WILDLIFE agent Jesus Bustamante still remembers the night of the iguanas on the Mexican border. Customs officers were examining an auto from Mexico when they discovered a hidden shipment of 20 snakes, 200 iguanas, and 2,000 tarantulas. When an official opened the box of iguanas, they escaped.
``We chased lizards all over the place that night,'' Mr. Bustamante recalls with a chuckle.
Federal agents - always on the lookout for drug runners - have another serious problem along America's southern border. Smugglers are crossing into Texas and other states with growing quantities of endangered wildlife, such as parrots, and illegal animal products, such as turtleskin handbags.
Every year about $700 million worth of wildlife and wildlife products are imported into the United States.
The World Wildlife Fund estimates that one-fourth of those imports are smuggled or transported to the US with false documents. The illegal animal trade deals primarily in four popular items: elephant ivory, live birds (especially parrots), reptile skins, and furs.
``There is a big demand, a growing demand, for these items,'' says Ginette Hemley, director of trafficking for World Wildlife Fund.
Ms. Hemley estimates that $45 million worth of birds and reptile skins illegally cross the Mexican border every year. The US Fish and Wildlife Service also reports a growing problem with smuggled Mexican furs, including bobcat, ring-tail cat, coyote, and raccoon.
``Mexico is a sieve for contraband,'' Ms. Hemley says. ``It is the only country in Latin America that is not a member of the endangered species treaty [the Convention on International Trade in Endangered Species]. So it has become a funnel for illegal birds and skins from all over the world.''
Wildlife experts give this overview of the situation at US borders:
Ivory. Illegal poaching has wiped out half the world's elephants in the past 10 years. In response, Washington banned all imports of ivory in June 1989. Experts say that will help. But some ivory still is being smuggled into the US or mislabeled to get past customs officers.
Furs. Smugglers use isolated parts of the west Texas border, particularly between the town of Van Horn and Big Bend National Park, to bring in substantial quantities of Mexican furs. Smugglers not only violate Mexican law, which forbids export, but also evade US customs duties.
Birds. A bird worth $15 in Mexico might be worth $100 in Los Angeles. Some criminals import endangered species, particularly parrots, through regular channels by improper labeling. Others, hoping to avoid both customs duties and quarantine, smuggle birds over the Mexican border.
The major sources of rare birds are Argentina, Bolivia, and Honduras, though some come from Africa and Southeast Asia. One danger, according to Fish and Wildlife officials: Avoiding quarantine can threaten US poultry flocks with Newcastle's disease.
Reptile skins. Snakeskin shoes, crocodile skin handbags, and other products made from reptiles produce big profits for smugglers. Even experienced border guards sometimes have difficulty distinguishing forbidden skins from those that are legal.
Though federal officials primarily target large-scale smugglers, even innocent tourists can get snared by US laws regarding wildlife.
``You can go just 200 yards from here [into Mexico] and buy beautiful sea-turtle boots,'' says chief customs inspector Ernie Tejerina in Brownsville, Texas.
Turtleskin boots, which might cost $120 in Juarez or Matamoros, Mexico, are as fine as $750 boots made out of alligator leather. They're a great temptation for Americans and Canadians who go south of the border. But turtleskin boots are illegal in the US because the sea turtle is an endangered species.
Hundreds of tourists return from vacations in Mexico wearing fancy new boots made of turtle leather. Some are forced to leave Customs barefooted.
``I still remember one couple,'' Bustamante recalls. ``They came from Tuscon [Arizona] to Juarez [Mexico] for their honeymoon. There she bought him a new pair of sea turtle boots and made him throw his old pair away. She got really angry when we took her husband's boots - argued with me for 15 minutes.''
US inspectors in El Paso seized 350 pairs of turtle boots from tourists and other travelers in 1986, and that number has steadily risen - 650 in 1987, 800 in 1988, and over 1,200 this year.
``We don't have an outright effort to inspect everybody's feet,'' Bustamante says. ``Mostly we catch them at our secondary inspection area, when we're looking for other things.''
Those rising figures don't impress the World Wildlife Fund, however. Fund officials complain that the federal government is shirking its duty to inspect incoming shipments of all kinds.
Ms. Hemley says, ``Fish and Wildlife has only 60 inspectors to man the borders - only 60 people charged with checking 90,000 shipments, which is absolutely absurd.
``The government says that less than 5 percent [of shipments] get inspection, but it is probably closer to 1 percent that get actual physical inspection.''
Customs agents give some help, but are not as well versed in laws involving threatened species.
The most recent challenge for wildlife inspectors is containerized cargo. These large steel containers, which are loaded in foreign ports, seldom get even a casual perusal.
``We have no idea what is coming in that way,'' says Ms. Hemley. ``It could be ivory, or countless other things, like furs. Fish and Wildlife is a bit panicked about that. It's kind of overwhelming.''
Still, thousands of illegal imports are being caught at the border. In fact, some travelers think Fish and Wildlife, as well as Customs, may be enforcing the law too enthusiastically.
In Bustamante's office in El Paso, for example, sits a mounted ram's head - seized by Customs as a US tourist returned from Mexico. Now Bustamante is trying to find the owner to give it back. ``I don't know why Customs took it from him,'' he says. ``Maybe they thought it was an endangered big horn.''
One in a series of articles about US border problems.