FOR 200 years, this "ninja" of the forest has eluded explorers.
The Sunda slow loris, a nocturnal primate with panda-like dark circles around its large eyes, is so painfully shy it could barely be found in our forests.
Famed British naturalists in the colonial days tried and failed.
And it is still giving local scientists the slip.
The first-ever local study of the native cat-sized animal has reinforced how notoriously elusive it is, throwing up the need for many more longer-term surveys in order to study it properly.
In 108 night-time hours spent surveying seven forested sites in 2007 and 2008, just one Sunda slow loris, which is very sensitive to light and sound, was seen.
It was spotted in the Nee Soon swamp forest, a permanently flooded freshwater swamp located near Upper Seletar reservoir.
Fewer than 250 of the poorly studied, critically endangered creatures remain here on the mainland and on Pulau Tekong. Its exact population is unknown.
It is a similarly vague picture elsewhere in the region, where it is so rarely encountered that data is limited.
Lead researcher Fam Shun Deng, president of the South-east Asian Biodiversity Society, noted that even expert British naturalists in the 19th century, who collected thousands of animal specimens from the region, did not have better luck.
"For all their prolific collecting, there is not a single wild collected loris specimen in any museum in the world that is from Singapore," he said.
The Sunda slow loris is usually solitary, and spends almost all its time in treetops.
Unlike humans, it has excellent night vision. It feeds on tree gum and insects.
In Indonesia, it is known as malu malu or "shy one" because it freezes and covers its face when spotted.
The one-year study done in collaboration with the National Parks Board did however turn up encouraging data showing that loris sightings have increased sharply in recent decades.
From just a handful of sightings reported in the four decades prior to 2000, 32 have been reported in the decade and a half since.
However, Mr Fam cautioned that the increase in sightings may be simply because more field work is being done in Singapore's forests.
To further complicate the picture, the study found that the numbers are possibly inflated by an illegally smuggled exotic species, the Pygmy slow loris.
The loris' popularity in the illegal pet trade means owners could be releasing them once they tire of them, it concluded.
There have been at least six cases since 1999 of lorises being confiscated by the authorities, the most recent of which was last June.
A Pygmy slow loris was also spotted in the survey.
Findings from the study were published last month in the international journal Endangered Species Research.
The paper calls for more action to halt the illegal trade.
It also urges forest gaps to be bridged by planting trees or building rope bridges, to expand the lorises' habitat.
In addition, it recommends more "sustained, focused and regular surveys" to establish the precise Sunda slow loris population.
Wildlife consultant Subaraj Rajathurai said: "Without having the facts, it is very difficult to create policies to protect these animals in the long term."
This article was first published on August 20, 2014.
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