Two elephants play at a natural watering hole and salt lick near the Treetops Hotel inside the Aberdare National Park about 150 kilometres north east of Nairobi, capital of Kenya, Aug. 29, 2012. (Xinhua/Wang Chaowen)

An elephant uses its trunk to search for food at a natural watering hole and salt lick near the Treetops Hotel inside the Aberdare National Park, about 150 kilometres north east of Nairobi, capital of Kenya, Aug. 29, 2012. (Xinhua/Ding Haitao)

An elephant and two buffaloes drink at a natural watering hole and salt lick near the Treetops Hotel inside the Aberdare National Park, about 150 kilometres north east of Nairobi, capital of Kenya, Aug. 29, 2012. (Xinhua/Wang Chaowen)

An elephant searches for food at a natural watering hole and salt lick near the Treetops Hotel inside the Aberdare National Park, about 150 kilometres north east of Nairobi, capital of Kenya, Aug. 29, 2012. (Xinhua/Wang Chaowen)

An elephant uses its trunk to drink at a natural watering hole and salt lick near the Treetops Hotel inside the Aberdare National Park, about 150 kilometres north east of Nairobi, capital of Kenya, Aug. 29, 2012. (Xinhua/Wang Chaowen)

An elephant and several buffaloes search for food at a natural watering hole and salt lick near the Treetops Hotel inside the Aberdare National Park, about 150 kilometres north east of Nairobi, capital of Kenya, Aug. 29, 2012. (Xinhua/Ding Haitao)

Elephants come to a natural watering hole and salt lick for food and drink near the Treetops Hotel, inside the Aberdare National Park, about 150 kilometres north east of Nairobi, capital of Kenya, Aug. 29, 2012. (Xinhua/Ding Haitao)

An elephant uses its trunk to search for food at a natural watering hole and salt lick near the Treetops Hotel inside the Aberdare National Park, about 150 kilometres north east of Nairobi, capital of Kenya, Aug. 29, 2012. (Xinhua/Wang Chaowen)

Elephants come to a natural watering hole and salt lick for food and drink near the Treetops Hotel inside the Aberdare National Park, about 150 kilometres north east of Nairobi, capital of Kenya, Aug. 29, 2012. (Xinhua/Ding Haitao)