A report from TRAFFIC and WWF has said the national rail network in India is the preferred method for transporting tigers and their parts. It found that a minimum of 1,755 tigers were seized between 2000 and 2015 - an average of more than two animals per week.

Published ahead of a critical debate on illegal tiger trade at the world's largest wildlife trade meeting underway in South Africa, the report says at least 30 per cent of the big cats seized in 2012-2015 were captive-sourced tigers. "During the 16-year period under review India has recorded the greatest number of seizures of all Tiger Range Countries (TRCs), accounting for 44 per cent (355) of the total - a minimum of 540 Tigers seized, accounting for 30 per cent of the total.

"Location information demonstrates that while the southern region remains a hot spot, there also appears to have been a greater number of seizures reported in the central zone in and around Madhya Pradesh," the report 'Reduced to Skin and Bones Re-examined' sent by WWF said.

With only an estimated 3,900 tigers left in the wild, evidence indicates that an increasing number of seized animals undoubtedly originate from captive breeding operations. The report said that a smaller cluster of seizures has also been observed along the border of Nepal in Uttar Pradesh.

"The research found that the national rail network in India is the preferred method for transporting tigers and their parts and is greatly determined by the fact that many train lines traverse through many protected areas across India, in contrast to the national bus service for example," it said.

It said that despite the highest number of seizures recorded by India, the overall trend line indicates a statistically significant decrease in the number of seizures being reported, particularly since 2010, as described earlier in the report.

WWF said this week representatives from more than 180 countries meet at the 17th Conference of the Parties (CoP17) to the Convention on International Trade in Endangered Species of Wild fauna and flora (CITES).

Conservationists will be urging those countries with tiger farms - including China, Vietnam, Thailand and Laos - to commit to providing a clear time frame for the phasing out and final closure of these facilities.

In a move to combat the poaching of tigers, India is asking other governments at CoP17 to share photographic evidence of seized tiger skins for comparison with camera trap images of wild tigers held in a database.

"India remains vulnerable to tiger trade along the country's borders in the east and north. This knowledge, based on sound analysis of past data and information, should help in optimising the resources at our command", said ShekharNiraj, Head, TRAFFIC India.

WWF said that the report also highlighted an apparent rise in the seizures of live tigers, particularly in Thailand and Vietnam, with 17 animals seized from 2000-2004 and 186 animals in the last four years. It is widely believed the increase in live seizures is directly related to the rise in tiger farms.

Recent seizures have highlighted hot spots for trafficking in Vietnam, which has come under scrutiny at the CITES conference for its lack of progress in tackling the illegal trade in rhino horn, ivory and tigers.

"This analysis provides clear evidence that illegal trade in tigers, their parts and products, persists as an important conservation concern. "Despite repeated government commitments to close down tiger farms in Asia, such facilities are flourishing and playing an increasing role in fuelling illegal trade," said Steven Broad, Executive Director, TRAFFIC.