The reason why large carnivores such as tigers eat cattle or other livestock, in places where predators and people share space and resources, is thought to be due to wild prey scarcity. However, a study published a few days ago in Open Science shows that this is not necessarily true. Simulated scenarios of livestock predation based on ground data predict that snow leopards in Asia will still prey extensively on livestock even when wild prey is available in high numbers.
The snow leopard feeds on hoofed animals (ungulates) including the Siberian ibex, blue sheep, urial and argali in the Himalayas. But ungulates also include livestock such as cattle, yak and horses, and these are killed in hundreds, annually.
To find out whether snow leopards turn to livestock because wild prey populations are not sufficient, scientists from the Snow Leopard Trust (SLT), Nature Conservation Foundation (NCF), National Centre for Biological Sciences (NCBS), Bengaluru, University of Aberdeen and St. Andrews University obtained wild prey and livestock numbers from multiple sites in India and Mongolia. They used camera traps and genetic analyses of snow leopard faeces to identify individuals and arrive at snow leopard numbers at each site. The team also ascertained the preferred prey of snow leopards by examining prey fur (from the faeces). Using these data, the team finally modelled different ecological scenarios: whether livestock predation would increase or decrease with changing livestock and wild prey numbers.
Prefer wild prey
The scientists found that snow leopards did indeed prefer wild prey over livestock. The number of snow leopards increased only with increasing wild prey and not livestock: only wild prey therefore, is crucial for snow leopards. Oddly, modelled results predict that when both wild prey and livestock numbers are high, snow leopards will kill more livestock. This is because while individual snow leopards may kill fewer livestock in this scenario, the cumulative effect of all snow leopards put together is increased livestock predation.
“Livestock have degenerated anti-predatory abilities as a result of artificial selection for other traits and living in a human-mediated environment,” says Charudutt Mishra, Science and Conservation Director of Snow Leopard Trust and scientist at Nature Conservation Foundation. “Their large herds and more predictable distribution also make them vulnerable to predation. Our data show that livestock will get killed, irrespective of the abundance of wild prey; that is an important lesson for livestock management.” These predictions will be tested in future work, he adds.
Livestock predation
“We should anticipate livestock predation regardless of high numbers of wild prey and have sufficient measures to tackle it,” says lead author Kulbhushansingh R. Suryawanshi, Director of the India chapter of the Snow Leopard Trust and NCF scientist.
Better livestock protection and offsetting carnivore-caused economic damage is a must, write the authors. Retaliating to enormous economic losses people kill snow leopards across most of its range in Asia, and this is one of the main threats that the endangered animal faces today.
According to Mr. Suryawanshi, though the study focused only on snow leopards, there are lessons in the study that would be worth considering for other carnivores and livestock predation scenarios, too.
