Once upon a time, a walk through a shady floodplain forest in northern Iran or southern Kazakhstan might have landed you some face-time with a tiger.
That thrilling if terrifying possibility no longer exists, but a new scientific assessment suggests that Panthera tigris could once again occupy at least a little portion of this most northwesterly reach of its historic distribution.
Specifically, we're talking here about the vanished Caspian tiger, which – along with the Amur and Bengal subspecies – was among the heftiest of its kind: a big male could tip the scales well beyond 500 pounds.
The Caspian tiger once roamed many thousands of square miles between eastern Turkey and northwestern China, where it haunted reed jungles and gallery forests called tugai composed of water-loving trees and shrubs. In these mucky wildernesses – surrounded in many places by arid steppes and mountains – the big, bearded tiger stalked Bactrian deer, roe deer and wild boar.
By the nineteenth century, however, the Caspian tiger was rapidly losing ground to humankind: its marshes and riverine woods turning to cropland, its hoofed quarry being shot out, and the cat itself relentlessly in the crosshairs – particularly once the Russian government declared open war on it. The tigers were gone from most of their range by the mid-1900s. The last documented individual was killed in southeastern Turkey in 1970, though some believe the cats held on awhile longer in northern Iran.
Lately, though, conservationists have added a spark of hope to this sad and familiar story. Recent DNA analysis suggests that the Caspian tiger is, from a genetic standpoint, essentially the same beast as the Amur tiger, which – though itself perilously close to extinction due to habitat loss and human persecution – still survives in the forests of the Russian Far East.
A 2009 study suggested that a common ancestor of the Caspian and Amur tigers (probably the Indochinese tiger) expanded into Central Asia from China along the so-called Gansu Corridor between the Tibetan Plateau and the Gobi Desert. From there, tigers spread northeast into Siberia. For thousands of years, the authors speculate, one (very big) tiger ruled from the lush forests of the Caspian Sea's south shore to the remote coast of the Sea of Japan – before, some two centuries ago, humanity cleaved this territory in two, separating the Caspian tiger from the Amur.
Because the Amur tiger shows such genetic kinship to the Caspian, researchers propose that restoring the lost cats is possible.
"The idea of tiger reintroduction in Central Asia using the Amur tiger from the Russian Far East as an 'analog' species has been discussed for nearly ten years," Mikhail Palysyn of the State University of New York's College of Environmental Science and Forestry (ESF) said in a press release.
Among the main roadblocks, though, has been identifying suitable habitat, given how few large tracts of wetlands and tugai remain in the Caspian tiger's former range.
Now, a recent study carried out by ESF scientists with WWF-Russia has pinpointed a promising swath of territory in southeastern Kazakhstan: the riverine forests and reed beds of the Ili River delta and the southern shores of Balkhash Lake into which the Ili flows.
The researchers estimated 2,700 square miles or so of this landscape could support nearly a hundred tigers within 50 years. "Re-establishment of tigers in Central Asia may yet be tenable," they claim.
But the return of the big cats depends on a number of significant conditions, among them both Chinese and Kazakh officials allocating enough water in the basin to restore suitable tiger prey and help ecosystems thrive. There's also the possibility that transplants from the Russian Far East may not adapt well to the drier conditions of their new home.
What's more, there are the concerns of local communities in the Ili-Balkhash region to consider. Though releasing a half-ton cat anywhere is liable to make locals leery, the researchers note that there is in fact a fair amount of support for tiger restoration in Kazakhstan, largely because it could boost ecotourism.
The possibility of bringing the tiger back to a portion of its former range marks a welcome breath of optimism in what, overall, is a grim global picture for this regal carnivore.
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Top header image: George Paterson, Flickr
Animal Behaviour
Endangered
Endangered
