Social media outlets including Facebook and Instagram are increasingly being used in Asia as platforms for the illegal trade in a range of threatened species such as orangutan and sun bears, a wildlife monitor has said.

UK-based wildlife monitor Traffic said in a report, released to coincide with World Wildlife Day on Thursday, that the trend poses a new major threat to wildlife in a region where products derived from exotic or endangered animals are widely sought for traditional medicines or prized as pets.

"Traders are clearly moving to non-conventional methods of sale such as utilising online portals and social media in order to evade detection, reach a broader audience, and increase transaction efficiency and convenience," Traffic's report said.

Growing numbers of traders are using closed groups on Facebook and password-protected online forums to reach Asian customers, it said.

The wildlife monitor said that in one month in China last year, thousands of ivory products, 77 whole rhino horns, and large numbers of endangered birds were found advertised for sale on sites such as QQ and WeChat, which are popular in China.

Traffic's report focused heavily on Malaysia. Over a period of five months last year, on a daily basis it monitored 14 Facebook wildlife-trading groups catering to customers in Malaysia, counting tens of thousands of active members.

During the observation period, scores of traders put up more than 200 individual posts offering to sell live wild animals, ranging from rare birds to orangutans and sun bears, it said.

Kanitha Krishnasamy, a senior programme manager for Traffic in Southeast Asia who co-authored the report, told Al Jazeera that since the assessment period ended in April, many more Facebook groups have been created.

Often, ads with photos were uploaded to sites such as Facebook or Instagram, while bargaining for the animals took place over other platforms like WhatsApp in Malaysia and Blackberry Messenger in Indonesia.

READ MORE: Myanmar's wildlife trafficking hotspot

"Trading appears to be very relaxed and traders will happily provide their contact details and will sometimes offer to deliver the animal to the buyer's home address," said the report.

Facebook groups can quickly change their names or shut down and pop up in another guise, highlighting the challenges facing law enforcement.

Traffic said it was working with enforcement agencies in many countries on the issue and also was in contact with Facebook.

It called for "closer collaboration between law enforcement agencies and Facebook".

But Traffic's report quoted a Facebook spokesperson saying the social media giant does not allow trade in endangered animals through its platforms and was "committed to working with Traffic to help tackle" the problem.

A spokesman for Malaysia's Department of Wildlife and National Parks said it was aware of the issue and had taken measures that had resulted in arrests.

READ MORE: 101 East tracks down wildlife smuggler

Krishnasamy said that since 2013, Malaysian authorities have arrested at least 54 wildlife traders, made more than 43 seizures, and rescued more than 60 different species.

She also said that the "global scale" of the illegal trade has made it much more difficult for law enforcement agencies to crack down.

With additional reporting by Ryan Rifai