What are these Asian openbill storks feeding on, in Rajasthan

From the archive record

These storks seem to be eating molluscs that they are managing to locate at the edge of Jawai Bandh Dam, Rajasthan. Three Asian openbill storks are busy feeding inside a water body. They are checking on prey they are getting underwater. The storks with white plumage and black wings exhibit a distinctive gap between the arched upper mandible and recurved lower mandible in adults. The juveniles develop this feature later in life. Their main diet are molluscs. A flock of open bills sit atop a tree grooming themselves. This footage is part of the broadcast stock footage archive of Wilderness Films India Ltd., the largest collection of HD imagery from South Asia. The collection comprises of 150, 000+ hours of high quality broadcast imagery, mostly shot on 4K, 200 fps slow motion, Full HD, HDCAM