Your News story 'Acclaimed photo was faked' (Nature 451, 1034–1035; 2008) indirectly calls into question the impact of China's Qinghai–Tibet railway on the migration of Tibetan antelopes. As zoologists officially responsible for evaluating the impact of the railway on plateau wildlife, we have been monitoring the situation annually from the time construction began in 2003, through its completion in 2006 and on to the present.

During the railway's main construction period, the antelopes were very much disturbed. But they soon adjusted their migration routes, westward in spring and eastward in August, to avoid most human activity. The railway has many underpasses, including 143 that are more than 100 metres wide; these wide underpasses have a total width of 46 kilometres. Adding in the many smaller ones, underpasses encompass 259 kilometres of the antelopes' main range.

Contrary to any impression that might have been conveyed by the faking of the acclaimed photograph, the animals have readily adapted to these underpasses, at present concentrating on only a few of them. In 2006 we counted 2,952 antelopes migrating east, of which 98.17% crossed by using the wildlife underpasses.

Building bridges? Migrating antelopes are not put off by the new railway. Credit: Q. YANG, L. XIA

A highway built in the 1950s runs parallel to the railway, at about 500–1,500 metres away in our research area. (Outside our research area, the distance between road and railway ranges from 200 metres to 35 kilometres.)

The antelopes usually wait for a lull in the heavy flow of daytime traffic before hurrying across the road. Some animals even forage along the highway, seemingly ignoring the cars and trucks.

It seems, then, that the Tibetan antelopes have largely adapted to the presence of the Qinghai–Tibet railway. As the area develops further, care must be taken to ensure that these animals can continue their ancient pattern of migration.