Saturday, March 03, 2007

March 2nd, 2007 Tanjung Tokong

Part of a high tide roost made up mainly of Lesser Sand Plovers and Broad-billed Sandpipers.

Happy days are here again! What a change from two weeks ago, which was the last time I visited the site. Lots of waders, and quite a number moulting into their stunning breeding plumage.

It was interesting to see which species were represented - there were significant changes in the relative abundance of species. Broad-billed Sandpiper, which I have usually recorded in single figures, was the second most numerous species present today, whereas there were no Pacific Golden Plovers at all. Here's my full count:

Lesser Sand Plover 948
Greater Sand Plover 43
Kentish Plover 8
Curlew Sandpiper 114
Red-necked Stint 112
Little Stint 1
Broad-billed Sandpiper 463
Terek Sandpiper 1
Ruddy Turnstone 2
Common Sandpiper 1
Common Redshank 390
Marsh Sandpiper 16
Common Greenshank 25
Little Egret 20
Great Egret 7
Little Heron 12
pond heron sp 10

Total 2,173

I experimented with a new way of counting today. I took several pictures of the roost panoramically, then counted the birds on the computer, making allowances for overlap between pictures. This allowed me to make a very accurate count. I also made an estimate of the total number while on the field, and, rather than count each species, made an estimate of the relative abundance of each species as a percentage of the total. When I comapred my computer count with my field estimations, I found that the two matched pretty well.

An example of a count using the computer. To avoid double counting, I marked each bird with a colour-coded dot (Lesser Sand Plover = beige; Greater Sand Plover = orange; Broad-billed Sandpiper = purple; Curlew Sandpiper = yellow; Red-necked Stint = red). Try doing an estimate of the total number of birds in this picture, and of the relative abundance of each species. Then scroll to the bottom of this post to find out how accurate you were!

A Broad-billed Sandpiper incoming! Note the chestnut breeding plumage tertials of several birds. Also, the Greater Sand Plover in the foreground coming into breeding dress.

This Greater Sand Plover really knows how to stand out in a crowd!

Four species here: Greater (next to the bird raising its wings) and Lesser Sand Plover, Broad-billed Sandpiper and Red-necekd Stint.

It was great to catch up with the overwintering Little Stint again today, as I hadn't see it for quite a while. (For a full summary of what I'm basing my identification of this bird on, see January 21st, by scrolling down here.) It seems to be in head moult, as the supercilium is now almost absent behind the eye. I hope it hangs around long enough to acquire some breeding plumage body feathers. Some of the Red-neckeds are already showing extensive brick-red, pale fringed throat feathers.

This isn't the greatest picture but I include it here to show how easy it is to pick out the Little Stint among Red-neckeds at distance. It seems like a stint on stilts, and it's always actively feeding. The Red-neckeds seem much more sluggish feeders.

This picture shows the distinctive small head and round-chested, rather ball-shaped body in comparison with a Red-necked (on the left).

This picture shows the differences in leg and bill length and shape well. Both the tarsus and the tibia seem longer than on Red-necked.

A view of the plumage features (Little Stint on the right). The supercilium now seems rather diffuse and only visible in front of the eye.

Watch this space! Hopefully it'll stay around for a while longer.

[Answer: Total = 143; Lesser Sand Plover = 73; Greater Sand Plover = 4; Broad-billed Sandpiper = 60; Curlew Sandpiper = 2; Red-necked Stint = 4]

No comments: