This documentation of a Black-capped Kingfisher (Halcyon pileata) catching a fiddler crab was made in the Mai Po marshes of Hongkong (above). Jianzhong Liu a.k.a Jz first posted the images in NaturePixels.org in March 2008
The Black-capped Kingfisher breeds in the Indian subcontinent, Myanmar, Indochina and Korea. It winters in many parts of Southeast Asia. In Singapore as well as in Hongkong, it is a rare winter visitor and passage migrant, although Hongkong sees an occasional bird during summer.
The bird is seen mainly in tidal mudflats feeding on crustaceans. Along the coasts it takes mainly crabs and fish. Elsewhere, it may take beetles, grasshoppers, crickets, bees and wasps. Occasionally it takes frogs and lizards.
The kingfisher usually perches on a convenient location to survey the surroundings. From here it flies out to take the prey. In this particular case, it hovered above the crab for a moment, its wings flapping up and down, in order to maintain its position (above, below left).
It suddenly drew its wings upwards and plunged down into the mud (above right). At the same time when it landed, it expertly picked up the crab in its bill (below). Then, with a great effort, it brought its wings downwards to provide lift and flew off with its prize between its bill (top). Normally, just before plunging, its nictitating membrane will cover its eyes to provide protection. However, this has not been captured in the images.
The crab is a smallish calling crab, also known as fiddler crab, recognised by its distinctively asymmetric claws. According to Prof Peter KL Ng, the crab expert at the National University of Singapore, it is possibly Uca vocans or Uca lactea. The crab in the images appears to be a male as it has an over-sized claw that was waved in the air in a futile attempt at dissuading the kingfisher’s advance. This large claw is also waved around during courtship to attract females.
Why the crab decided to stand its ground and not scuttle into its burrow is a puzzle, considering the huge threat looming above.
1. Carey, G.J., Chalmers, M.L., Diskin, D.A., Kennerley, P.R., Leader, P.J., Leven, M.R., Lewthwaite, R.W., Melville, D.S., Turnbull, M. & Young, L. (2001). The avifauna of Hong Kong. Hong Kong Bird Watching Society.
2. Wells, D.R. (1999). The birds of the Thai-Malay Peninsular. Vol. I, Non-passerines. Academic Press, London.
3. Woodall, P.F. (2001). Family Alcedinidae (Kingfishers). Pp. 130-249 in: del Hoyo, J., Elliott, A. & Sargatal, J. eds. (2001). Handbook of the birds of the world. Vol. 6. Mousebirds to Hornbills. Barcelona: Lynx Editions.
All images by Jianzhong Liu.
This post is a cooperative effort between www.naturepixels.org and BESG to bring the study of bird behaviour through photography to a wider audience.