August 19, 2005—Hundreds of "petrified hippos," as conservationist J. Michael Fay calls them, throng what's left of a river in Tanzania's Katavi National Park in October of last year. Released this week, the aerial photo is evidence of the increasing human "footprint" that Fay witnessed during the "Megaflyover"—his seven-month aerial survey of Africa (see map).

Drained by farmers for irrigation, the Katuma River can now barely sustain the local hippopotamuses, which need its cooling waters to survive the dry season. "These guys just sit there all day, hoping for the sun to go down," Fay said. The photo shows them "just barely hanging on."

"I later heard that the rains came a few weeks later, just in time to save most of them," Fay said.

A joint project of the National Geographic Society and the Wildlife Conservation Society, the 60,000-mile (100,000-kilometer) series of flights left Fay "more impressed than depressed."

Still, in Africa "the management of the natural resource base is not what it could be," Fay said. "Looking at that base and how it can support human life, and how we can better manage the natural resources, is definitely where we need to go."

—Ted Chamberlain

See more photos and a video clip from the Megaflyover.

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