The very first 'proper' field guide I ever had, when I was about 10 years old, was the first edition of the Hamlyn Guide to the Birds of Britain and Europe. On browsing through this book to check out possible rarities I might one day find, I remember reading the description of Sooty Tern, and finding out that the call is supposedly
'ker-wacky-wack'! Ever since that day I've wanted to see a Sooty Tern, and especially, hear one give its unforgettable-sounding call.
But I get ahead of myself! Today I was on my own on the boat as my usual fellow-conspirators were otherwise dutifully occupied.
Today was my first June trip ever, so there was a sense of heading out into the unknown - which could be great...or a total waste of time!
Birds were few and far between, but there were a few Bridled Terns about in the golden early morning light.
And one on the other side of the boat! The bird is perched on a piece of polystyrene junk. This is so commonplace on the sea that it has become a kind of microhabitat. I've never seen Bridled Terns swimming in the sea; when they aren't flying they are always perched on some piece of floating debris - usually made of polystyrene.
As I was scanning the few terns flying past I was stunned to see this fella coming toward me. Immediately obviously broader-winged and with more 'tummy' than a Bridled, the diamond-shaped forehead patch and blackish upperparts identified it as a Sooty Tern! Wells mentions only one previous record for Peninsular Malaysia, in 1973. It was by now just after 7.30am, I had my 'lifer' and I wondered if the day's excitement had already peaked - in which case it would be a long day!As it happened, I needn't have worried.
This Parasitic Jaeger kept its distance [EDIT: Actually a Long-tailed Jaeger, see here], as did a shearwater which was probably Short-tailed, but at a range at which I couldn't certainly eliminate Sooty Shearwater.Once we put the net out, it quickly became clear that the earlier Sooty Tern was not a one-off.
Here are a couple of shots showing Sooty and Bridled more or less alongside each other. Sooties are very noticeably larger, and the size difference is probably emphasized by their more portly body, broader-based wings and stiffer, less languid flight.
Adult Bridled (above) and Sooty (below). Apart from the obvious difference in upperpart colour, Bridled can be differentiated by the white forehead extending over the eye as an eyebrow, whereas on Sooty, the white is restricted to the forehead only. This is quite an important feature to note, as sometimes Bridled can look quite dark above. The other supposedly diagnostic feature is the white nuchal collar on Bridled, which separates the dark cap from the mantle. On Sooty, the black of the cap joins the dark mantle - according to the books I've read (but see below!)
From below you can get an idea of what a skinny creature a Bridled Tern is compared to Sooty! Notice also that the underside of the primaries of Bridled are pale with dark tips, but all black on Sooty.
Another view showing the stocky physique of a Sooty.
In the strong sunlight, one of the easiest ways to pick out an adult Sooty at a distance was a silvery sheen on the fresh primaries, which looked almost whitish at times.
And I did get to hear them call! Not really 'ker-wacky-wack' to my ears, but a very distinctive di- or trisyllabic note which sounded like a child's squeaky toy!
Most books I've read insist that one diagnostic feature of Sooty is that it lacks the white nuchal collar which Bridled shows. However, not for the first time, I realized that the birds don't read the books! This bird had a rather broad white nuchal collar, divided by only the thinnest of pale grey lines, which would surely be imperceptible to field observation. 
Another view of presumably the same bird.
Most birds conformed to the field guides though, to varying degrees!
This must be an adult in non-breeding plumage. The silvery-grey new primaries contrast with the darker unmoulted outer ones.
Juvenile Sooties are really interesting - and I can imagine easily being mystified if I saw one flying distantly offshore. At times they can look like a jaeger, a shearwater or a large petrel, or even a miniature frigatebird!
Even the darkest birds show pale underwing coverts, belly and vent.
From above they look all dark.This bird seems to be very young, with almost all fresh juvenile feathers, and just a few new mantle feathers coming through.
This one is a bit more advanced, with what looks like a fresh mantle and mostly new median coverts. The new coverts are 1st winter plumage, which does not look as dark as a full adult.
Doing a quick petrel impression! The youngest birds had all chocolate brown underparts.
These appear to be replaced by paler feathers as the bird goes through its first moult.
I would guess this bird is in complete first winter plumage.It wasn't easy to count the Sooty Terns among a wheeling flock of over 300 Bridled, but I guessed there were at least 15 birds.
Looking back on my blog, I reckon that
this bird, which at the time I identified as a dark Bridled, was more likely a Sooty.
I was interrupted in my meditations on Sooty Terns by the crew shouting my name. I looked down over the side of the boat and saw this!
The first thing I noticed about this shearwater, apart from the fact that it seemed intent on climbing up the net and into the boat, was that it looked very different from the Short-tailed Shearwaters we were seeing a few weeks ago. For a start it had pink feet, as well as rather long wings and a long graduated tail. The bill was much longer than Short-tailed, the head was a different shape, and it clearly wasn't in moult, as all the Short-tailed had been! I realized that I was looking at a Wedge-tailed Shearwater, a species I hadn't seen since 2006, and my first in Malaysia.
I got a nice view of the distinctive tail shape as the bird chased after fish scraps being thrown to it by the crew as they hauled in the net.
Looking down from the upper deck, I was more or less looking at the top of the bird.
It used its tail as a rudder and its wings for forward thrust when diving for fish.
Full-frame, zoomed out to about 150mm!
This bird was either hungry, greedy or possibly both, and was totally focused on getting as much food as possible!
Well, stories about unrestrained greed usually don't end well! Just after I took the last picture there was an almighty splash, as one of the crew jumped on top of the bird. He emerged clutching it and passed it up through several pairs of hands, eventually, to me. I was distraught at these developments, but they clearly thought they were doing me a great favour, so I did my best to be tactful. They wanted to slit the bird's throat, and it took me some minutes to succeed in persuading them to let me release it. No doubt, my intention was as strange to them as theirs was abhorrent to me! 
Once they had agreed, I let the bird go and it flew off and settled at a more discrete distance, looking very bedraggled but apparently none the worse for wear, bearing in mind that it had had a 65kg human land on top of it moments before.Later there were a few awkward moments, but I avoided being 'released' over the side to follow the shearwater, and I talked to them about what had happened.
Do they always catch the birds when they come close to the boat? "Yes"
What do they do with them? "Take them home and eat them for dinner."
Do they taste good? "No, they're full of bones and their meat is tough."
So why do you kill them? A phlegmatic shrug - "It's something to do."
An older crew member told me that in the 1970s rafts of 20-30 birds would attend the nets. Now they come in ones and twos. Honestly, I wonder how any survive, given the Dodo-like disposition of these birds and the number of boats out casting their nets daily.
Anyway, having made my feelings plain on the matter, we managed to maintain good relationships on board, and they all said they thought the shearwater had been 'very lucky'!
At the end of the day, as we headed back to port, my sharp-eyed crew member friend, Harom, spotted a jaeger sat on yet another piece of polystyrene.
I recognized the bird as one I had seen earlier in the distance harrying terns, and, with tongue in cheek, identified it as a Parasitic Jaeger, based on three facts:
1. It was stood on polystyrene - Poms and Long-tailed I've seen always sit in the water.
2. It allowed close approach. Poms are really shy and to a lesser extent, so are Long-tailed
3. It had been chasing terns. I've not seen Poms chase terns
For the purists who insist on actual evidence based on the structure and plumage of the bird, it has a pale patch on the forehead at the base of the bill, pointed central tail feathers and lacks pale bases to the greater underprimary coverts, which all rule out Pomarine, and it is much too stocky for Long-tailed.
Even though I'd seen a lifer that says 'ker-wacky-wack' and had a Wedge-tailed Shearwater so close it bit me, I still reckon a good old Arctic Skua (sorry, "Parasitic Jaeger") in low sunlight over a blue sea takes a bit of beating!
