whimlews @ Semakau South - 08Feb2016

I was expecting to see some waders within the mangrove inlet at Semakau South but there was only 1 common redshank and 1 whimlew (that is what you get when you cannot tell a whimbrel from a eurasian or far eastern curlew). 

I had initially thought this was a curlew due to the length of its decurved bill. However, it has the distinctive dark crown stripes on top of its head which seems to be indicative of a whimbrel. There also seemed to be a dark eye stripe which whimbrels usually have.  

It was all alone within the mangrove inlet walking along the sandbank during the low tide. It soon got dive bombed by a collared kingfisher and it took off flying behind a group of mangrove trees but it soon reappeared to land further along the outgoing stream. I was thinking that it was possible that this was the same curlew i had seen a week earlier on 24Jan2016 at the Northern Semakau shore. (Now, I'm not sure whether that earlier ID was correct if this was indeed the same bird). The bird soon flew off and disappeared beyond the coastal forest.

lone 'whimlew' @ semakau south - 08Feb2016 from SgBeachBum on Vimeo.

I thought that it would be the last whimlew i would see that afternoon but i soon spotted two more out on the intertidal sandy mudflats. These two kept somewhat close to each other as they moved along the shallow pools looking for crabs and shrimp. So are these eurasian curlews or whimbrels?

a pair of 'whimlews' @ semakau south - 08Feb2016 from SgBeachBum on Vimeo.

Here are some links to help you sort out or confuse you further in the quest to tell the curlews apart from the whimbrels :-
Here are some weblinks which try to distinguish between the two birds :
http://www.planetofbirds.com/the-slender-billed-curlew-last-seen-in-the-previous-century
http://www.bto.org/about-birds/bird-id/bto-bird-id-curlew-and-whimbrel
https://www.youtube.com/watch?v=vt8ZK8fI3W8
https://photographyandbirds.wordpress.com/identifying-waders/
http://hubpages.com/animals/whimbrelvscurlew
http://www.nemesisbird.com/birding/bird-sightings/whimbrel-and-long-billed-curlew-comparison-cibola-nwr-az/
http://singaporebirds.blogspot.sg/2012/06/sandpipers-and-allies.html
https://www.theguardian.com/science/punctuated-equilibrium/2011/sep/18/4
https://www.youtube.com/watch?v=pOXpHnZIq8o


https://en.wikipedia.org/wiki/Eurasian_curlewhttp://www.oiseaux-birds.com/card-eurasian-curlew.htmlhttp://eol.org/pages/1049389/detailshttp://www.birdlife.org/datazone/species/factsheet/22693190http://www.birdfieldguide.co.uk/Curlew.html
https://en.wikipedia.org/wiki/Whimbrelhttp://www.oiseaux-birds.com/card-whimbrel.htmlhttp://www.birdlife.org/datazone/species/factsheet/22693178http://www.birdfieldguide.co.uk/Whimbrel.html

And a recent earlier clip showing a eurasian curlew amongst a bunch of whimbrels at the SBWR :

http://sgbeachbum.blogspot.sg/2015/09/eurasian-curlew-swallows-stone-sbwr.html

More about SBWR :
https://www.nparks.gov.sg/sbwr
https://en.wikipedia.org/wiki/Sungei_Buloh_Wetland_Reserve

And Pulau Semakau :
https://en.wikipedia.org/wiki/Pulau_Semakau
http://www.wildsingapore.com/places/semakau.htm

wintering grey plovers @ Semakau South - 08Feb2016

The receding afternoon tide exposed quite a fair bit of the long sandy Southern Intertidal mudflat shore at Pulau Semakau.   The resident grey herons were out at various puddles picking out small fish which were soon to be trapped as the water drained away from the intertidal zone.  

There were also four smaller birds walking about on the exposed sandy mudflats. These were a little difficult to identify as they did not fit within the list of usual resident birds. The birds were of the plover family and were light grey with a pale underbelly. They had longish legs and a distinct stocky bill.

They were obviously not one of the smaller plovers. When one of the birds took flight, the black ancillaries (the area below the wings closest to the body - the equivalent of our armpits) could be seen clearly. The bird also showed a white uppertail covert with some faint markings at the fringe. 

A check with some good friends confirmed that these were grey plovers which are winter visitors to Singapore and are seen on the quieter shores around mainland Singapore. 

wintering grey plovers @ semakau south - 08Feb2016 from SgBeachBum on Vimeo.

Find out more about the grey plovers :

http://www.rspb.org.uk/discoverandenjoynature/discoverandlearn/birdguide/name/g/greyplover/index.aspx

http://www.birdlife.org/datazone/species/factsheet/22693749

https://en.wikipedia.org/wiki/Grey_plover

http://www.bto.org/about-birds/bird-id/bto-bird-id-golden-grey-plovers

http://www.wildlifetrusts.org/species/grey-plover

http://nzbirdsonline.org.nz/species/grey-plover

http://www.xeno-canto.org/species/Pluvialis-squatarola
http://www.environment.gov.au/cgi-bin/sprat/public/publicspecies.pl?taxon_id=865#illustrations
http://www.birdfieldguide.co.uk/Grey_Plover.html

lone whimlew @ Semakau North - 24Jan2016

It was a very windy day and there were 4 grey herons, a great-billed heron, one common sandpiper, two white-bellied sea eagles and a brahminy kite at the shore at Pulau Semakau facing Pulau Bukom. However, there was also another visitor...with a long downward curled bill. This was too long for a whimbrel or was it not?

lone whimlew @ Pulau Semakau - 24Jan2016 from SgBeachBum on Vimeo.

This bird seemed to have a longer bill than what a whimbrel would have. However, this BTO clip mentions that the bill length itself is not a good feature to base an ID on as the 'bill length in both species varies with sex and age'. 

It also looked bigger than a whimbrel although it was difficult to give the bird a proper sense of scale as there were no other whimbrels (or other birds) near it on the shore. Some parts of the clip show it to have a rather long neck....longer than what i think a whimbrel would normally have. Its head however had the dark crown stripes which Whimbrels have on top of their heads and also a dark eye stripe. These are more indicative that the bird was a Whimbrel.

Sadly, i was not able to listen to the calls made by this bird as it was quiet during the period of observation.

I'll just call it a "whimlew" until i can get a confirmation from a more experienced birder.

Update 1 : the weight of initial opinion was that this bird is an eurasian curlew.  However, some others have commented that this was a whimbrel. 

Update 2 : after more consideration, due to the prescence of the dark crown stripes on its head, this bird should be a whimbrel.

Here are some weblinks which try to distinguish between the two birds :
http://www.planetofbirds.com/the-slender-billed-curlew-last-seen-in-the-previous-century
http://www.bto.org/about-birds/bird-id/bto-bird-id-curlew-and-whimbrel
https://www.youtube.com/watch?v=vt8ZK8fI3W8
https://photographyandbirds.wordpress.com/identifying-waders/
http://hubpages.com/animals/whimbrelvscurlew
http://www.nemesisbird.com/birding/bird-sightings/whimbrel-and-long-billed-curlew-comparison-cibola-nwr-az/
http://singaporebirds.blogspot.sg/2012/06/sandpipers-and-allies.html
https://www.theguardian.com/science/punctuated-equilibrium/2011/sep/18/4
https://www.youtube.com/watch?v=pOXpHnZIq8o

https://en.wikipedia.org/wiki/Eurasian_curlew
http://www.oiseaux-birds.com/card-eurasian-curlew.html
http://eol.org/pages/1049389/details
http://www.birdlife.org/datazone/species/factsheet/22693190
http://www.birdfieldguide.co.uk/Curlew.html

https://en.wikipedia.org/wiki/Whimbrel
http://www.oiseaux-birds.com/card-whimbrel.html
http://www.birdlife.org/datazone/species/factsheet/22693178
http://www.birdfieldguide.co.uk/Whimbrel.html

And a recent earlier clip showing a eurasian curlew amongst a bunch of whimbrels at the SBWR :

http://sgbeachbum.blogspot.sg/2015/09/eurasian-curlew-swallows-stone-sbwr.html

More about SBWR :
https://www.nparks.gov.sg/sbwr
https://en.wikipedia.org/wiki/Sungei_Buloh_Wetland_Reserve

And Pulau Semakau :
https://en.wikipedia.org/wiki/Pulau_Semakau
http://www.wildsingapore.com/places/semakau.htm

upside down jellyfish @ pulau semakau shore - Aug 2014

The upside down jellyfish is a strange animal that lives most of its life upside down. This one was in a shallow intertidal lagoon and actually looked like a mass of algae at first glance. In fact, this jellyfish does have algae in its arms which it reveals to the sun when upside down. The algae (zooxanthellae) produces food via photosynthesis which it shares with the jellyfish. This explains why the jellyfish is usually found upside down with its arms containing the zooxanthellae exposed to the sun. It can also catch planktonic prey with its arms. This one was about 7cm in diameter.

upside down jellyfish @ pulau semakau - Aug 2014 from SgBeachBum on Vimeo.

Find out more about this unique species of jellyfish :

http://www.wildsingapore.com/wildfacts/cnidaria/others/jellyfish/upsidedown.htm

common seastar, undercover @ semakau - Aug 2014

The Semakau shore has a lot of common sea stars...a lot.  One has to be careful to avoid the sea stars.

Common sea stars have a habit of digging themselves into the sand. From observations over quite a few shore trips, some specimens start to dig in when a light shines on them. Others however do not and continue to stay at the surface above the sand even in bright sunlight. It could be that the stars become conditioned gradually to light and they tend to shy away from 'sudden' exposure to light when already conditioned to a dark environment.

This star did not dig in completely in the time that i've seen other specimens completely cover themselves. Perhaps that it had become somewhat conditioned to the light.

How do sea stars 'see' the light? Do sea stars have eyes?

Find out the answer here :

http://news.nationalgeographic.com/news/2014/01/140107-starfish-sea-star-eyes-coral-reef-ocean-animal-science/

http://marinelife.about.com/od/invertebrates/f/Do-Starfish-Have-Eyes.htm

http://marinelife.about.com/od/invertebrates/tp/seastarfacts.htm

https://www.sciencenews.org/blog/wild-things/finally-evidence-starfish%E2%80%99s-eyes-let-it-see

http://blogs.discovermagazine.com/science-sushi/2014/01/07/sea-stars-see/

http://news.discovery.com/animals/starfish-see-the-world-using-eyes-on-the-tips-of-their-arms-130706.htm

http://www.sciencedaily.com/releases/2013/07/130705101826.htm

common seastar, undercover @ semakau - Aug 2014 from SgBeachBum on Vimeo.

Find out much more about the common sea star here :

http://www.wildsingapore.com/wildfacts/echinodermata/asteroidea/archaster.htm

acorn worm, casting @ semakau - Aug 2014

Now this has to be one of the most interesting and important animals on a shore. Have you often seen spiral piles of sand sitting on the shores? There's usually a small inch-long tube of yellow which seemed to push out the spiral tubes of sand. What's all this about?

The clip shows an acorn worm at work. The first part of the clip is speeded up 4x. And then the regular realtime speed-time insensitive clip follows. Enjoy! (... Let me know if you watch the whole clip without falling asleep. If you have trouble falling asleep, watch the clip! This should cure insomnia.).

These worms swallow up mud, sand and detritus below the surface and poop (or 'cast') out the sand and mud minus some detritus which is absorbs as the sand passes through it. They can be likened to earthworms and help to churn the top layers of sand and mud.

acorn worm, casting @ semakau - Aug 2014 from SgBeachBum on Vimeo.

Find out more about this amazing ubiquitous shore creature....without which our shores will be so much more.... solid and compacted.

http://www.wildsingapore.com/wildfacts/worm/enteropneusta/enteropneusta.htm

http://en.wikipedia.org/wiki/Acorn_worm

http://www.mbari.org/news/homepage/2011/enteropneusts/enteropneusts.html

http://www.ucmp.berkeley.edu/chordata/hemichordata.html

http://www.mesa.edu.au/marine_worms/marine_worms05.asp

http://cronodon.com/BioTech/Hemichordates.html

semakau seagrass lagoon @ 01Feb2014

Went on a short boat ride looking for oil from the recent ship collisions.
(see Link 1, 2)

On the way to Semakau, ...

Bukom's southern seawall seems to have some dark banding indicative of an oil-spill. The brown spots could be some other localised spill. Wonder what could have caused those spots.

The bad news is that Semakau's northern shore may have had some exposure to some of the oil-spill. There was a distinct dark line on the seawall. 

Whilst the others in the recce went to explore the Northern shore and Terumbu Semakau, I went Westwards along the seagrass lagoon.

The good news is that it looks like Semakau's seagrass lagoon was clear of oil. The seagrass lagoon and shore were 'normal'. No oil seen on the inter-tidal area, shore or on the fringing mangrove trees. That is a good sign.

'Normal' however means a whole lot of trash on the high shore line. Lots of plastic items which had floated in with the tides over many many years still line the shore. 

note the styrofoam box high in the tree

a 3 foot long fluorescent light bulb

bundles of rope

an SPC oil drum

a plastic road barrier

a huge piece of blue plastic sheeting

an old sofa

one of the gazillion mineral water cups and water bottles

a large prawn feed bag

This was a balloon stuck high up on a mangrove tree.

We really should take better care of our marine environment.

At the southern end of the seagrass lagoon, lots was happening.

This chap had harvested quite a few large mud crabs from the mangrove inlet.

Another few were harvesting shells from the inter-tidal zone whilst another laid out a long driftnet on the inter-tidal zone.

 A ciggarette butt was care-less-ly dropped in the water.

A quick chat with one of them showed them to be contractors at the landfill site out to gather a quick seafood dinner. 

They promptly agreed to return their haul to the lagoon and to recover the driftnet that was being laid out.

 No fan clam soup tonight.

The men soon left in their vehicles parked atop the service road. 

The mud-crabs were however not released. Looks like crab curry tonight.

 

There were two long driftnets long abandoned at the South-Western tip of the seagrass lagoon. These looked like they had been on the inter-tidal for some time. (There was a third driftnet at the Northern part of the seagrass lagoon.) 

 A super long driftnet attached at one end to the replanted mangrove trees and the other to a rock on the inter-tidal zone. 

These carpet anemones will not last very long with the driftnet filaments draped over them.

These driftnets will need some tedious work to remove them and the various organisms that become stuck in them.

That's a task for another day with more time. 

It soon got dark during the long walk back up the lagoon.

Can you name the following ?

Have a look here for help.

Good night Semakau!

See these links for news on the collisions and oil-spills. (Link 1, 2, 3, 4, 5)

Read about what the others saw :

Peiyan's Kusu Island check : Link

Peiyan's Semakau check : Link

Wonderful Creation's check : Link

Singapore Reef Watch's check : Link

WildSingapore's 4 Feb 2014 summary update on the oilspills : Link

NEA 4 Feb 2014 Advisory : Link 

Otter at Semakau!

Had heard of reports of there being an otter sighted in the Semakau mangroves some months ago and had also seen what looked like otter footprints on the beach but had never seen other signs of it.

Fortunately, a recent visitor (YYJ) to Semakau was lucky enough to not only see the otter but she manage to take a picture of it carrying off it's dinner of a snake!



This could mean that Semakau's mangroves and seagrass lagoon are indeed capable of sustaining larger mammals and hopefully eventually a resident family of otters.

However, perhaps there should be a formal restriction on long nets used by visiting fishermen especially in the seagrass lagoon and areas surrounding Semakau. This would help ensure that the otter does not end up being entangled in the nets which are often left abandoned or discarded irresponsibly.

other sightings of an otter at Semakau :-
http://rmbr.nus.edu.sg/news/index.php?entry=/education/20051203-public_semakau.txt
http://www.wildsingapore.com/news/20070506/070511-2.htm
http://www.wildsingapore.com.sg/wildfilms/blog/archive/2006_04_01_wildfilms_archive.html

Yellow-Lipped Sea Krait @ Semakau 06Nov2009

Yellow-Lipped Sea Krait @ Semakau 06Nov2009 from BeachBum on Vimeo.

This beautiful but highly venomous sea krait (Laticauda colubrina) was out hunting amongst the coral rubble once the night sky was dark enough. It was about 75cm long and was swimming actively in the shallow water.

Notice that the sea krait uses it's tongue underwater just like how land snakes do. Interesting how the tongue taste function is used both on land as well as under the water. Note also the laterally compressed tail which allows for great swimming. Since it does not have gills, nor does it have the ability to absorb oxygen from the water through its skin, the snake has to breathe air from the water surface. The snake was observed lifting its snout above the water surface about every 3 minutes.

More Info about this snake :
http://www.wildsingapore.com/wildfacts/vertebrates/snakes/laticauda.htm
http://www.wildasia.org/main.cfm/support/Yellow-lipped_Sea_Krait
http://en.wikipedia.org/wiki/Laticauda_colubrina
http://wildshores.blogspot.com/2009/08/two-headed-yellow-lipped-sea-krait.html

Other blogs about the trip :-
http://wildshores.blogspot.com/2009/11/snakes-in-fish-feeding-frenzy.html
http://wildshores.blogspot.com/2009/11/success-at-semakau-giant-clams-and-more.html
http://psychedelic-nature.blogspot.com/2009/11/id026-boring-giant-clam.html
http://sgn090608.blogspot.com/2009/11/091106-semakau.html

noble volute @ semakau 08Feb2009

noble volute @ semakau 08Feb2009 from BeachBum on Vimeo.

This small noble volute (about 8cm long) was cruising in a seagrass patch containing :
Enhalus : http://www.wildsingapore.com/wildfacts/plants/seagrass/enhalus.htm
Thalassia : http://www.wildsingapore.com/wildfacts/plants/seagrass/thalassia.htm
Syringodium : http://www.wildsingapore.com/wildfacts/plants/seagrass/syringodium.htm

Being a predator, it was looking for prey (other snails) using it's siphon or snout to trace chemical trails left behind by other snails.

Status : Vulnerable. So DO NOT remove it from the shore if you come across one!

Find out more about noble volutes here :
http://www.wildsingapore.com/wildfacts/mollusca/gastropoda/volutidae/nobilis.htm

fanworm 4 @ semakau 08Feb2009

fanworm 4 @ semakau 08Feb2009 from BeachBum on Vimeo.

clip showing yet another fanworm.
This one was in a good location on a mound of sand with its tube sticking out. The current of water flowing by was strong and yet the 'fan' did not retreat into the tube. I tried to cause a retraction by dripping water right above the fan. After a few tries, towards the 1.21 min mark, the fan was retracted in a split microsecond! Amazing reflex action!

Read more about Fanworms at :
http://www.wildsingapore.com/wildfacts/worm/polychaeta/sabellidae.htm

strange anemone @ terumbu raya 09Feb2009

strange anemone @ terumbu raya 09Feb2009 from BeachBum on Vimeo.
Came across this strange anemone (most of them are new to me anyway!).
Appearing black from far away...it was actually closer to a very dark reddish brown from up close.

my foot, being in the wrong place, was responsible for mucking up the water coming into the pool which contained the anemone...this is evident from all the particles floating into the scene. I decided to abandon the anemone for the time being and looked around for something to mark the spot. The good thing about submerged reefs like Terumbu Raya is that floating rubbish tends to float on with each high tide. There was almost nothing to be seen except for a coke can which had got stuck in the mud. I emptied it and placed in on a nearby rock and moved on.

Later Stephen came by and said he had seen the anemone too but that it had disappreared into a hole. When I went back to the coke can...the anemone was nowhere to be seen....all that remained was a hole in the sand. And it was about time to leave the terumbu.

More about this anemone here :
http://wildshores.blogspot.com/2009/02/strange-anemone-from-pulau-semakau.html

Turns out that this is Actinostephanus haeckeli and it is "known from the western rim of the Pacific."

Cool! that Singapore has them too!

More about the trip here :
http://wildshores.blogspot.com/2009/02/reefs-of-raya.html
http://wildshores.blogspot.com/2009/02/maiden-trip-to-terumbu-raya.html

fanworm 3 @ semakau 08Feb2009

fanworm 3 @ semakau 08Feb2009 from BeachBum on Vimeo.
This fanworm also does a split second retreat into the tube. Amazing speed!

fanworm 2 @ semakau 08Feb2009

fanworm 2 @ semakau 08Feb2009 from BeachBum on Vimeo.
Watch out for the split second moment when the 'feathers' retreat into the tube. Faster than your blink!

fanworm 1 @ semakau 07Feb2009

fanworm 1 @ semakau 07Feb2009 from BeachBum on Vimeo.
Fanworms are one of the more pretty animals on the reef.
They are sensitive to sudden disturbances and will retract into their tubes as the slightest hint of trouble.
Read more about them at :
http://www.wildsingapore.com/wildfacts/worm/polychaeta/sabellidae.htm

Close Encounters with a Large Fish @ Semakau 07Feb2009

Close Encounters with a Large Fish @ Semakau 07Feb2009 from BeachBum on Vimeo.

Was alerted to this large fish (measured at 90cm by the Site 1 Seagrassers) caught in the shallows by the Team Seagrassers at Site 1 on Semakau. It must have been caught in the shallows because of a 200m long net stretching across most of the seagrass lagoon. It was gasping for air when I got to it. Careful about the sharp protusions just beyond the tail section, I used a plastic bag floating nearby to grab hold of the tail and lifted the fish cautiously. It was too weak to splash about and I lifted it clear of the water looking for a deeper pool. The low tide had drained the whole seagrass area of most of the water and I had to carry the fish towards the Sargassum boundary close to the edge of the reef. Once in the water again, it took about a minute to swim upright before heading in the right direction...out to sea.

What kind of fish was it? The info learnt from the Leaf Monkey Fishy Workshop pointed to the direction that this was a fast swimming fish due to it's V tail and narrow horizontal profile. Probably one of the 'Jacks'.

Short Clip on the long long net which prevented the fish from heading out to sea.

200m+ long net from BeachBum on Vimeo.

Short Clip on tiny juvenile fish which got stuck on the long net.

(if the small fish get caught too...then where are the bigger fish going to come from in future?)

tiny juvenile fish stuck in long net @ semakau 07Feb2009 from BeachBum on Vimeo.