with present-day
extant species that are closely related to wild species that formerly
inhabited the area but became extinct. The proposal to rewild North America
brings to light an intriguing conservation approach.
plan advocates establishing populations of large wild animals, mostly
African and Asian mammals, in western North America as a conservation
strategy to restore extinct species by replacing them with closely related
modern species. The extinct forms disappeared approximately 11,000 to
13,000 years ago near the end of the Pleistocene geologic epoch. Pleistocene
rewilding would be accomplished through careful manipulation and
management of the ecosystems into which the species are introduced. The
authors hope to shift the conservation biology mindset from one of constantly
dealing with extinction to one of actively restoring natural processes.
They propose a positive, proactive approach rather than simply reacting
to the downward spiral of species declines and extinctions.
justify the rewilding proposal on the basis of four observations that
are difficult to dispute. First, no pristine environments remain because
of the worlds most destructive invasive species, humans. Second,
environmentalists are too often viewed as doomsday prophets rather than
environmental saviors, especially when they emphasize the reality of the
previous sentence. The authors seek to remedy this widely held attitude.
Third, some areas, notably the Great Plains, with declining human populations
may serve as a region for innovative conservation approaches. Finally,
humans are ethically responsible and should attempt to rectify human-caused
declines and extinctions of large vertebrates.
plan has several phases. The least controversial to most people is the
proposed translocation of Bolson tortoises, one of the few extant species
under consideration in the rewilding effort. The desert-dwelling tortoises,
which can weigh more than a hundred pounds, once ranged into the U.S.
Southwest but are now restricted to a small region in Mexico. One proposal
is to move tortoises to Texas and New Mexico, thereby reintroducing them
to where they once lived.
among mammals to be introduced to the Southwest are Przewalskis
horses, a rare species native to Mongolia. The intent is to replace the
ecovoid left by the extinction of North American horses. Conservationists
who consider free-ranging mustangs and donkeys to be destructive invasive
species will probably have issues with this part of the plan. But the
most exciting phase is to introduce free-roaming African cheetahs, Asian
and African elephants, and African lions. The first stage will be to work
with animals that are already in captivity on private lands in the Southwest.
addresses obvious concerns that might be voiced including introduction
of alien diseases, unanticipated interactions with native animals and
plants, and negative contacts with people. Imagine the story behind the
first road-killed elephant, or the poodle that tries to outrun a cheetah.
But the article also makes the indisputable point that most humans are
intrigued by large animals, and later phases of the plan would include
the development of ecological history parks in the Great Plains,
as well as a positive step toward preventing extinction of critically
endangered African and Asian species. A move to rewild America will have
its supporters and detractors. Some will think it captivating and doable;
others will think it a wild idea too reminiscent of Jurassic Park.
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