Indonesian tribesman Muhammad Yusuf believes his conversion from animism to Islam in a government-supported program will eventually make his life easier.

"Thank God, the government now pays attention to us; before our conversion they didn't care," says Yusuf, the Islamic name he has adopted.

Yusuf is a member of the "Orang Rimba" tribe. His small community now gathers around a stilt-mounted wooden hut, while children inside wearing Islamic skullcaps and hijabs enthusiastically recite the Koran.

Not far away, other members of the tribe who remain faithful to the old ways stalk through palm oil trees in a desperate hunt for prey in an area that was once lush Sumatran rainforest.

Stick-thin and wearing only loincloths over their weather-beaten skin, they brandish homemade rifles as they search for their next meal.

Yusuf's group converted to Islam, the predominant faith in Indonesia, and gave up their nomadic ways in January in a bid to improve livelihoods that have been devastated by the expansion of palm oil plantations and coal mines into their forest homelands.

Authorities insist the move is positive but critics say it amounts to a last throw of the dice for indigenous groups driven to desperation by the government's failure to properly defend their rights against rapid commercial expansion.

Indonesia is home to an estimated 70 million tribespeople, more than a quarter of the total 255-million population, from the heavily tattooed Dayaks of Borneo island to the Mentawai who are famed for sharpening their teeth as they believe it makes them more beautiful.

But as a nomadic group, the Orang Rimba -- whose name translates as "jungle people" -- are a rarity.

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Big changes

This photo taken on May 19, 2017 shows children from the"Orang Rimba" tribe -- whose name translates as "jungle people", who have been converted to Islam and given up their nomadic ways, wearing Islamic skullcaps and hijabs as they gather to recite the Koran, in the Batang Hari district of Jambi province. (AFP/Goh Chai Hin)

The 200 who recently converted in the Batang Hari district of Jambi province -- a handful of the approximately 3,500 Orang Rimba -- decided to turn to the Muslim faith after being approached by an Islamic NGO, and the social welfare ministry has helped with the process.

Community leader Yusuf conceded the reason they were converting was because food was increasingly hard to find and they were constantly locked in disputes with companies on whose lands they hunt, rather than due to any deeply-held beliefs.

The tribesman also said that he and his family -- he has 10 children -- wanted to get national identity cards, which would allow them access to public services including education and healthcare. Converting to Islam and settling in one location means they can get the cards.

The decision has meant big changes.

The converts now live in basic wooden huts on stilts and no longer move to a new location every few weeks. They are fully-clothed in items donated by the government and NGOs, having abandoned the simple loincloths and sarongs they wore in the past.

"It's nicer living in a village like this, our lives are better," said Yusuf, whose old Orang Rimba name was Nguyup.

They have not completely abandoned their animistic traditions however -- the tribe believes spirits inhabit the trees and their wavy-bladed daggers -- and view Islam as a religion that overlays their own, ancient beliefs.

Not all of the Orang Rimba are keen to convert however.

Just a couple of hours drive away, a group of about 300 Orang Rimba live under blue, plastic tarpaulins propped up on sticks and subsist by hunting the few animals they can find amid the palm oil trees.

They move on average three times a month in the hunt for new prey, and every time a member of the group passes away, as required under tribal customs.

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Tough existence

This photo taken on May 19, 2017 shows Indonesian "Orang Rimba" tribesmen brandishing homemade rifles and wearing loinclothes, part of a hunting party, setting out through palm oil trees in a desperate hunt for prey in an area that was once lush rainforest in the Batang Hari district of Jambi province.(AFP/Goh Chai Hin)

Their existence is tough, and they appear skinny and malnourished -- but remain steadfastly against conversion.

"According to our tradition, conversion is not allowed," leader of the group Mail, who goes by one name, told AFP.

It is also in part due to superstitious beliefs. "We're afraid if we break our oath, we will be captured by tigers," Mail added.

Conversion of tribespeople to Islam is not uncommon in Indonesia, the world's largest Muslim-majority country, and the government insisted the change would be positive for the Orang Rimba.

Hasbullah Al Banjary, director of indigenous communities at the social affairs ministry, said it was now easier for authorities to provide for the tribespeople as they were not moving around. He said their traditions would not be eroded.

"It’s a creative culture which has local wisdom we need to preserve,” he said.

But indigenous rights defenders insist some tribespeople feel they have no option but to convert.

"I view this as a result of the state failing to protect them," Rukka Sombolinggi, secretary general of leading Indonesia indigenous rights group AMAN, told AFP.

"They turn to clerics or the church in some areas, because they offer protection."

In recent decades, Indonesia has lost huge areas of rainforest -- the habitat for many indigenous groups -- to make way for plantations for palm oil, pulpwood and rubber, as well as coal mines.

Critics say local governments have prioritised making bumper profits by issuing permits for companies to set up operations rather than protecting tribes, who typically have no formal title to areas where they live.

Yusuf said he feels a sense of "tranquility" after converting -- but admitted it had not been a quick fix and his group were yet to receive the coveted identity documents.

"It's now up to the government -- if they care about us they will work on our ID cards," he said.

This photo taken on May 19, 2017 shows a wooden hut where families of the "Orang Rimba" tribe -- whose name translates as "jungle people", now call home in the Batang Hari district of Jambi province.(AFP/Goh Chai Hin)