Ostriches swim!
 Q:
Can ostriches swim? Lisa, Ridley Township, Pennsylvania
The consensus is ostriches can swim, even though they don't seem the type. Photo courtesy of the Melbourne Zoo and Wikipedia.
A: An ostrich, his black wings flailing for balance, sought the scant
shelter of trapped debris against a fence, as Hurricane Katrina's winds lessened
in southeastern Louisiana. Water lapped against the fence, rising twelve feet in thirty minutes.
At first,
the ostrich ran against the moving current but even his nine-foot height proved
short. Two toes on one foot flicked the inundated ground, the other foot
found only water. The ostrich floated, low in the
water, his 250-pound (115-kg) mass buoyed by light, hollow, bird bones.
Kicking off the submerged fence, he stretched his neck forward, and slowly
swam toward higher ground. He passed two men in a trawler, also paddling toward safety.
One man with poor eyesight peered at the apparition. "It looks like the
Loch Ness Monster!"
"It's an ostrich," Meyers, his buddy, said.
Can ostriches swim? In August 2005, George Lee and his roommate,
Michael Meyers, saw one swim by as they paddled toward the highway near the
small town of Poydras, southeast of New Orleans, according to an account
published in the Galveston County Daily News.
I retold the story, with a
little poetic license.
Rheas (another large flightless bird related to the ostrich) swim routinely. "When swimming, very little of their
bodies appear above water; their necks are extended a little forward, and their
progress is slow," Charles Darwin wrote in The Voyage of the Beagle.
I asked ostrich ranchers and zookeepers for help
answering this question. Answers flooded back: ostriches can swim.
The cincher came from
Sharon Dewar and bird curator
Michael Mace of the San
Diego Zoo. Mace found a South African Dispatch Online article that reports wild ostriches swimming
in the sea.
Almost at the tip of South
Africa, near Cape Town, a fisherman saw two female ostriches on tiny Schaapen Island,
and alerted park staff at a nearby bird sanctuary on the
mainland. A day later, the two birds
waded back into the sea, and fought their way across strong cross currents for
twenty minutes to the mainland. Park staff monitored their progress in a
patrol boat.
Apparently, ostriches swim by "using the same motion pattern of the legs as
they do when running, however, not very efficiently," conjectures biologist
Christoffer Johansson, a
professor at the Lunds University in Sweden who studies the hydrodynamics of
swimming birds. Johansson says if
they're buoyant enough to keep their heads above water, "swimming is not very
difficult."
Ostrich farmers provided more evidence. Here are a few of many helpful
replies:
-
"They can swim
across a pond," says
Rooster Cogburn of the
Rooster Cogburn Ostrich Ranch in Arizona.
-
"Yes they can [swim]; on hot days they
love going into water to cool down," says
Dougie Bester of Cango Ostrich Farm,
nine miles (14 km)
outside of Oudtshoorn in South Africa.
- During
excessive rains, a farmer said ostrich pens
on her farm filled with water, and the ostriches swam, "like swans", across a pond to dry ground." emails Dianna Westmoreland
of the American Ostrich Association.
- Donna Dernbach of
Golden Dreams Ranch in Wisconsin emailed about a friend's ostriches, "They go into the water and swim to the
other side [of a pond]. All the farmer could see was their necks and heads."
Further Reading:
For one man, Katrina was one storm too many, Galveston County Daily News,
Sep. 4, 2005.
Ostriches observed swimming in the sea, Daily Dispatch Online, East London,
South Africa, Nov. 27, 1998
Hollow leg bones of birds and T. Rex, Museum of Natural Sciences, North
Carolina
L.C. Johansson and R.Ĺ.
Norberg (2003). Delta-wing function of webbed feet gives hydrodynamic lift for
swimming propulsion in birds.
Nature 423(6944): 65-68.
A picture of a swimming or, possibly, wading ostrich, found by Bob Jenkins
of the San Francisco Zoo and taken by John Entwistle, Jr.
The Voyage of the Beagle by Charles Darwin, 1839.
Ostrich description, Stulany Ostrich Farm, Slovakia
(Answered April 23, 2007)
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