What's A Lake Doing In The Middle Of The Desert?

Play associated audio

One place you don't expect to see waves lapping against the shore is in the middle of a desert. But that's exactly what's happening deep inside the United Arab Emirates, where a recently formed lake is nestled into the sand dunes, and a new ecosystem is emerging.

Drive through the desert in the United Arab Emirates, and all you see mile after mile are red, rolling dunes. Maybe some occasional trees or shrubs, but otherwise a dry, red sandscape.

And then, suddenly, a bright blue spot comes into view. It must be a mirage, you think. But it's not.

The water's edge comes right up to the sand, the wet and the dry, kissing. The wind whips across the blue water's surface, pushing it into a light chop. And wispy reeds in the center of the lake flutter in the breeze.

Human-Made Origins

Dave Clark, a hydrologist with the U.S. Geological Survey working in the United Arab Emirates, says this lake emerged from the sand a few years ago.

"You see local families out here and they're all just enthralled," Clark says. "It's water in the desert, so everybody's pleased. But it's definitely water that's had a human touch to it. People have had their hand in this water, maybe literally."

Here's how this lake got here: A desalination plant right on the coast pulls in saltwater from the Persian Gulf and makes that water drinkable and usable. The water is then pumped 150 miles inland to the city of Al Ain. The residents there drink it up, bathe with it and then flush it down their drains.

"It goes to the sewage treatment plant, and they treat it, and they bring it back into town. And they water the parks and the gardens and things like that, and that percolates down into the groundwater," Clark says.

And then it ends up in the desert, a short distance from Al Ain, by percolating back up from the ground. This water's clean. But still, it comes as a shock to some in the desert.

"Just because the sand dunes look on the surface to be fairly barren doesn't mean that they are. They are full of life," says Brigitte Howarth, an ecologist at Zayed University in Dubai.

Howarth studies insects that evolved in the harsh, arid conditions and worries that some of them aren't faring so well in this part of the desert that's suddenly underwater. Like the midas fly, which she spotted for the first time in October 2010.

"All of a sudden, this fly started to dip its abdomen into the sand. And so, it's about an inch deep in the sand, and it's egg-laying," Howarth says.

The midas flies rely on dry, loose sand to lay their eggs. But the lake is flooding more and more of the sand. Howarth hadn't yet spotted any midas flies this year, and she's concerned about the lake's effect on their habitat.

"For them, the encroachment is in fact a death sentence," Howarth says.

Rolling The Dice

The wind blows the sand off the top layer of the dunes to create a kind of granular fog in the air. But underneath that shifting surface, the world is more stable. So if the dunes are dry enough and warm enough to allow midas fly eggs to hatch, Howarth knows that a raft of other organisms — like insects, plants and reptiles — will probably be in good shape too.

Howarth trains her eye on the lake. It has risen 35 feet in the last year alone. She's concerned that this new source of water, and the development pressures of a growing human population, don't bode well for the dunes.

"With every species that we lose, it's like rolling the dice. The whole ecosystem could crash down," Howarth says.

But Clark, with the U.S. Geological Survey, says he's not so worried about the desert ecosystem. He says the lake is tiny compared to the vast amount of desert in this part of the world.

"If I look through the binoculars, there's, like, seven different kinds of herons. There's greater cormorants. There's ferruginous ducks, which are another very rare worldwide species," Clark says. "There's about 15 of them out here."

This year, three types of birds bred at this lake. They've never been able to breed before in the United Arab Emirates. But this lake, and the others like it, have changed all that.

"Every year, we find two or three or four or five birds that have never been seen before in the UAE. So it's one of the few places in the world that the number of birds is actually increasing, instead of decreasing," Clark says.

There are fish appearing in these lakes as well. Fish eggs cling to the feet and legs of the herons. So as the birds shuttle between old and new lakes, the eggs fall off and hatch. That's how you get fish in a desert.

Copyright 2012 National Public Radio. To see more, visit http://www.npr.org/.


Writer James Alan McPherson, Winner Of Pulitzer, MacArthur And Guggenheim, Dies At 72

McPherson, the first African-American to win the Pulitzer Prize for fiction, has died at 72. His work explored the intersection of white and black lives with deftness, subtlety and wry humor.

Oyster Archaeology: Ancient Trash Holds Clues To Sustainable Harvesting

Modern-day oyster populations in the Chesapeake are dwindling, but a multi-millennia archaeological survey shows that wasn't always the case. Native Americans harvested the shellfish sustainably.
WAMU 88.5

Your Turn: Ronald Reagan's Shooter, Freddie Gray Verdicts And More

Have opinions about the Democratic National Convention, or the verdicts from the Freddie Gray cases? It's your turn to talk.


Trump's Cyber Comments Rouse The Democrats

As they bolster their case that Hillary Clinton is ready to be commander in chief, Democrats are seizing on Donald Trump's comments seemingly encouraging Russia to use cyber-espionage against Clinton.

Leave a Comment

Help keep the conversation civil. Please refer to our Terms of Use and Code of Conduct before posting your comments.