I made a late afternoon visit back to the wader pool at Kubang Semang. This time, there only four Ruffs and no stints in evidence, but the Ruffs were closer than previously, giving me a good opportunity to study the differences between the one male and three females present.
Males (below) are easiest to tell from females (above) when the two can be directly compared, since the male is about 20% larger than the female. However, I was interested to see whether there are other features which make them sexable when seen singly. According to Chandler’s Shorebirds of the Northern Hemisphere, males have a proportionally shorter bill, longer legs and smaller head than females. I would add to that a longer neck, a more angular head profile, and generally more ungainly proportions.
Here’s a female preening.
I’m always fascinated by Yellow Wagtails, and in particular, wondering whether I would pick out a Western. I reckon my chances are increased by trying to familiarize myself with the bewildering variety of plumages of Eastern races. This one had dark ear coverts and an obvious white chin, and a supercilium that seemed intermediate between macronyx and tschutschensis. Another Eastern Yellow variation!