At 13,000 sq. km, it is the second largest Tanzanian park and the world's largest elephant sanctuary. The park represents a transition zone where eastern and southern African species of fauna and flora overlap. It is the northernmost example of Miombo woodland, common in central Africa and the most southerly protected area in which Grant's gazelle, lesser kudu and striped hyena are found. To be able to see both greater and lesser kudu and roan and sable antelope in the same park is one of the special attractions of Ruaha. In the dry season, the river is an excellent place for observing large numbers of game including lions, leopards, hunting dogs, giraffe, waterbuck, eland and warthogs. Thousands of birds flock to Ruaha on their annual migration from Europe to Asia, and 465 bird species have been sighted in the park. The park's residents include kingfishers, plovers, hornbills, green wood hoopoes, bee-eaters, sunbirds and egrets.