Numbers of endangered bulbuls show slight rebound on Pulau Ubin

NEO CHAI CHIN Today Online 23 Feb 17;

SINGAPORE — While their counterparts in the region have been hunted relentlessly for the caged-bird trade, at least 202 Straw-headed bulbuls have found a safe home in Singapore and have grown in numbers on Pulau Ubin.

The population of the endangered songbird species on the island grew at nearly 4 per cent per year over the past 15 years to at least 110, while numbers on the mainland have held steady.

These findings by six Singaporean birdwatchers were published recently in the journal Bird Conservation International.

The bird’s conservation status was raised last December from “vulnerable” to “endangered” on the International Union for Conservation of Nature (IUCN) Red List, which classifies species at high risk of global extinction.

With the global population of the bird estimated at 600 to 1,700 individuals, the group in Singapore may easily comprise up to one-third of the world’s remaining wild Straw-headed bulbuls.

The authors added that the estimate of 202 is likely to be conservative, given that surveys of Singapore’s western catchment area were not comprehensive due to limited access.

Mr Yong Ding Li, a PhD student at Australian National University, who led the study, said: “Across much of South-east Asia, the Straw-headed bulbul has been relentlessly trapped from the wild to be later sold in the bird markets of Java, Kalimantan, Sumatra and Peninsular Malaysia.

“The bird has gone extinct in Thailand and parts of Indonesia where it used to be found, including the whole island of Java. It has also declined across Malaysia.”

In contrast, new sites for the bulbul have been discovered here recently.

Co-author Ho Hua Chew, who is also vice-chair of the conservation committee at Nature Society (Singapore) (NSS), said: “The bulbul is found in pockets of woodland such as Pulau Ubin, Bukit Brown and Khatib Bongsu. More should be done to protect such places, which are currently outside the existing reserves.

“Other biodiversity could also benefit from the conservation actions targeting the bulbul.”

The study’s other authors are brothers Lim Kim Seng and Lim Kim Chuah, Ms Trixie Tan and Mr Teo Siyang.

The study made use of more than 15 years’ data of the NSS’ Annual Bird Census and the authors paid tribute to such regular surveys and the support of volunteers.

Mr Lim Kim Seng, the society’s coordinator of the annual census, said that citizen science efforts to monitor wild bird populations in Singapore have been led by the NSS’ Bird Group since 1986.

“On a predetermined morning, scores of enthusiastic members will sacrifice sleep to be out in the wild at their assigned sites, counting the birds for the census,” he said.

“Over the past two decades, these censuses have allowed us to track population trends of threatened species such as the globally endangered Straw-headed bulbul.”

While encroachment and trapping pressures are lower in Singapore than elsewhere in South-east Asia, the authors said that some pressures exist in the form of habitat loss — the bird has been found in areas of unprotected secondary woodland that were later cleared.

Potentially invasive bird species such as the White-crested laughingthrush may also compete with the bulbul for food, and the population in Singapore may be vulnerable to inbreeding and diseases, they said.

The authors called for a species recovery plan coordinated by stakeholders across Indonesia, Brunei, Malaysia and Singapore. In Singapore, the authorities could work with non-governmental organisations and zoos to designate the Straw-headed bulbul a flagship species for conservation since it is “easy to identify by amateur naturalists”.

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