Photographer Wee Hiang Her captured a couple of shots of a Yellow-vented Bulbul (Pycnonotus goiavier) feeding its chick with a batch of tiny snails and published the images in Avian Watch Asia’s website (left).
These freshwater or terrestrial molluscs, probably Melanoides sp., are usually found around drains, ponds and even moist soils in urban areas. The snails appear empty, and if so, then the adult is feeding its chicks calcium.
An earlier post document a male Oriental Pied Hornbill (Anthracoceros albirostris) bringing to the female sealed inside her nesting cavity pieces of snail shells. This is not unusual as such behaviour in hornbills has also been reported in Malaysia
There are enough reports of birds consuming shells as well as other materials for their supply of calcium in the literature. Whether it is for the female during her long period of confined incubation or for the recently hatched chicks, the birds need this element for bone formation and egg laying.
At the same time the shells are useful as grit in the gizzard of the bird, assisting in the grinding of the food. Our field ornithologist Wang Luan Keng says that there were always pieces of shells in the gizzard whenever she dissected this organ.
Credit: Wee Hiang Her (images), Wang Luan Keng (comment).