The finding represents a major step forward in the study of this species, but also suggests that there may be more discoveries to be made in the country.
First spotted in India in 1867, the large-billed reed warbler (Acrocephalus orinus) didn’t appear again until 2006, this time in Thailand.
In fact, so little was known about this tiny, greenish-brown bird that the conservation organization Birdlife International had long dubbed it “the world’s least-known bird species.”
And it stayed that way until recently, when the bird’s first-known breeding site was finally found in the remote, peaceful Wakhan Corridor in northeastern Afghanistan.
Robert Timmins, a researcher for the U.S.-based Wildlife Conservation Society (WCS), discovered the site by chance when he made this first-known audio recording of the species in 2008.
Timmins tells RFE/RL that the discovery and later return visits opened a flood of new information that is completely changing perceptions of the large-billed reed warbler.
He says the bird, previously perceived as a “cryptic” species, is now seen as a long-distance migrant with a postulated range stretching from Central Asia to Southeast Asia.
"Some people in the past had said that maybe it was just a local bird that didn't really move very far. The genetics of the bird in Thailand and of these ones in Afghanistan are so similar that they must be from the same population migrating back and forth. Just knowing that it has this migration adds a huge body of knowledge," Timmins says.
The Wakhan Valley is sandwiched between Tajikistan, Pakistan, and China, and surrounded by some of the highest mountains of the Hindu Kush. This arid habitat supports a wide range of large mammal species, including the Marco Polo sheep (Ovis ammon polii), the Siberian ibex (Capra ibex sibericus), the lynx (Lynx lynx), and the snow leopard (Uncia uncia).
Timmins says the discovery of the breeding site indicates that the Wakhan Corridor and Afghanistan as a whole still holds biological secrets.
"During the survey I also found at least two species that had never been recorded in Afghanistan before -- one was a rosefinch and another was a snow cock. And many more things remain to be discovered in that country as a whole," Timmins says.
The discovery follows months of detective work. A preliminary paper on the finding appears in the latest edition of “BirdingASIA,” the magazine of the Oriental Bird Club.
The story of the discovery begins in June 2008, when Timmins’ survey brought him to the riparian bushlands where the Wakhan and Pamir rivers meet to form the Amu Darya River. Timmins heard and taped a singing reed warbler.
A subsequent visit to a natural history museum in Britain to examine bird skins demonstrated that the observed birds were not from the species previously assumed.
In June 2009, WCS researchers returned to the site, deploying mist-nets and broadcasting the recording of the song. Almost 20 warblers were caught for examination and feathers were collected for DNA.
Later lab work comparing museum specimens with measurements, field images, and DNA showed that Timmins had found the first-known breeding population of large-billed reed warblers.
The researchers also found that the bird’s breeding ground, a partially cultivated river area, is an "oasis” for more than 50 species of resident and migratory birds. It is also a riverside corridor for a wide variety of mammals such as the Cape Hare (Lepus capensis), the Stone Marten (Martes foina), and the Grey Wolf (Canis lupus).
The discovery is good news from troubled Afghanistan, a country which, Timmins says, must be safeguarded against habitat loss.
"These thickets or formations of bushes along the rivers form a sort of a real magnet of vegetation for species that congregate in the area for shelter. Local human populations also use these thickets. There's a dynamic equilibrium there," Timmins says.
Investigations conducted late last year on Tajikistan’s side of the upper course of the Amu Darya River showed that riparian bushland was largely nonexistent or very impoverished on the riverbanks.
Scientists say conservation measures on the Afghan side of the river will have to consider the development of alternative fuel resources for local inhabitants to replace wood cut from the riverside scrub.
They also say existing cultivated lands also need to be improved to provide an alternative to clearing riparian bushland for growing crops and grazing livestock.
WCS is currently the only organization conducting ongoing scientific conservation studies in Afghanistan.
In partnership with the Afghan government, WCS has contributed to the creation of the country's first national park at Band-e-Amir in 2009, and to the set-up of the first-ever Afghan list of species protected from hunting, harvesting, and trading.