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Bird List Revision for November 2018

The fourth revision of the Singapore Bird List for 2018 is now available at our website. The downloadable list (in Excel format) is available HERE.

There are two new species added in this revision.

Large Woodshrike
A female Large Woodshrike was seen at Jelutong Tower on the morning of 22 October 2018. This species was reported as a former resident of Singapore until at least the 1940s in the Bukit Timah area. There were additional unconfirmed records in 1970 from Changi, unfortunately without supporting evidence. It is highly likely the species have been extirpated in Singapore for a long time, and the newly recorded bird is a non-breeding visitor to the island. Perhaps it is a post-breeding dispersant or a wandering bird.

Large Woodshrike at Jelutong Tower. Photo credit: Francis Yap

Eurasian Skylark
A lone juvenile Eurasian Skylark was seen along the bund of Pandan Reservoir on 3 November 2018. Just a day before, a similar juvenile was recorded at Mantatani Island in Sabah, Malaysia.

Its inclusion to the Singapore list is not a given though. Various species of larks are sold and bought in Singapore. Although there is currently no evidence of juvenile Eurasian Skylarks being offered for sale, the possibility cannot be ruled out. However, the concurrent sighting in Mantatani does strengthen the case of the bird being a genuine vagrant. Furthermore, the seen bird’s feathers seemed to exhibit no abnormal wear which would indicate captivity. On balance, the evidence suggest that particular skylark is a good candidate for inclusion to the list.

Eurasian Skylark at Pandan Reservoir. Photo credit: Francis Yap

Other changes in the Singapore Bird List in accordance with IOC World Bird List version 8.2 are as follows:

  1. Lesser Cuckooshrike has been reassigned to genus Lalage following Jønsson et al, 2010.
  2. Pallas’s Grasshopper Warbler has been reassigned to genus Helopsaltes following Alström et al, 2018.
  3. Moved Black-winged Flycatcher-shrike and Large Woodshrike to Family Vangidae.
  4. Resequenced Campephagidae (Cuckooshrikes) and Phylloscopidae (Leaf Warblers and allies) families.

First breeding record of the Barred Eagle-Owl in Singapore Island

The Barred Eagle-Owl (Bubo sumatranus) is a relatively small eagle-owl that is found from southern Myanmar, Thailand, Malaysia, Singapore and southwards to Indonesia. Its natural habitat is subtropical or tropical moist lowland rainforests. It has also been reported in secondary growth, abandoned orchards, oil palm plantations and wooded gardens, showing its adaptability towards human encroachments. According to Wells, the Malaysian owls are in fact relatively unafraid of people.

In Singapore, it is considered a rare resident species with breeding records only at Pulau Ubin (Ubin Island).

In the main island of Singapore it was once considered an uncommon bird, but believed to have been extirpated since the mid 1920s. It was only in October 1996 that one owl was seen and heard at Bukit Timah Nature Reserve. Subsequently, sporadic sightings were also recorded at MacRitchie Reservoir and Nee Soon Swampforest. Recent sightings were at Bukit Timah Nature Reserve in 2015 and 2016.

On 24th May, 2018, Peter Ding reported a pre-dawn sighting of an adult owl on a tree along the path to Singapore Quarry, next to Fuyong Estate. This was relatively near from what was believed to be its usual haunt at Bukit Timah Nature Reserve. Subsequent follow up search did not manage to locate this owl. However on 7th August, 2018, Peter Ding again sighted and recorded a video of what appeared to be a juvenile Barred Eagle-Owl calling for its parents at the same area. So the search was on again to locate the juvenile and its parents. The other interesting detail to follow up was to confirm the sexual dimorphism in this species as previously documented in Johor by Con Foley et al. Finally with that established, to hopefully determine the sex of the juvenile owl. In order to accomplish all these, clear photos were needed.

At the time of discovery, the juvenile owl was estimated to be 8-10 months old, if the breeding cycle for this family was the same as the Johor birds. It was likely that the juvenile will soon disperse and the adults will start another breeding cycle towards the end of the year. Time was running out to locate it.

Thankfully based on information from Peter, the activity and location of the juvenile were somewhat predictable, and the owl was seen and photographed on 8th, 9th, 15th, 16th and 17th August 2018.

Underparts of the juvenile Barred Eagle-Owl.
Upperparts of the juvenile Barred Eagle-Owl.

In the above photos from 16th August, the juvenile owl is clearly seen to have almost finished moulting into adult-like feathers and features. Only part of the head and ear tufts remain whitish compared to the adults. Also notice that it’s clutching a bunch of leaves and acting like its a prey. The previous day, it was seen attempting to hunt next to a house.

The juvenile on the left (based on facial and ear-tufts colour) and the adult male Barred Eagle-Owls. At this stage, the juvenile is almost full-sized.

In the above photo from the morning of 17th August, the juvenile can be seen with blood-smeared talons, so feeding was just completed, although it’s uncertain whether the food was self-caught or given by the adult. The juvenile was calling before it was found so it’s likely it was looking for its parents. At night, the juvenile was seen flying off with a snake, and again the adult was nearby.

While all these were happening, the adult male had been spotted occasionally in the late evenings coming out of its daytime roost and flying off to the nearby trees to preen and prepare itself before starting its hunt at night. This presented another photo opportunity.

The adult male Barred Eagle-Owl at a perch in the evening. This is a relaxed pose.
The adult male Barred Eagle-Owl on high alert, due to the calls of a family of Racket-tailed Drongos. Notice the elongated body and raised ear tufts.

A video of the adult make in fading light, showing its activity before nightfall. By the end of the video, it was hard to see the bird but it’s in fact becoming more active.

Let’s move on to the identification of the adult male and female owls. It is known that Barred Eagle-Owls pair up and mate for life. So it should be possible to get both of them together in one photo to compare their size and appearance. One can speculate that if they are busy with caring for the juvenile, the chances of them being together side by side should be slimmer. It’s a busy time after all, having to feed a growing owl and teaching it how to fend for itself. On the other hand, if somehow the juvenile has just dispersed, the mating season should start again soon and the adults may spend more couple time together with displays of affection to reaffirm their bond.

Display of affection of the adults Barred Eagle-Owls.
It is the female that initiate the display.
Remnants of feathers from a very recent kill on the talons of the owl. Photobombed by a planthopper.

The two photos below should help to answer the question of the sexual dimorphism of this species.

Front profile of the adult Barred Eagle-Owls. The female on the left and the male is on the right.
Another photo of the pair of adult Barred Eagle-Owls. The male has blood-stained upper mandible.

The differences in appearance between the adult male and female are in broad alignment with what was described in Con’s article. They are summarised below:

Female Male
Larger in size Smaller in size
Distinctly darker face disc Absence of or less distinct face disc
Rufous-brown upper breast patch Less contrasty brown upper breast patch
Spotty and short dark barring on lower belly and breast Thicker more continuous barring on lower belly and breast

This leaves us the question of the sex of the juvenile. A side by side composite photo of the three owls is shown below.

Composite photo of the juvenile, adult female and adult male of Barred Eagle-Owls.

It is clear that the juvenile more closely resemble the adult male in appearance.

As to its whereabouts, it has not been seen for more than 2 weeks as this article is being prepared. Wells mentioned that a juvenile that fledged in April was still with parents in August, but had left by the next breeding attempt in November. The related Eurasian Eagle-Owl (Bubo bubo) juveniles leave their parents between mid-August and mid-November. Settlement places were on average, 46 km away from their birth place. If the same dispersal pattern and distance can be observed in the Barred Eagle-Owls, this would explain the initial arrival of this species from Johor and their subsequent breeding in Singapore. Barred Eagle-Owls are long-lived birds. Wells reported one or a pair at the same location in Kuala Lumpur for a minimum of 14 years. Lets hope the adults stay on and repopulate Singapore with more of their progeny.

Image Gallery

References:

  1. Wells, D.R., 2007, The Birds of the Thai-Malay Peninsula: Vol. 1 – Non-passerines, ISBN 10: 0713674644 ISBN 13: 9780713674644
  2. Wang Luan Keng, Christopher J. Hails, April 2007, An Annotated Checklist of the Birds of Singapore https://lkcnhm.nus.edu.sg/app/uploads/2017/04/s15rbz001-179.pdf
  3. Con Foley, Lau Weng Thor, Lau Jia Sheng, Tan Kok Hui, BirdingASIA, Number 19, June 2013, Breeding Barred Eagle Owl Bubo sumatranus sumatranus in Johor, Malaysia http://confoley.com/barred-eagle-owl/
  4. Aebischer, A., Nyffeler, P. & Arlettaz, R. J Ornithol (2010) 151: 1. Wide-range dispersal in juvenile Eagle Owls (Bubo bubo) across the European Alps calls for transnational conservation programmes https://doi.org/10.1007/s10336-009-0414-2

Bird List Revision for June 2018

The third revision of the Singapore Bird List for 2018 is now available at our website. The downloadable list (in Excel format) is available HERE.

There is one new species added in this revision, the Great Slaty Woodpecker. Previously considered to be extirpated from Singapore, with 2 unconfirmed sightings at Changi in the 1970s. A female woodpecker was photographed at Bukit Timah Nature Reserve on 1 May 2018. The woodpecker was seen again feeding near the summit from 4-6 May 2018. A female (probably the same bird) was photographed at Central Catchment forest (along the pipeline trail) from 11-12 May 2018.

A white-rumped storm-petrel was also observed and photographed at a distance on a pelagic survey on 12 May along Singapore Strait. It is likely to be a Wilson’s Storm Petrel, but because of the distance involved, a conclusive ID cannot be obtained without totally ruling out other white-rumped storm-petrels. Hence the decision to withhold the inclusion of this species into our checklist until further sightings are reported.

Pelagic Bird Survey at the Singapore Strait – 5 May 2018

On 5 May 2018, a boat with 10 birders/bird photographers boarded from Marina Cove, Sentosa and headed towards the eastern part of the Singapore Strait up until closer to coast of Pengerang, Malaysia.

The weather was fine, and we expected we should see a mixture of the usual resident seabirds as well as some spring migrants on passage. Early May should bring us some Swinhoe’s Storm Petrels and Short-tailed Shearwaters. Our hunch proved correct.

The Short-tailed Shearwater is listed as a rare passage migrant for Singapore, and we were glad to see 3 of them in this trip, with a close view of a pair quickly flying past our boat.

Short-tailed Shearwater at Singapore Strait

The Swinhoe’s Storm Petrel is a reliable and common passage migrant at the Singapore Strait. We expected bigger numbers to show up, but we did manage to see at least 6 birds.

Distant shot of Swinhoe’s Storm Petrel at Singapore Strait

What was unexpected was an appearance of a faraway Gull-billed Tern, which was a bonus bird. Unfortunately, it was only seen by a few people on board.

Distant shot of a non-breeding Gull-billed Tern at Singapore Strait

Other terns seen were the usual Black-naped Terns, Lesser Crested Terns, Greater cRested Terns, Little Terns and Bridled Terns.

A pair of Bridled Tern at Singapore Strait
A juvenile Bridled Tern at Singapore Strait
Lesser Crested Tern at Singapore Strait
A Black-naped Tern lit by the warm glow of the morning sun. Photographed at Singapore Strait

Here is the table of the bird count for the trip:

Bird Name Count
Short-tailed Shearwater 3
Swinhoe’s Storm Petrel 6
Bridled Tern 19
Little Tern 30
Gull-billed Tern 1
Black-naped Tern 2
Greater Crested Tern 2
Lesser Crested Tern 29
Tern sp 10
Swiftlets sp 6
Route for the Pelagic Bird Survey – 5 May 2018

Bird List Revision for April 2018

The second revision of the Singapore Bird List for 2018 is now available at our website. The Excel format of the list is available HERE.

There is one new species added in this revision, the Indian Paradise Flycatcher. A single bird was reported by Feroz Fizah at Sungei Buloh Wetland Reserve on 23 March 2018 and seen the following day and week. Once its identity was established, Oliver Tan managed to retrieve from his photo archive an older record at the same location on 2 December 2017. Presumably, the bird was wintering in the vicinity the entire season.

Indian Paradise Flycatcher at Sungei Buloh Wetland Reserve in March 2018

With this addition, our Singapore bird list now stands at 400 species. Eleven years ago in 2007, the Pocket Checklist of the Birds of the Republic of Singapore (2007 revised edition) by Lim Kim Seng listed 364 wild bird species being recorded in the country. Subsequent additions and removals resulted in a net gain of 36 species. In other words, we have had a net increase of 10% in the total number of wild bird species recorded compared to 2007. If current trend continues, we can expect addition of an average of 3 new species a year.

Part of reason for this rapid addition of new species into our list can be explained by advancement in the field of bird taxonomy resulting in splitting of what used to be one species into multiple newer ones. A key example is that in the past, the Blyth’s Paradise Flycatcher, Amur Paradise Flycatcher and the newly included Indian Paradise Flycatcher were once lumped together as a single species, the Asian Paradise Flycatcher.

Another important reason is the increasing number of birders and bird photographers in the field over the past decade. There are simply a lot more people in the field looking for birds these days compared to merely a handful in the past. The relative affordability of camera systems play a big part in the increase of number of bird photographers, and a greater awareness of our environment contribute to more people taking up the hobby as well. These days, our nature reserves, parks and gardens are teeming with people participating in all sorts of outdoor activities (including birding), increasing the odds of finding rare birds in our midst.

Lastly and more speculatively, climate change may have affected bird migratory patterns causing unexpected vagrants to turn up. Three of the vagrants newly included in our checklist, the Booted Warbler, Indian Paradise Flycatcher and Jacobin Cuckoo are migratory birds that normally winter within the Indian subcontinent. It will be interesting to see whether there will be a measurable increase in the frequency in which such vagrants turn up in our tiny island in the future.

Visitor numbers for singaporebirds.com for January 2017 to March 2018.

On a different note, the number of website visitors for the site have steadily increased as seen from the graph above. We are averaging around 600 page views from 130 visitors on a typical day for the month of March 2018. Of which, about 66% of the page views are from Singapore IP addresses, meaning that a large percentage of our visitors are local readers looking for bird information. It seems we are reaching our target audience as intended.

We are glad that there have been sustained interest in this website’s content, despite the recent lack of regular updates. Thank you once again for your continued support!

Bird List Revision for January 2018

The latest revision of the Singapore Bird List is now derived from IOC World Bird List Version 8.1.

Changes are as follow:

  1. Addition: Little Stint– Two birds at Chek Jawa, Pulau Ubin on 21 September 2017 by NParks (David Li, Jacky Soh and Fadhli Ahmad)
  2. Addition: Verditer Flycatcher – A single bird photographed by George Presanis at Dairy Farm Nature Park on 9 October 2017 is the first confirmed record of the species.
  3. Addition: Booted Warbler– Single bird at Kranji Marsh reported on 10 December 2017 by Martin Kennewell and Richard Carden. An earlier sighting on 4 December 2017 of an unidentified warbler by Muhd Fadhil of NParks was subsequently confirmed to be the same bird.
  4. Taxonomic change: The local subspecies of the “purple swamphen” complex (subspecies viridis) is now treated as a subspecies of Grey-headed Swamphen instead of Black-backed Swamphen.
  5. Taxonomic change: Crow-billed Drongo‘s scientific name is now changed to Dicrurus annectens.

The latest list can be found HERE.

Bird List Revision for August 2017

We are pleased to publish the latest revision of the Singapore Bird List to include taxonomic changes based on the latest IOC World Bird List version 7.3.

The changes are:

  1. Replacing Glossy Swiftlet with Plume-toed Swiftlet due to split of the Glossy Swiftlet species complex (Rheindt et al. 2017)
  2. Change of genus name for Garganey and Northern Shoveler from Anas to Spatula (Gonzalez et al. 2009)
  3. Change of genus name for Gadwall and Eurasian Wigeon from Anas to Mareca (Gonzalez et al. 2009)
  4. Family Scolopacidae (sandpipers and snipes) resequenced to follow Gibson and Baker (2012)

The latest list in Excel format can be found HERE.