James Spears takes his 1964 German built Amphicar for a drive on Lake Mead in Nevada May 6, 2015. Its a journey many drivers dream of, rather than travelling round a lake simply driving through it. But for James Spears it may be time to make the most of the waters in Lake Mead in Nevada, as water levels are plunging as California struggles to cope with a fourthsuccessive year of droughts. (Photo by Mike Blake/Reuters)

People walk past debris on May 3, 2015 in Bhaktapur, Nepal. A major 7.8 earthquake hit Kathmandu mid-day on Saturday, and was followed by multiple aftershocks that triggered avalanches on Mt. Everest that buried mountain climbers in their base camps. (Photo by David Ramos/Getty Images)

Framed by the setting sun, an American Bison grazes at the Tallgrass Prairie National Preserve on Tuesday, April 28, 2015, near Strong City, Kan. The buffalo herd at Tallgrass is one of the few herds of wild bison left in the United States. (Photo by Travis Heying/The Wichita Eagle via AP Photo)

A farmer uses a GoPro as he takes a picture of his carabao kneeling during the annual Carabao Festival in Pulilan, Bulacan in northern Philippines May 14, 2015. Water buffalos, locally known as carabaos, are led during a parade in the streets of the town to honour its patron saint San isidro Labrador, and carabaos will kneel in front of the church to give thanks for a year-long bountiful harvest. (Photo by Lorgina Minguito/Reuters)

Elaine Vandiver shares a moment with a two-year old alpaca as they touch noses as she washes him at her farm at 1560 Stateline Road Monday, May 11, 2015, in Walla Walla, Wash. (Photo by Michael Lopez/Walla Walla Union-Bulletin via AP Photo)

Burundian refugees gather on the shores of Lake Tanganyika in Kagunga village in Kigoma region in western Tanzania with their belongings, as they wait for MV Liemba to transport them to Kigoma township, May 17, 2015. Burundi's embattled President Pierre Nkurunziza sacked his defense and foreign ministers on Monday, five days after surviving an attempted coup by generals opposed to his bid for a third term in office. (Photo by Thomas Mukoya/Reuters)

A cloud of black smoke billows out the exhaust pipe of John Robertson's diesel dragster as he runs down the track during the 2015 NHRA Kansas Nationals, Friday, May 22, 2015, at Heartland Park in Topeka, Kan. (Photo by Chris Neal/The Topeka Capital-Journal via AP Photo)

In this photo taken on Saturday, May 16, 2015, Snoek fish with salt on them after they were cleaned in Lambert's Bay, South Africa. The boats line up along the jetty, bobbing in the cold south Atlantic waters, bringing in the day's catch in the early afternoon. The long silver snoek fish is one of South Africa's traditional foods, and a main source of income for the town of Lambert's Bay. (Photo by Schalk van Zuydam/AP Photo)