Fence fix mends Mongolian mammal migrations

Adrian Burton

They were a few small steps for an Asiatic wild ass (Equus hemionus hemionus ), but the first the subspecies had taken into Mongolia's Eastern Steppe for 65 years. Thousands of Mongolian gazelles (Procapra gutturosa ) and goitered gazelles (Gazella subgutturosa ) would do the same. Pictures just released of events in March 2020 reveal that lands from which these animals had been excluded for decades were once again being accessed, and all because the Trans‐Mongolian Railroad created some gaps in its track fencing.

The phenomenon is a consequence of the Trans‐Mongolian Railroad “Wildlife Friendly” Fence Corridor Project, run by the Wildlife Conservation Society (WCS) in conjunction with the Ulaanbaatar Railroad Authority, the Mongolian Academy of Sciences, and the Mongolian Government. The project aims to remove parts of the fencing running along both sides of the Trans‐Mongolian railway, thereby allowing wildlife to cross.

When work on the railway began in 1941, no one was thinking about migrating mammals. By 1961 the 1115‐km line was finished, crossing Mongolia's vast steppelands and connecting the Russian and Chinese railroad systems via Ulaanbaatar. But fencing installed to prevent trains from being delayed by collisions with animals disconnected the land on either side of the tracks. Today, 46 trains use the line daily, accounting for over 60% of the value of all freight entering Mongolia; it's easy to see how minimizing delays seemed paramount.

“But things are changing”, explains Kirk Olson, WCS Mongolia Conservation Director (Ulaanbaatar, Mongolia). “Mongolia is reassessing the value of its wildlife, and is looking for ways to balance its protection with the need to develop infrastructure. Taking down just two sections – totaling 1.3 km – of this fence has already allowed thousands of large mammals [access to] new grazing. Before, the fence entangled or starved thousands of gazelles every year. With these fence gaps, a small number of collisions [with trains] may occur, but the continuity of migratory species is much better safeguarded. It's not a bad trade‐off.”

More gaps are planned. “If they are truly necessary, new roads and railroads must take the needs of migrating animals into account from the beginning”, says Takehiko Ito (Tottori University; Tottori, Japan). “This news shows us that we can coexist with wildlife.”

The first to cross…

WCS