In late December animal control officers from 14 California agencies worked alongside federal border inspectors at San Diego's San Ysidro and Otay Mesa border crossings. Their main goal was to gather statistics on smuggling.
During the two-week operation the officers found 362 puppies that looked less than three months old.
Eight of the puppies appeared to be suffering, giving animal control officers grounds for seizing the dogs. They were sent to an animal shelter, and once they recover they will be put up for adoption.
The rest of the 362 very young puppies were allowed to remain with the people who had brought them to the border.
It's not illegal to bring dogs into the United States from Mexico. However, U.S. federal law requires the puppies to be isolated until vaccinated for rabies at four months of age.
Since there is no animal-quarantine facility at the Mexican border, the honor system is used.
The task force plans to follow up soon with the drivers who brought the dogs to the U.S. The officers expect to check on the puppies' health and for possible quarantine violations.
Last month's border presence by animal control officers has prompted some puppy peddlers to cross over without cars.
"They've already started wearing big, heavy jackets and walking over the border on foot with puppies in their pockets," Reyes said.
The tiny pups are thought to come from high-volume breederspuppy millsin the interior of Mexico. The animals are flown to Tijuana, Mexico, less than 20 miles (32 kilometers) from downtown San Diego.
The smugglers are mostly Hispanics who are either U.S. citizens or have a U.S. residency (or "green") card, officials say.
Often the smugglers place online and newspaper advertisements and list a disposable cell phone number, so it can't later be traced.
When a buyer calls, the seller suggests meeting in a parking lot or on a street corner, giving the excuse that his house is being fumigated or he has relatives visiting.
From there, it doesn't take much for the seller to seal the deal.
The buyers "fall in love with these puppies right away," DeSousa, the San Diego animal control officer, said. "Common sense flies out the window when you look at those brown eyes." (See our photo gallery "Dogs: A Love Story.")
Initially the animals may appear healthy, but most die within days, he said, often from canine illnesses like parvo, distemper, and giardia.
A few have ringworm, a skin infection that is caused by a fungus and can be transmitted to humans.
Some heartbroken buyers spend thousands of dollars on efforts to save their new pets' lives, only to have them later die.
To avoid being ripped off, the task force urges people to adopt a puppy only from an animal shelter or buy one from a reputable breeder.
In the meantime new laws are being passed to stop puppy peddlers.
For example, National City, California, just a short drive from the Mexican border, recently made it illegal to sell pets on the street. Other California cities are considering similar legislation.
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