Rare reptiles find home; Hatchlings: Extinct in its native habitat, the tiny Egyptian tortoise is making a comeback at the Baltimore Zoo.


For the diminutive Egyptian tortoise, the Reptile House at the Baltimore Zoo may now be a more congenial place than back home on Egypt's Mediterranean coast.

Herders, pet traders, farmers and developers have wiped out the species in Egypt, and it is vanishing in Libya and Israel. In this decade it has become the most endangered of the world's turtles, and one of the most endangered animals of any species.

But in Baltimore, the zoo crew has turned a closet full of plastic tubs and electric lights into one of the most successful nonprofit Egyptian tortoise nurseries in the world.

Since their first breeding success in 1994, the tortoises have produced 37 hatchlings. Nine have arrived this year, and four more eggs are incubating.

"It's very satisfying for us here to be successfully breeding an endangered species, and hopefully saving the tortoises from extinction," said Karen St. John, a member of the curatorial staff.

"The fact they're taking the time and space and energy to breed this endangered species is a feather in their cap," said David S. Lee of the Tortoise Reserve, a tortoise conservation organization based in North Carolina.

The Egyptian tortoise is the world's smallest tortoise species. They are tall enough to seem nearly spherical, but the adult females grow only to softball-size dimensions, while the males top out at the size of baseballs. They can live 60 years or more. Some at the zoo are more than 30 years old.

This year's nine hatchlings -- Thursday, Cairo, Moses, Rooney, Leroy, Squishy, Pee Wee, Tick and Arthur -- were lined up last week in their terrarium, basking under a brilliant spotlight.

They range in size from pingpong ball (Thursday, 3 1/2 months old) to large marble (Arthur, 3 weeks). Their tan shell plates are edged in dark brown.

The breeding adults were across the aisle in three large sand-filled tubs, awaiting their next meal of kale, collard greens, carrots and squash. Nine more adults and juveniles were on display in the Reptile House's public gallery.

For millions of years, their small size helped the Egyptian tortoises survive in a harsh environment. But in this century, it made them the quarry of pet traders.

Unlike other reptiles and tortoises that soon outgrow an urban apartment, "these guys stay small, so it's something people can work with in a confined area," said Terri Turnbull, a commercial breeder and dealer in Bainbridge, Ohio.

From 1992 through 1996 -- the year after international commerce in Egyptian tortoises was finally banned under the Convention on International Trade in Endangered Species (CITES) -- more than 2,000 were imported into the United States alone.

"And probably for every one brought in, three or four of them died," said Lee.

The CITES ban has had an effect. Since 1995 "there have been very few seizures in consumer countries," said Bruce Weissgold, CITES policy specialist at the U.S. Fish and Wildlife Service. There have been only a few seizures in countries where the tortoises survive in the wild.

But the ban may have come too late. A 1994 survey of the tortoises' range in Egypt found no living specimens and little habitat capable of supporting them.

Survivors are likely in coastal areas of Libya and Israel. But urban development, grazing and agriculture threaten them there, too.

Second breeding site

The first captive-breeding successes came at the Jersey Wildlife Trust Preserve in the United Kingdom.

The Baltimore Zoo was the second, St. John said, and "we are the first to have yearly breeding."

Some of the Baltimore Zoo's animals are on breeding loans to zoos in Denver and Tennessee. "I believe some of them have had successes, too," she said.

Commercial reptile breeders are also doing well, although there is no data on how many animals they produce.

"We've been very successful," Turnbull said. "I've never had any difficulty at all." She began breeding the Egyptian tortoises eight years ago, and now produces about 40 a year for sale.

FDA sales prohibition

One kink in the trade, Turnbull said, has been a U.S. Food and Drug Administration prohibition on the domestic sale of turtles smaller than 4 inches long. The ban is an effort to protect children, who might put small turtles in their mouths and be infected with salmonella bacteria.

"The problem with Egyptian tortoises is they always fall under that category," Turnbull said. Only some females get that big.

And there's a loophole. The small turtles can be sold for educational or scientific purposes, but few dealers check. Turnbull said she makes her customers sign a paper stating their purpose before she will sell to them. But "you can only go on a person's word," she said.

The CITES ban has boosted prices. When imported animals were available, they sold for about $100, Turnbull said. "Now they're $300 to $400 for captive-bred babies the size of a nickel." Older animals might sell for $400 to $500.

St. John said the secret to breeding Egyptian tortoises is mimicking the seasonal light and temperature cycles of the North African desert.

The zoo's breeding tubs are kept at 80 to 85 degrees, and light cycles are timed at 12 to 13 hours a day in the spring and summer breeding season, and 10 to 11 hours in the fall and winter.

After the tortoises mate, the females lay one or two eggs and bury them in the sand. The zoo staff digs them up and moves them to an incubator.

A push for more males

There, the pale, translucent eggs no bigger than a large grape rest in beds of vermiculite for 60 to 90 days until they hatch. Incubator temperatures are critical. Temperatures at the extreme ends of the safe range typically produce more males.

"But we've reduced [temperatures] slightly," St. John said. "We would like to produce more males because they're rarer in the population right now."

It's not clear whether captive breeding will ever lead to reintroduction of the Egyptian tortoises to their native range. "To release captive-bred animals into the wild could introduce diseases into the wild population, or genetic anomalies we're not aware of," St. John said. "In the future, who knows? If they're completely extinct [in the wild] it may become feasible."

Reintroduction seems unlikely. Their habitat is being destroyed by development, over-grazing and farming. Human encroachment has brought with it dogs, ravens and other predators whose numbers are increasing.

For now, zoo breeding will have to suffice, St. John said. "We have to do what we can to preserve the diversity of species on the planet."

Pub Date: 9/06/99

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