ECOLOGICAL CLEANSING - The New Wild: Why Invasive Species will be Natures Salvation - page 63

Panther habitat or not, the revegetated hole was not the pristine wetland that the parks people wanted.
A pragmatic approach would have been to leave the place as it was. But after two decades of failed
efforts to root out the “weeds,” park authorities decided on a final solution. They would rip out all the
vegetation, strip the soil back to bare rock, and start again from scratch. “I was incredulous,” says Ewel.
Giant scraping machines removed some seven million metric tons of soil, dumping it in mounds that
remain to this day. 35 It worked, after a fashion. Eradicating every last trace of the invasive vegetation
did allow some native wetland plants to colonize the area. But there is an unanswered question about
what to do with the twenty-five thousand dump-truck loads of soil piled up.
And what about the panthers? Concerned about the possibility that the ecological restoration might
result in their extinction, park authorities augmented their stock with some females from Texas. The
newcomers are a different subspecies but a good enough match for breeding. There are now 160 pan-
thers in Florida, a mix of the Florida and Texas subspecies and a growing number of hybrids. Some
taxonomists talk of deleting the distinction between the subspecies altogether. Ewel is not impressed.
“Florida's state mammal is now a novel hybrid,” he told me. A subspecies of an iconic cat has been sac-
rificed in order to fill the Hole-in-the-Donut.
Was it worth it? Only if you think there is no value in unique ecosystems such as the rich panther
habitat created where the farms had been. Only if you think that spending tens of millions of dollars on
trying to put back your notion of the pristine is conservation money well spent. Only if you forget about
the disappeared subspecies. Only, perhaps, if you have no sense of proportion.
That valuable commodity often seems to go missing where alien species are concerned. Ecologists
and their backers are overcome by a cleansing zeal. The most cockeyed story of alien extermination I
have come across is the martyrdom of the ruddy duck. Bird-watchers don't often condone the shooting
of birds. And they are often rather indulgent about foreign flocks, perhaps for the sheer joy of seeing
something new through their binoculars. But the ruddy duck, though it has been resident in Britain for
the past half century, is different. Oxyura jamaicensis is a North American bird, one of a group known
as stiff-tailed ducks. It is larger than the average duck. And its story is very embarrassing for conserva-
tionists.
The first ruddy ducks arrived in Europe at the invitation of one of the twentieth century's most fam-
ous ornithologists and conservationists. Sir Peter Scott was a friend of royals, founder of the World
Wildlife Fund, star of TV wildlife shows, and knight of the realm—the Sir David Attenborough of his
day. His pride and joy was the Slimbridge reserve for waterbirds, which he established on soggy sugar-
beet fields beside the River Severn in the English West Country. In 1948, soon after the reserve opened,
he shipped in three pairs of ruddy ducks from a collector in Salt Lake City. Scott normally clipped the
wings of foreign birds at Slimbridge, to prevent their escape. But these ducks proved hard to catch and
several dozen of the chestnut-breasted new arrivals evaded the clippers and flew off. By 1960, they were
nesting and breeding widely in reed beds in the surrounding countryside. They did no obvious harm and
fanned out across Britain.
But alarm bells rang when they crossed the English Channel and began heading south, looking for
new nesting sites. Suddenly it looked like an American invasion. Worse, having reached Spain in the
early 1980s, a few of them interbred with the local and endangered white-headed duck ( Oxyura leuco-
cephala ). This species was down to its last ten thousand individuals, a quarter of them in Spain. In 1991,
the interbreeding produced the first fertile hybrid. More followed. 36
Spanish ornithologists were proud of having brought the white-headed duck back from near extinc-
tion in the 1970s. Now they feared losing its genetic purity. They began shooting both the hybrids and
the migrant ruddy ducks, and they launched a public campaign to get the rest of Europe to cull the ruddy