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Under and Around the Red Sea

Tomb of the Pyramid Builders

Science and the Brain

Oasis of the Ancestors

Saving Storks in the Sinai

Ancient Flutes in Egypt
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SHOW 304: Saving Storks in the Sinai

Twice a year, over 450,000 white storks (Ciconia ciconia) migrate from Europe to southern Africa and back again. The trip is arduous, made more difficult by man-made perils like aircraft, power lines, barbed wire, polluted water and pesticides. FRONTIERS investigates efforts in Israel and Egypt to prevent bird-plane collisions and aid the travel-weary birds.

Activity: Flying on Thermals
Report From the Field: Jeffrey E. Glen, Lawyer/Naturalist Volunteer, Sinai Wildlife Project


It might seem that the storks take the long way to Africa; why don't they fly directly over the Mediterranean? Heavy birds have a hard time staying in the air over large bodies of water. They prefer to soar on thermals, columns of warm, rising air created by the unique geography of the Middle East, which give the birds an easier ride. Flying the longer distance over land requires less work than flying a shorter distance over a large body of water. The birds get a lift on a thermal, making a tight corkscrew and rising in altitude so they glide to the next thermal. Glider pilots, too, take advantage of thermals.


Trace the route followed by the white storks from their summer homes in Western Europe, across the Alps and over Turkey, to Israel and the Sinai, then on to Uganda and South Africa.

After mapping out the migration route on an atlas, calculate the approximate number of miles the storks fly from Alsace to South Africa. Convert the number of miles into kilometers.

Note: The heavy storks conserve energy by gliding instead of actively flying all day. At about 20 to 30 miles per hour, gliding is faster than flying, too.

  • You can see the effect of thermals in either one of these two activities. Although the first activity is done with water, remember that fluids behave similarly, whether liquid or gas (air).

  • Fill a small jar to its rim with very warm water. Add several drops of food coloring. Cover the jar with a layer of plastic wrap and secure with a rubber band. Poke several tiny holes in the plastic wrap. Fill a larger jar about 2/3 full of cold water. Carefully lower the small jar into the larger jar and set it upright on the bottom. Observe and explain how the dye spreads. Compare and contrast your observations with thermals in the air (see following activity). What happens if a small jar of cold water is lowered into a container of warmer water?

  • Enlarge and copy the spiral pattern shown below onto a piece of construction paper. Punch two small holes near the center of the spiral. Cut along the spiral line with scissors. Pass the end of a 30cm length of thread through the hole and knot it. Tie the free end of the thread to a paper clip. Position the paper in different locations (over a light bulb or computer works well). Observe its motion.

  • When you find an active thermal, secure the spiral spinner above the rising air currents with tape. Does the spinner rotate clockwise or counterclockwise? How can you change its design to make it spin in the opposite direction? Will the twisted thread ever interfere with the spinning movement?



Though New Yorker Jeff Glen describes himself as a lawyer/naturalist, he never thought he'd be helping to save European storks while vacationing in the south Sinai. Glen's original reason to visit this remote area of the world had more to do with scuba diving than rescuing imperiled storks, but he soon caught the fervor and decided to do what he could to aid the White Stork Project, started by local businessman Adly el Mestikawy and staffed by veterinarians Susan and Jim Dinsmore.

Glen describes Sharm el Sheikh, a major way station for migrating storks, as the "best of all places I've been to observe wildlife." It also helps that this southern-most point of the Sinai Peninsula offers some of the greatest diving in the world. The underwater treasures lured Glen there in September of 1992. Here in the Red Sea, the reefs are only about nine inches below the surface, enabling divers to walk out and then hit a falloff of 60 to 80 meters. Unfortunately, their shallowness also makes the reefs vulnerable to damage (as depicted in this episode's story on coral reefs).

Glen was surprised to find out that storks are carnivores. "Every day the hotels donate raw chicken parts to feed the storks," he described. "A crew goes to pick up vats of chicken backs and gizzards. The storks are big," he noted, commenting on the bird's 4 1/2-foot wing span, about the same size as a crane or blue heron. When Glen stayed at Sharm el Sheikh, he watched many storks land at the refuge with a variety of injuries. "One bird's beak was totally closed by fishing wire," he recalled. "Susan Dinsmore and some of the military guys had to snip the line."

Back in New York, Glen completed the legal work to set up the Sinai Wildlife Project, Inc., a non-profit organization that he and the Dinsmores hope will assure permanent funding for the White Stork Project. Glen emphasizes that the project has operated on a volunteer and donation-only basis for the past two years; T-shirts, posters, postcards and stickers are now available.

If you're interested, write to: Sinai Wildlife Project, c/o Jeffrey E. Glen, Berwin-Leighton, 135 East 57th St., 11th floor, New York, NY 10022.


Scientific American Frontiers
Fall 1990 to Spring 2000
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