Gulls galore...

First of all, please do not let my title of this post give you a wrong impression. Gulls are uncommon here in Peninsula Malaysia. In fact, most of them are extremely rare. Of the handful of species that occur in our waters, only the Brown-headed Gull can be considered to be a regular winter visitor. It is locally common at only a few sites and the Bagan Belat coastline in mainland Penang is one of them. Numbering up to 40 strong at times, this species is no stranger to the birders here including yours truly. Now, the second commonest gull around is the Black-headed Gull. Both species are remarkably similar-looking especially in non-breeding plumage but there is one major difference - the latter is a rare migrant.

I was truly excited when Hor Kee found a juvenile Black-headed Gull among the flock of Brown-headed Gulls at the Bagan Belat coastline recently. I had no photographic evidence of my sighting of this species in the past at this locality as well and this individual, that seemed to have settled in quite comfortably here for the winter, presented me with an opportunity to make things right. It took a couple of trips before I finally managed to get close enough for a reasonably good photo session. Upon further scrutiny, I found not one but two juvenile Black-headed Gulls among the flock of Brown-headed Gulls. Christmas came early for me this year!   

The size is probably the most distinct difference for two species at rest but it is only helpful when both are present. When seeking confirmation of the identification of the celebrity gulls later back home, Dave pointed out that if the outermost primaries are completely white below, it is the Black-headed Gull. And that made life a whole lot easier…

Midway through my observation, one of the Black-headed Gulls drifted away from the flock and when for a swim…

In flight, the Black-headed Gull is distinguishable from the adult Brown-headed Gull (left) by the absence of the "mirrors" enclosed within the dark primaries. 

Another adult Brown-headed Gull in flight showing off its signature underwing pattern…

Juvenile Brown-headed Gulls are even more similar to the Black-headed Gulls and they even have the same dark-coloured irises as the latter instead of the pale irises of the adult birds – another characteristic that is used to tell adult gulls apart.

The "mirrors" are also absent from juvenile Brown-headed Gulls. So, it boils down to the outermost primaries again to differentiate young gulls. 

Here is a comparison shot of the juveniles of both species. Young Brown-headed Gull (left) can be lighter built at times and look so similar to the Black-headed Gull that they could have been passed off as siblings. Isn't gull identification such a joy...

This Black-headed Gull making sure I do not put it down as a juvenile Brown-headed Gull by flashing its completely white outermost primaries...

When the initial thrill started to wear off, I diverted my attention to the commoner Brown-headed Gulls. I must admit the adults are quite attractive even in non-breeding plumage. 

The Brown-headed Gulls sensing that the limelight is now on them started to put on a really good show for a very contented waterbird addict. I spend a whole lot of my time scanning the coastlines of Penang for birds and to me, this is about as good as it gets when it comes to gulls.