Teluk Air Tawar-Kuala Muda IBA, Penang. 22 August 2013

The jetty that brought such success in the spring now has a ring of mangrove saplings round it that effectively act as a barrier to waders, which are generally paranoid about enclosed spaces.

IMG_4652Common Sandpiper_TAT_220813_IMG_2984Only Common Sandpipers (and occasionally the odd sand plover  or Terek Sandpiper) venture inside the ‘circle’. This one is a juvenile, my first of the season.

Common Sandpiper_TAT_220813_IMG_2986 I try to take a lot of pictures of waders when they are preening, since many feathers are exposed which are normally kept hidden. In this picture, you can see the beautifully fresh edges of the flight feathers, and the ‘anchor-shaped’ subterminal markings on the inner greater coverts. This pattern is common to juveniles of a number of wader species.Common Sandpiper_TAT_220813_IMG_2986'

Even without seeing this kind of detail, juveniles can often be distinguished by their very neat and tidy appearance, an effect caused by the fact that all the feathers are of uniform age.

Common Sandpiper_TAT_220813_IMG_4786Compare this juvenile with the adult below.

Common Sandpiper_TAT_220813_IMG_4819An adult Common Sandpiper in worn breeding plumage.

Greater Sand Plover_TAT_220813_IMG_4798This is the range I was viewing most birds at! I’ve included this shot as it shows a Greater Sand Plover still mostly in breeding plumage. The majority of Greater Sand Plovers complete their post-breeding moult before beginning migration, so it is fairly safe to say that a sand plover showing breeding plumage on southward migration is a Lesser. But nothing is failsafe in birding – there’s always the exception which proves the rule!

Asian Dowitcher_TAT_220813_IMG_4802Also staying outside the mangrove circle were three adult Asian Dowitchers. Dowitchers are among the earlier wader species to arrive on Malaysian shores. In 2009, there were juveniles in Penang by 23 AugustAsian Dowitcher_TAT_220813_IMG_3025

As the tide rose, instead of coming closer, along with almost all the other waders, they flew past my watchpoint to somewhere else tantalizingly out of view!

Only a few Terek Sandpipers stayed behind, chasing crabs. I shot a video of one in action.

Terek Sandpiper hunting. When it catches a crab, it deftly takes the prey by one leg and then shakes it till the leg is removed. Discarding the detachment, it then picks up the crab by another leg and repeats the process until the crab is literally disarmed. It eats the body of the crab, then goes back and retrieves and eats each discarded leg. I’ve watched Whimbrels, Common Sandpipers and Greater Sand Plovers adopt the same approach when swallowing medium or large-sized crabs. I guess a crab could do some damage if it was swallowed with legs still attached.

Here are a few other videos I’ve uploaded recently:

A juvenile Greater Sand Plover, initially with a Common Redshank, then with an adult and three juvenile Lesser Sand Plovers. 15 August 2013.

Juvenile Lesser (left) and Greater Sand Plovers do some synchronized predator avoidance, probably in response to an overflying House Crow. Check out the difference in proportions between the two species.15 August 2013.

A juvenile Greater Sand Plover in a typical crouched, crab-hunting run. I don’t believe Lesser ever does this.13 August 2013.

Advertisements

3 thoughts on “Teluk Air Tawar-Kuala Muda IBA, Penang. 22 August 2013

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s