Final footprints for Siberia's big cats?

Siberian tigers have been spotted again in China's northernmost province, where they were thought to be extinct in the wild.

Vladivostok, Russia -- Heavy winter snowfall in Russia's Far East has hit rare predators such as the leopard and tiger hard, the World Wildlife Fund for Nature (WWF) says.

Sika and Roe deer, as well as wild boars could also die en masse from starvation in the coming months in Primorskii, near Vladivostok in Russia's east, according to the WWF.

These are the main source of prey for both the Far Eastern leopard and the Amur or Siberian tiger, meaning the survival of the big cats is under threat.

The cold weather is just another factor for conservationists to consider, after poaching and habitat destruction have seen numbers of both species diminish.

The Siberian forest has been shrinking because of logging and urban expansion and is now so sparse that the animals are isolated in habitat "islands", the WWF says.

This has reduced their hunting grounds and increased dangerous encounters with people and livestock.

Knock-on effect

The Primorskii area, near the border with both China and North Korea, is home to most of the estimated 450 remaining Amur tigers.

Already this year Sika deer, in the region's breeding farms have been dying from starvation at a rate of up to eight animals per day.

Without additional forage, as many as 80 to 90 percent of the wild deer and grazing animals, collectively known as ungulates, living in south-western Primorskii may die, says the WWF.

This will have a detrimental knock-on effect on the tiger and leopard populations.

Conservation bodies have stressed the need to boost the numbers of deer and other grazing animals in order to preserve the Amur tiger and Far Eastern leopard, although a new program is yet to materialize.

Clearing roads, cutting low hanging tree branches for grazing, and bringing in additional forage are seen as some measures that will encourage greater deer numbers.

Poaching and funding

Conservation over the last few years has helped the number of Amur tigers reach an almost sustainable level, although leopard numbers are much worse off.

Poorly equipped anti-poaching patrols have been organized in the region with protected habitats demarcated -- producing successful results and an increase in tiger numbers.

However, the biggest blow came with the abolition of two main federal Russian environmental agencies in 2000.

This has led to uncertainty surrounding the funding and coordination of conservation efforts surrounding these endangered predators.

World's largest tiger

As the largest tiger in the world, standing taller than its Bengal relative, the Amur wild cat lives in the Sikhote-Alin mountains, in the far east corner of Russia.

It is a vast area sparsely populated by humans, yet extensive hunting reduced the tiger's numbers to below 100 in the 1930s.

Only later in the 1940's did it receive state protection, which resulted in a gradual recovery, of numbers.

The collapse of the Soviet Union meant that the tigers were again once more were under the threat of the poacher's gun.

Since then, several wildlife organizations have worked closely with Russian environmental ministries and scientific institutes and have managed yet again to haul the Amur tiger back from the brink.

However, the weather may have the last word on conservation efforts.