Confusing Species: Crow-billed Drongo and Square-tailed Drongo Cuckoo

It is not often that two species from different families can be confusing. More so when they share the same common name as in the case of the Crow-billed Drongo Dicrurus annectans and the Squared-tailed Drongo Cuckoo Surniculus lugubris. Both are black and have more or less the same structure as each other.  But look closer and you will find distinctive features in each species to tell them apart. The Crow-billed Drongo is a winter visitor and passage migrant to Singapore while the ST Drongo Cuckoo is a breeding resident with a few visiting during the winter months. If you see one during the summer months, it will be the Squared-tailed Drongo Cuckoo. They are very vocal all over our forests in May during breeding.

First Winter Crow-billed Drongo                         Adult Square-tailed Drongo Cuckoo

From the above photos, the differences are quite easy to pick out. First look, the Square-tailed Drongo Cuckoo has a slimmer look giving it a longish appearance. The Crow-billed Drongo looks broader.

The bill of the Cuckoo is thinner and slightly decurved, typical of all cuckoos, while the Drongo has an unmistakable broad bill from whence its name is derived.

Only the underside of the tail of the Cuckoo has scattered white barrings on it like most cuckoo species while the tail of the Drongo is unmarked.

The last feature is the shape of the tail. The Cuckoo has more or less a square tail sharing the characteristics of all cuckoos while the Drongo has a forked tail flaring outwards quite a bit.

A first winter Crow-billed Drongo on passage was photographed at Bidadari on the 19th of September by Lim Ser Chai. This is the first arrival for this season but stayed for less than 2 days.

 

 

Comparing Rufous-necked Stint and Broad-billed Sandpiper

Last Sunday during the Fall Migration Bird Census, Kim Keang and his group picked up a Broad-billed Sandpiper and a Rufous-necked Stint at the Mandai mudflats. Both were firsts for this migration season. While both waders have distinctive features of its own to tell them apart, they have very similar body structures with the Broad-billed Sandpiper looking like a medium Stint. From a distance it can be hard to separate.

 

This photo was taken at Parit Jawa last September after waiting for some time for both to come close to each other for a comparison shot. Both are in their non-breeding plumage. The Rufous-necked Stint is between 14-16 cm while the Broad-billed Sandpiper is at 16-18 cm in length but the size difference is very marked in the photo.

The upperparts of the Broad-billed Sandpiper is grey all over with darker wing coverts. It is lighter grey for the RNS. Both have prominent white superciliums all the way to the back of the head, but the lateral crown strip of the BBSP gives it a split supercilium look. The length of the bills is the best ID feature to separate them. The BBSP’s bill is longer. Both look straight but the BBSP actually have a slight curve at the tip (not very visible in the photo).

Let hope we get to see and compare them at Sungei Buloh in the coming days.

Ref: A field Guide to Thailand and South-East Asia. Craig Robson. 2000.

Identifying The Terns of Singapore.

We have 12 of Asia’s 26 species of Terns. Two, the Little and Black-naped Terns are resident breeders. The rest are either winter visitors, passage migrants or vagrants. Terns are generally white in color with shades of grey. Identifying them in flight at a distance is challenging. Many of the medium sizes terns look very similar in their non breeding plumage. Juveniles normally have not developed the distinctive features of the adults. One of the best way to tell them apart is a good photo showing the various features. Both sexes are similar. Mostly found flying over inland water bodies or at sea, they do perched by the reservoir edges, kelongs or rocky out crops. Only the Little Terns come inland to breed. We will try to point out some of the simpler identifying features of these terns in the order of sizes. (Reference from Craig Robson). Hope it will help you with the terns during this migration season,

White-winged Terns, ( 20-24 cm),  juvenile on the right.

It is the smaller of the two “Marsh” (Chlidonias) Terns, the other being the Whiskered Tern. It is about the same size as the Lttle Tern but does not have the fork tail. Best ID feature is the “headphones” on both side of the face. It also has a white rump and smaller bill. Prefers inland fresh water bodies like Serangoon reservoir. Skims over the surface to pick up its catch.

 

Little Tern (22-25 cm), breeding on the left and non-breeding on the right.

Black cap and nape during breeding, white from forehead to behind the eyes. Strong yellow bill with black tip and yellow legs. Harder to separate in non breeding plumage. Look for the deep fork tail and long, thick lighter colored bill. Often looks down when flying over water, it plunges straight down to catch its food. Flies near the shore off Changi and Labrador.

 

Whiskered Tern ( 24-28 cm)

Very similar in appearance to the White-winged Tern but larger. Can be separated from White-winged by thicker and longer bill and grey rump. Also lacking the dark patch “headphones” below the eyes which can be hard to tell apart in the field. Also skims along the surface for food. Shares same fresh water habitats with White-winged. Kranji and Serangoon Reservoirs.

Now can you separate these “Marsh” Terns perched on the railings at Kranji Reservoir?

Black-naped Terns ( 30-35 cm)

Medium size, very white in appearance with a dark band from lore to the black of the nape. Long deeply forked tail. Many terns of the same size in their non-breeding plumage have very similar markings, so care need for identification. Small breeding colony in the Straits of Johor.

Aleutian Tern ( 32-34 cm) breeding plumage on the left.

Once thought to be vagrant to our waters, we now know that a small population winters and passes through the Straits of Singapore during the migratory months. Grey upperparts contrast with white rump. In flight, look for the dark trailing edges of the secondaries. White forehead and black from crown to nape during breeding. Often seen resting on floating debris.

Common Tern ( 33-37 cm)

Uncommon winter visitor, this medium tern has long forked tail. The outer edges of the primaries are dark. At rest, the wings and the tail is of the same length. Non breeding plumage: White forehead and black crown and nape. Straits of Singapore and sometimes inshore.

Gull-billed Tern ( 34-37 cm) Breeding plumage left, non-breeding right.

A rare winter visitor and passage migrant, this heavy bodied tern is best identified by its thick black bill. In flight the broad wings are white below with dark outer primaries. Full black cap during breeding. Small black patch on ear coverts during non breeding. Does not plunge from the air. Reported at inshore waters near the coast at old Halus ponds and Serangoon Estuary.

Lesser Crested Tern ( 35-40 cm) 2nd from the right in breeding plumage, rest non breeding.

Best separated from Swift tern by slightly smaller size and orange bill. During breeding, lacks white forehead as the black crown extends from nape to front. The white on its head is more extensive than Swift tern during non breeding. Prefers off shore waters at Straits of Singapore and Johor.

Bridled Tern ( 37-42 cm) breeding.

An uncommon winter visitor, this large tern may have a small breeding population at Horsburgh Lighthouse. Separated from the Aleutian Tern by a total slaty grey upper part including the rump. The white supercilium extends beyond the eyes. Eastern Straits of Singapore near Pedra Branca.

Swift Tern ( 45-49 cm) breeding on the right.

This large tern has a thick slightly decurved yellow bill. It has a black cap, white forehead and a shaggy crest. Easily identified by its size both in flight and perched. Found with Lesser Crested Terns offshore waters of Straits of Singapore and Johor.

Reference: A field Guide to the Waterbirds of Asia. Wild Bird Society of Japan 1993. A field Guide to the Birds of Thailand and South East Asia. Craig Robson 2000. The Avifauna of Singapore. Lim Kim Seng 2009.

Photo Credits: Alan OwYong, Francis Yap and Jimmy Chew.

 

 

 

 

Singapore Straits Pelagic Surveys – New Seabirds Discovered.

Peter Kennerley and Richard Ollington’s 1998 paper on Aleutian Terns ( above by Jimmy Chew) wintering in South East Asia based on sightings of 11 birds in the Straits of Singapore in 1996 prompted the Bird Group to charter a work boat to do a recce trip to find out what other seabirds passed through and wintered at the Straits of Singapore.

Most of our old records of seabirds were from dead specimens collected from the Horsburgh Lighthouse. But due to the high cost and logistics, it took more than a decade before regular pelagic trips were planned.

Pulau Jong a green emerald in the southern straits.    Indo-pacific Dolphins once common.

Colin Poole MD of WCS was the first to organised a series of pelagic trips in the latter months of 2010. This was followed by NParks in December 2010 when they embarked on a year long marine biodiversity survey. The Bird Group supplemented with our Pelagic surveys in May 2012. We completed a total of eight trips.

Sunrise over Southern islands.

The trips start from the Marina at Sentosa at 6 am as we had to clear immigration at the anchorage so that we can cruise outside the port limits. This can take 10 minutes to hours depending on how many ships were waiting for clearance. Great time to view the sunrise over the southern islands.

The boat will head out to the middle of the Straits and then turn East towards Horsburgh Lighthouse, taking care to stay within Singapore waters. The Singapore CBD skyline with the hundreds of ships at the anchorage is quite a sight. First landmark is the beacon off Batam, a very important navigation aid for the Supertankers. Action normally starts around 9 am when we get close the the yellow buoy off Changi. This is where the Swift and Lesser Crested Terns (below left) rest. From here onwards, Swinhoe’s Storm Petrels can be seen on migration during October. Common Terns (below right) also arrived for the winter.

It is here that Con Foley and company photographed the Pomarine and Long-tailed Jaegers in 2010. These were later accepted and added to the Singapore Checklist. Three other new species were also accepted by the Records Committee based on the Bird Group’s Pelagic surveys in 2011 and 2012: The Red-footed Booby in December 2012 and the Short-tailed Shearwater & Heuglin’s Gull in 20 Nov 2011.  Aleutian Terns are usually found resting on floating debris, with their tails pointing up. This was where we had our second record of the Red-necked Phalarope, a wader that can rest at sea.

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As we get nearer to Horsburgh, flocks of Bridled Terns ( above) come into view. They looked grey from the top and roost on the rocky outcrops around the lighthouse. The population can reach a few hundreds at the peak of the migration season. Other uncommon terns that were recorded are the White-winged, Whiskered and Gull-billed Terns mixed with the resident Black-naped and Little Terns.

It will be lunch time by the time we reached Horsburgh Lighthouse. Many ship captains have been waiting for days to see this lighthouse. It means that they will be enjoying shore leave among the bright lights in Singapore soon.. Fishing around the lighthouse is reported to be great as can be seen by the boats from the nearby fishing village. The trip back in the afternoon is normally quiet and most of us will try to catch up on our beauty sleep until someone started shouting ” Terns”.

Will the migrants still winter at Bidadari next year?

Bidadari is just a small patch of woodlands in our concrete jungle. Yet year after year the returning flycatchers are able to find the place after flying thousands of miles from their northern breeding grounds. Not only that they are able to zoom in to the exact tree or perch that they used the previous years. Morten Strange, our professional bird photographer was able to take his famous photo of the Ferruginous Flycatcher at Bukit Timah Nature Reserves by setting up and focusing his remote camera on a stump in the middle of a quiet trail where the flycatcher had been using year after year. Peter Ericsson was able to tell when the Mugimaki Flycatcher will be visiting his garden in Bangkok, almost to the day.

Yesterday Zacc HD photographed the Asian Paradise Flycatcher (above) at Bidadari, the first posted record for the season. As they breed in Central Asia, with resident populations in Indochina, they would normally arrived earlier, in mid July and August. Why are they so late this year?

This morning this female Yellow-rumped Flycatcher ( first reported by Lawrence Cher on 30th August) was seen moving around the same ticket at Bidadari where they usually spent the winter. How do the do this?

Bernd Heinrich wrote in his definitive book “The Homing Instinct” that the birds migrate using the sun in the day and the stars at night. On cloudy days and nights, they can even use magnetic lines to find their way. But this cannot explain how with such a small brain they are able to zoom in to the same spot every year.

The Bird Group conducted several migrants surveys last year using a GPS Tracking App. A google map pin pointing the locations where the migrants were seen was produced. We passed this map to the HDB during one of the meetings to finalise the planning of the site, Lets hope that the migrants will find some of their favorite perches and trees when they return during the next migration.

 

 

 

When is the best time to see Shorebirds at Sungei Buloh?

Shorebirds or waders start making their way south as early as July and most of them would have arrived at their wintering grounds by October. Ten species have so far arrived at Sungei Buloh, the rarest being the lone Asian Dowitcher on 30th August.

The shorebirds stopped over to refuel at the mud flats off the mangroves of Mandai and other shorelines like Seletar dam. Sungei Buloh is the place where they come in to roost when the mud flats at Mandai are covered up by the rising tides.

The Bird Group and Sungei Buloh did a six months monitoring of their movement in 2011/12. We found that they would normally fly in 2 to 3 hours before high tide depending on how high the tides are. They will then leave Sungei Buloh once the mudflats are exposed again for them to feed.  A wader watcher and photographer will have a window of 6 to 7 hours to see them in Sungei Buloh.

Yesterday the late afternoon high tides and the dry pond in front of the main hide brought them close up. The soft light from the setting sun was perfect for photography.

Here are some of the moments recorded at Sungei Buloh yesterday.

This lone Common Redshank moving across the hide, creating the wake effect against the reflection of the setting sun.

There is no disputes on the ID of this Godwit. We found six Godwits busy feeding in the shallow waters at the main pond. I think they can do this because of their longer bills. Sometimes they will stop and start to take a dip and preen. This is the time to keep them in your focus. You get lucky once in a while when they show your their tail with the right pose.

The 200+ Whimbrels were the most active and did several flypasts for us to get some flight shots much to the delight of David Li and Ron Chew at the hide. This is one of the most recognizable waders because of its size and long decurved bills. This could be the same flock that winters in Buloh year after year.

Most of the waders started to have their evening bath round 6 pm. After vigorously shaking their feathers in the shallows they will stand up and flap their wings to dry themselves. This Common Redshank, still in its breeding plumage, adds color to the shot.

Sometimes group photos can be messy. But I think the low and soft light help to give each bird a focus. The Common Redshanks are the most numerous at Sungei Buloh at the moment close to 400. An interesting tract we found during our monitoring was that some of Common Redshanks do not fly out to Mandai to feed during the low tides. Instead they will stay at Buloh, roosting on the mangroves by the side of the ponds or along the Kranji coast. It could be that they can find what they need at Buloh?

We hope that you will be able to time your visit to Sungei Buloh for the best experience and get some great photos.

 

I want a Swinhoe’s Snipe

The snipes are on their way. From the records listed in “The Avifauna of Singapore” (Lim Kim Seng. 2009 ), we can expect the uncommon Pin-tailed and Common Snipes to arrive in the latter part of September. The rare Swinhoe’s Snipe may arrive around the same time but we do not have any records until November.

Early this year, we stalked out grass patches at the Muslim Cemetery, the marshes at the Japanese Gardens and Lorong Halus trying to get a photo of the Swinhoe’s Snipe. The key is to get shots of the tail feathers spread out. This can only happen when they preen, when they are flying or coming in to land. They also have to be facing away from you. A tall order and a daunting task, certainly not for the impatient. Francis Yap in his blog http://fryap.wordpress.com/category/photovideo-technique/detailed step by step instructions on how to get such shots.

While the Common Snipe can be separated in the field from the other two Gallinagos, it is a different story for the Pin-tailed and Swinhoe’s snipes.  Dave Bakewell had devoted a blog on how to tell the differences between all these three snipe species here: http://digdeep1962.wordpress.com/2014/03/24/keep-calm-and-study-snipes-part-2/. It provides a step by step detailed description of all the pertinent features, drawing on the study done by Paul Leader and Geoff Garey.  A worthwhile read.

I will not go through what Dave wrote so well in his blog but to discuss the snipe that wintered at the Muslim Cemetery this February.

From this photo we can tell that it is not a Common Snipe. It is paler and buffy in appearance unlike the brighter and richer plumage of the Common. The pattern of the wing coverts is strongly barred dark and buff. ( Reference from Dave Bakewell’s Blog). But it is not possible to tell if it is a Pin-tailed or Swinhoe’s Snipe from looking at the features here.

The Common Snipe has whitish unbarred underwing coverts. The underwing covert of this snipe is heavily barred, a feature shared by both the Pintail and Swinhoe’s. Again we cannot identified it as a Pintail or Swinhoe’s.

The same snipe was captured preening with the tail feathers spread out. The thin black and white outer tail feathers stood out against the chestnut broader central tail feathers, a diagnostic feature for the Pintail. For a Swinhoe’s the outer feathers can be narrow as well but there should be a few intermediate lighter feathers between the chestnut central feathers and the outer feathers. So we have a confirmed Pin-tailed Snipe for the Big Year tick.

This migrant season, the race is on as to who will get the definitive video or photo of a Swinhoe’s Snipe as the last record we have was in 2005 based on megala field characters of the bird. I want a Swinhoe’s Snipe. Happy sniping all!

Our Avian Visitors, the August Stars

Henry Koh got the ball rolling with a lone Greater Sand Plover at Seletar Dam on 8th. An early star which can be difficult to find and ID.  This was enough to rekindle the Big Year ticking. It stayed for a week or so unlike the 300 + Lesser Sand Plovers, many still in their summer plumage. Those who came later in the month missed it but had the consolation ticking a Common Greenshank, Common Redshank, a few Pacific Golden Plovers and Common Sandpipers – nothing special.

Lesser Sand Plover at Seletar Dam.

Over at Kranji, Kim Seng was delighted to find the Little-ringed Plovers, the Great and Little Egrets wintering near the golf course on the 10th. On the same day, Vincent Lao posted a photo of a cuckoo from Lorong Halus. It was identified as the rare Austral non-breeding visitor Horsfield Bronze Cuckoo, a much sought after lifer for many birders here. Alas, it turned out to be a one day wonder. So was another non-breeding visitor that Roland Yip photographed, the uncommon Brown-streaked Flycatcher, again at Halus on 30th.

The first flycatcher was a worn out Asian Brown seen by Kim Seng at Sime Forest on 21st. I heard that some photographers had the Asian Paradise Flycatchers earlier in the month, but I could not get records to publish here. The Yellow-rumped Flycatcher followed, a female as expected, reported by Lawrence Cher on 30th at Bidadari, our soon to be developed migrant trap.

2013 File photo of Asian Dowitchers at SBWR

The excitement went up a few notches on 30th when Ben Lee posted a photo of an Asian Dowitcher roosting at Sungei Buloh. The Big Yearers all rushed down to the main hide on Sunday 31st hoping to add to their barren month. Alas it gave us all the slip. Luckily the trip was non in vain. Five Black-tailed Godwits turned up together with a Terek Sandpiper, a lone Grey Tattler and one or two Curlew Sandpipers. Most of us added at least three species to our list.

Common Kingfisher at Gardens by the Bay by Shirley Ng.

Rounding up, Shirley Ng presented us with a gorgeous Common Kingfisher from the Gardens by the Bay. She reported seeing two of these beautiful winter visitors, always a favorite among the bird photographers.

More migrants will be turning up in September and everyone will be glad to be back clicking in the field. Keep the post coming and happy birding.