Conservation group WWF Monday urged timber firms to drop plans to clear Indonesian forest areas where infra-red cameras have captured footage of rare Sumatran tigers and their cubs.
The video recorded in March and April shows two mothers with four cubs and another six of the critically endangered big cats in the Bukit Tigapuluh wildlife reserve in eastern Sumatra.
"That was the highest number of tigers and tiger images obtained... we've ever experienced," WWF tiger researcher Karmila Parakkasi said in a statement.
The 12 tigers are concentrated in locations with good forest cover, which includes natural forest inside a land concession belonging to Barito Pacific Timber, wood supplier to regional giant Asia Pulp and Paper (APP).
"This video confirms the extreme importance of these forests in the Bukit Tigapuluh ecosystem and its wildlife corridor," the WWF's forest and species programme director Anwar Purwoto said.
"WWF calls for all concessions operating in this area to abandon plans to clear this forest and protect areas with high conservation value," he added.
"We also urge the local, provincial and central government to take into consideration the importance of this corridor and manage it as part of Indonesia's commitments to protecting biodiversity," he said.
The group's spokeswoman Desmarita Murni said that the Bukit Tigapuluh area was designated by the Indonesian government during last year's Tiger Summit in Rusia as one of six priority tiger conservation areas.
"This is one of Indonesian government commitments in its national tiger recovery plan they pledged during the summit of world leaders in Russia," she told AFP.
"They have to ensure that its commitment is well implemented."
There are fewer than 400 Sumatran tigers left in the wild, among a global tiger population of just 3,200 -- down from 100,000 a century ago.
Environmental activists say the animals are increasingly coming into contact with people as a result of their natural habitat being lost due to deforestation for timber and palm oil plantations.
President Susilo Bambang Yudhoyono has been under pressure from environmentalists to implement a promised two-year moratorium on the clearing of natural forest and peatland, which was due to begin January 1.
Norway agreed in May last year to contribute up to $1 billion to help preserve Indonesia's forests, in part through the moratorium.
WWF warned last year, during the Year of the Tiger, that the species is on course for outright extinction by 2022 -- the next Year of the Tiger under the Chinese calendar.
Thirteen countries host fragile tiger populations -- Bangladesh, Bhutan, Cambodia, China, India, Indonesia, Laos, Malaysia, Myanmar, Nepal, Russia, Thailand and Vietnam.
Russia is the only country to have seen its tiger population rise in recent years. It had just 80 to 100 in the 1960s but now has around 500 -- raising hopes that the majestic creature can be saved if decisive action is taken.
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