These are large and impressive bovids that never stray far from water. Image taken In Udu Walawe NP, Sri Lanka.
Date: 28 July 2009
Source: Bull Water Buffalo / http://www.flickr.com/photos/rainbirder/4730747705/
Another page: http://en.wikipedia.org/wiki/File:Flickr_-_Rainbirder_-_Bull_Water_Buffalo.jpg
Author: Steve Garvie (http://www.flickr.com/photos/50079771@N08) from Dunfermline, Fife, Scotland
License: This file is licensed under the Creative Commons Attribution-Share Alike 2.0 Generic license.

The wild water buffalo (Bubalus arnee), also called Asian buffalo and Asiatic buffalo, is a large bovine native to Southeast Asia. It is listed as Endangered in the IUCN Red List since 1986, as the remaining population totals less than 4,000, with an estimate of fewer than 2,500 mature individuals. The population decline of at least 50% over the last 24–3 years is projected to continue.

The global population has been estimated at 3,400 individuals, of which 3,100 (91%) live in India, mostly in Assam.

The wild water buffalo represents most likely the ancestor of the domestic water buffalo.