On 1 October 2011, a group of 7 people took their maiden pelagic bird survey trip on a privately chartered boat. Comprising 6 photography enthusiasts and 1 birdwatcher, this group was inspired by the encouraging results of previous Pelagic Bird Surveys on the Singapore Straits organized by NSS and NParks (especially the excellent photos of the pelagics) into making their own survey along the same route.
The group moved off from Sentosa Cove at early pre-dawn hour and proceeded slowly towards the coastal waters of northern Batam after clearing Immigration and Checkpoint Authority (ICA) near Sisters’ Islands.
The group had difficulty identifying the first few birds encountered at the break of dawn over Indonesian waters due to the bad lighting and also choppy waters (a very different shooting environment from the one the photographers were accustomed to). Nonetheless, they just snapped away on instinct at these darkish birds hoping that they may be storm-petrels, jaegers or shearwaters. To everyone’s disappointment, subsequent checks on the blurry images on the cameras’ LCD screens revealed that they were just swifts and swallows.
The lighting got better as the boat loitered around the coastal waters off Northern Batam and the group finally spotted a pair of storm-petrels skimming just above the sea surface, a very different flight pattern from the earlier swifts and swallows. The group, for the rest of the entire trip, relied on this unique flight pattern of the petrels to spot them from afar. Besides the storm-petrels, a couple of terns were also spotted flying overhead.
Micky, who had just mounted his 600mm lens onto the tripod on the upper-deck, managed to obtain a small image which when viewed at 100% resolution, showed the unique upperwing pattern of a Swinhoe’s Storm-Petrel. As the sky brightened up, Wong (GCSpyder) who is using the best camera on board ie the Nikon D3S (though many readers will likely dispute that) also managed to get a better image of the Swinhoe’s.
The first significant flying tern that was encountered was a Whiskered Tern, with a stocky build and a distinctive dark underpart plumage.
The first “floating” bird captured was a lone Bridled Tern balancing on a small piece of wood bobbing up and down on the water surface.
As the boat moved on, another pair of Bridled Terns were spotted floating together on a piece of debris near a lone Aleutian Tern perching on a wooden-plank a stone’s throw away. At least a thousand shots were unleashed upon these terns in the short duration of about 5 minutes.
As the boat journeyed on, the group chanced upon a family of at least 5 dolphins cruising along the sea surface.
Following the encounter with the pod of dolphins, a very obliging Bridled Tern (moulting to non-breeding plummage) was sighted perching on a big white plastic water container. It stayed put for more than 5 minutes at a very close distance which allowed everyone to obtain good shots before taking off – obviously uncomfortable with the undue attention of the many photographers on board the boat.
Besides the occassional fly-by of terns and petrels, nothing else as exciting happened en route to Horsburgh Lighthouse, also known as Pedra Branca and located at the eastern entrance to the Singapore Straits and about 54 km east of Singapore and 14 km from the Malaysian state of Johor.
When the boat arrived at Horsburgh, the group saw five Indonesian boats fishing less than 500 meters from the lighthouse. Just hovering above these fishing boats were about 60-70 terns taking their turns (pun unintended) to dive into the sea. The scene was just amazing.
After having the boat manoeuvered to the most ideal shooting position, the photographers proceeded to shoot their hearts out. It was estimated that over 90% of this flock of feeding terns were Bridled Terns (visually obvious from their darker upperparts) and the rest with lighter upperparts comprised either Black-naped, White-winged and Greater Crested Terns.
It was only much later when Francis was reviewing the photographs he had taken at the lighthouse that he came across images of an unusual-looking tern. Unable to establish the identification of this tern from the guidebook and also not fully convinced that it was a juvenile Bridled Tern, he posted a couple of flight-shots of this tern on NaturePixels (NPX) website to seek experts’ opinion.
Lau Jia Sheng, who was the first to respond, opined that it was a juvenile Sooty Tern. This was subsequently confirmed by Dave Bakewell and, if accepted by the Nature Society of Singapore’s (NSS) Bird Group, it will be the first record of this species in Singapore. This got the whole group excited and they immediately ploughed through their harddisks to check whether they had captured this “first record” bird. Based on all the images reviewed, it appeared that there was only a solitary juvenile Sooty Tern feeding together with the large flock of Bridled Terns at the lighthouse on the late morning of October 1, 2011. The tern with the unusual plumage was initially ID-ed as a Sooty Tern, but subsequent investigation revealed it to be an unusually plumaged Bridled Tern.
Nothing unusual then happened during the voyage back to Singapore from the lighthouse. This was probably because the group had taken a break for lunch and nobody was standing watch! Nevertheless, there was a rather friendly Greater Crested Tern perching on a long wooden plank at around 12:20 pm that kept the group entertained before they break for lunch.
After the lunch break and as the ship approached the waters off Changi (with the Changi Naval Base in sight), a bird which looked very similar to a non-breeding Little Tern was spotted perching on (what else !) a wooden plank at around 1:30 pm.
Shortly thereafter, a total of four other birds were spotted perching on different types of debris – mostly pieces of polystyrene and wood. Thanks to the golden rule adopted by the photographers on board ie “shoot first and find out later”, these five birds were subsequently identified to be Aleutian Terns (one moulting to and the others already in non-breeding plummage) after a thorough review of the shots taken along the Singapore Straits off the coast of Changi.
Lastly, a pair of Swinhoe’s Storm-Petrels was also sighted off the coast of Changi at around 2:10 pm where a record shot was taken by Francis Yap.
Summary of the interesting sightings are appended below:
A) Bridled Terns: 12 were sighted en route from Batam to Horsburgh. Over 60 birds sighted feeding at Horsburgh Lighthouse
B) Aleutian Terns: 7 were sighted en route from Batam to Horsburgh. 5 (1 moulting to and 4 in non-breeding plummage) sighted off the coast of Changi
C) Sooty Tern: A solitary juvenile sighted feeding with a large flock of Bridled Terns at Horsburgh Lighthouse
D) Greater Crested Tern: 5 were sighted en route from Batam to Horsburgh. At least 1 was feeding among the Bridled Terns at Horsburgh Lighthouse. One was sighted in international waters en route from Lighthouse to Singapore and another 3 sighted off Changi.
E) White-winged Tern: 3 were sighted en route from Batam to Horsburgh. 3 were sighted feeding at the lighthouse.
F) Black-naped Tern: 5 were sighted feeding at the lighthouse.
G) Whiskered Tern: One bird were spotted en route from Batam to Horsburgh.
H) Swinhoe’s Storm-Petrel: 26 were sighted during this trip with a pair spotted off the coast of Changi
Map of our route:
The participants would like to thank the following people for helping in our initial planning and organizing of this trip: Colin Poole, Con Foley and Dr Geoffrey Davison of NParks. We would also like to thank Lau Jiasheng and Dave Bakewell for their invaluable help in identifying the various birds photographed during the trip.