Straw-headed bulbul endangered in Asia


This video says about itself:

5 March 2011

A pair of Straw-headed Bulbuls engaged in a rhythmic & melodious duet. The repeated song in this clip is short unlike other longer melodious calls usually heard. Perhaps those are for attracting attention, while this one is a song for each other – the birds are obviously quite comfortable on their perch, one bird is busy preening itself, breaking the routine periodically to join the other in the song. This went on for a few minutes; the birds flew off only when I started moving closer, hoping for a better capture.

From BirdLife:

23 Feb 2017

The tiny corner of Asia where an Endangered songbird is thriving

Trapping for the songbird trade has almost proved the ‘last straw’ for the Straw-headed Bulbul, now extinct across much of its range. But a new study has discovered that on a tiny Singaporean island, the bird is bucking global trends.

By Alex Dale

The Straw-headed Bulbul Pycnonotus zeylanicus perhaps isn’t much to look at (at least compared to some other birds of South East Asia), but no-one can deny it has a great set of lungs.

Check out its song in the video above.

But unfortunately, it’s this same rich, powerful melody which is threatening to silence the species forever. As we reported during our 2016 Red List coverage, keeping songbirds as pets is an integral part of South-East Asian culture. In Indonesia in particular, streets are lined with chirping cages, and songbird contests are big business.

But as the streets grow louder, forests are falling silent. The widespread trapping of wild songbirds to meet demand for local bird markets, is driving many species endemic to the area towards extinction – with the prized Straw-headed Bulbul one of the more badly affected.

“Across much of Southeast 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,” says Yong Ding Li from The Australian National University. “The bird has gone extinct from Thailand and most parts of Indonesia where it used to be found, including the whole island of Java. Its populations have also collapsed across Malaysia.”

Hunted to extinction in Thailand and large parts of Indonesia, the Straw-headed Bulbul is in danger of disappearing forever

However, there is one small haven where the Straw-headed Bulbul’s presence isn’t just stable, but actually growing louder: Singapore.

This is according to findings from a recent study led by Ding Li, and published in the journal Bird Conservation International. The study saw authors from The Australian National University and Nature Society (BirdLife in Singapore) gather data from more than 15 years of the Annual Bird Census, a yearly bird survey organised by Nature Society.

The result was an encouraging discovery: wild populations of the Straw-headed Bulbul have steadily risen in Singapore over that time period, and the country is now something of a global stronghold. Indeed, Singapore might now harbour more Straw-headed Bulbuls than anywhere else on the planet.

The increases were not noted on mainland Singapore, however, where populations merely remained stable – although given the Straw-headed Bulbul’s plight elsewhere, even this is a big win. Rather, the increases were documented on the small island of Pulau Ubin, situated north-east of mainland Singapore, and one of the country’s last remaining rural areas. Here, the species’ population increased by nearly 4% a year.

The tiny nation of Singapore may now hold over a third of the world’s Straw-headed Bulbul population

At a conservative estimate (some areas of western Singapore could not be comprehensively surveyed due to limited access), Singapore is today home to at least 200 individuals. Furthermore, new sites have been discovered very recently. With global estimates ranging from 600-1,700 individuals, and trending downwards, Singapore could be harbouring over a third of the world’s remaining Straw-headed Bulbuls.

On mainland Singapore, the bulbul persists in pockets of woodland such as Bukit Brown cemetery and Khatib Bongsu, both of which aren’t part of the current reserve network.

“More should be done to protect such places which are currently outside the existing reserve network,” said co-author Dr Ho Hua Chew from the Nature Society (Singapore), who is also vice-chair of its conservation committee. “Other biodiversity could also benefit from the conservation actions targeting the bulbul.”

he study offers further evidence of the value of citizen science. Without the hard work of volunteers, conservationists on the island would lack the data to determine which habitats are most vital for rare species such as the Straw-headed Bulbul, which has declined so dramatically in recent years that BirdLife uplisted its threat status from Vulnerable to Endangered in the 2016 Red List.

“Citizen science efforts to monitor wild bird populations in Singapore, including the Straw-headed Bulbul, have been led by the Nature Society’s Bird Group since 1986,” says co-author Lim Kim Seng, coordinator of the Annual Bird Census. “On a predetermined morning, scores of enthusiastic members will sacrifice sleep to be out in the wild at their assigned sites, counting birds for the census. Over the last two decades, these censuses have allowed us to track population trends of threatened species such as the globally endangered Straw-headed Bulbul.”

So while Thailand and parts of Indonesia may already have had their last Straw, at least in one small corner of Southeast Asia, the Straw-headed Bulbul can still be heard loud and proud.

The article “Significance of the globally threatened Straw-headed Bulbul (Pycnonotus zeylanicus) populations in Singapore: a last straw for the species?” published in Bird Conservation International is available to download for free until 9th March 2017.

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Peregrine falcon dustbath at Singapore building


This video is called Peregrine Falcon checking out a new condo, July 2015, Singapore.

From the Bird Ecology Study Group in Singapore about this:

In July 2015 Wong Weng Fai photographed a Peregrine Falcon (Falco peregrinus) having a dust-bath on the balcony floor of a yet to be completed apartment in a high-rise building.

Many birds keep their feathers in good condition by taking dust-bath LINK. They lie on the dusty ground and moves vigorously about to get the dirt particles onto their feathers. This helps to get rid of ectoparasites as well as stale secretions from their oil glands.

In the case of this falcon, it found a quiet spot in this uncompleted high-rise building.

The presence of sand particles as a result of building activities and the absence of workers in the unit made this an ideal site for its “bath’. It would not be long before the building would be completed and no opportunity for the peregrine to return. Maybe the photographer would then have an opportunity to document other birds taking shower baths?

Other methods of keeping their feathers in top condition include water bath LINK, preening LINK and anting LINK.

Butterfly of the Month in Singapore, July 2015


This video is called Moulting of a Pandita sinope caterpillar to the 4th instar.

From the Butterflies of Singapore blog:

Butterfly of the Month – July 2015

The Colonel (Pandita sinope sinope)

We have just edged past the halfway mark of the year 2015. A relatively quiet month so far, compared to the more tumultuous preceding months. The summer heat is upon us as Singapore‘s outdoor ambient temperatures move into the 30’s – and made worse by the high humidity. On my short business trip to Delhi and Ranchi in India at the end of last month, I experienced even higher temperatures, although fortunately, the monsoon rains have just started there.

ButterflyCircle members had an enjoyable weekend at the Festival of Biodiversity 2015 at the end of June. More forthcoming community projects with NParks are on the cards, with the NParks Butterfly Count project in September. A challenging project, considering that it involves the general community and sightings of butterfly species in urban parks have to be recorded and counted. Unlike birds, sighting and identifying butterflies requires a bit more experience and training. It will be a good platform to learn how best to deal with field surveys with beginners. …

Let’s leave the worldly woes for awhile as we introduce our Butterfly of the Month for July 2015 – the Colonel (Pandita sinope sinope). This Nymphalidae is one of many species in the family that has been christened with military names. In my article on this blog some time back, I gave some possible reasons how this came to be.

The Colonel is a mid-sized orange butterfly that may be considered moderately rare. However, it is quite local in distribution and often observed in the vicinity of its caterpillar host plants. Sporting an average wingspan of about 50mm, it is not an unusually large butterfly, and may be confused, when in flight, with several other orange-coloured butterflies.

The Colonel is a bright orange above, with the fore and hindwing bases shaded with brown streaks. The outer half of both the fore and hindwings is a prominent brown post-discal band and three dark submarginal lines. The underside is similarly marked, but lighter, with the basal wing area a greenish-grey.

The butterfly is skittish and active and flies with rapid beats of its wings and glides in a manner that is quite consistent with many related species in the sub-family Limenitidinae. Often it may be encountered at the ripened fruits of the Singapore Rhododendron (Melastoma malabathricum), on which it feeds greedily. In the early morning hours, it may be encountered gliding amongst the shrubbery and settling to sunbathe with its wings fully opened.

It is a forest butterfly, and rarely observed in urban parks and gardens. At times, it takes on a territorial behaviour, returning repeatedly to a few favourite perches after flying around to explore its environment. When feeding, it also tends to move its wings often and is very alert. Any threatening movement by an observer will quickly spook it off to the treetops.

The complete life history of the Colonel can be found on this blog article. The host plant on which the species has been successfully bred in Singapore is Uncaria. It has also been bred in Malaysia on another plant – Nauclea subdita also from the Rubiaceae family.

Brown land crab back in Singapore after 77 years


A female brown land crab specimen was found in a drain on St John's Island in Singapore by a Tropical Marine Science Institute scientist. PHOTO: COMPREHENSIVE MARINE BIODIVERSITY SURVEY

From the Straits Times in Singapore:

Land crab sighted in Singapore after seven decades

July 18, 2015, 5:00 am SGT

Return of brown land crab last seen in 1938 linked to efforts to protect the environment

Carolyn Khew

After an absence of over 70 years, the brown land crab has clawed its way back onto our shores.

A female specimen – about 10cm from pincer to pincer – was spotted earlier this month sitting on a mound of leaf litter in a small drain on St John’s Island.

The last time this crab was seen here was in 1938, in Paya Lebar, said crab expert Peter Ng.

“It has never been seen since, and is regarded as locally extinct,” said Professor Ng, chief of the Lee Kong Chian Natural History Museum at the National University of Singapore (NUS). “So to see the crab again on St John’s Island is wonderful. The crab has either been hiding there for decades, or has returned to Singapore after a long hiatus! The important thing is, it is no longer extinct.”

Also known by its scientific name Discoplax hirtipes, the crab has a wide distribution in South-east Asia and the western Pacific. It comes from the same family as the Christmas Island red crab.

Prof Ng said the brown land crab lives in coastal habitats, digging burrows under rocks and vegetation, but can sometimes be found many kilometres inland. However, he added, they reproduce by releasing larvae into the open sea. This is different from freshwater crabs, which have large eggs and hatch into miniature versions of the adult.

Assistant Professor Darren Yeo from the NUS department of biological sciences said that as the species frequents coastal areas and needs to return to the sea to spawn, its appearance after more than 70 years shows that efforts to protect coastal and marine environments are worthwhile.

“This also reminds us that species thought to be locally extinct but still occurring in the surrounding region may possibly have a chance to make a return,” he said.

As the crab was an “incidental find”, the first thing to do would be to see if this was a one-off record or if there are more on St John’s Island, or other parts of Singapore, he said. “We should probably also consider if this ‘re-discovery’ could be attributed to increased sampling effort or increased general awareness of our local fauna and of unusual sightings, and missing it previously was because the persisting or surviving population was very small and in isolated areas.”

Tropical Marine Science Institute (TMSI) senior research fellow Tan Koh Siang, who made the find, said the crab had attracted the curiosity of many TMSI staff, who had taken photos of it. “We collected the crab by coaxing it into a paper bag and sent (Prof Ng) a photograph on e-mail,” said Dr Tan.

He added: “I did what any zoologist would have done on seeing something out of the blue!”

The crab was featured recently at the opening of the new Sisters’ Islands Marine Park Public Gallery, and has since been returned to the museum.

TMSI deputy director Serena Teo said: “This is an important taxonomic record. Prof Ng and his team may also want to examine it more closely and take DNA samples to check.”