These images of the Common Kingfisher (Alcedo atthis) was taken by KM Sim on 29th December 2012 at the Japanese Garden in Jurong.
Note that the kingfisher is in its comfort mode, first scratching its head directly by raising its right foot from under its wing. This method of scratching is typical of terrestrial birds – mainly to preen its head feathers. Usually preening is done with the bill. See HERE in the case of the Red-breasted Parakeet (Psittacula alexandri). On the other hand, with aboreal birds, they scratch with the its foot extended over the wing, as in the Barn Swallow (Hirundo rustica) HERE.
Comfort activities also involve stretching it wings, as shown above.
The Common Kingfisher was also documented manipulating a large fish that it caught earlier (above and below). Kingfishers need to be careful to swallow the fish head first. Swallowing tail first will result in the spines of the fish causing damage to the bird, sometimes even leading to death. Here, the bird is carefully manipulating the fish so that it enters its buccal cavity head first.