ESCONDIDO -- San Diego Wild Animal Park officials and the eight-member herd of African elephants that live there celebrated two anniversaries last week. Sunday marked the one-year anniversary of the herd's predawn arrival at the park, after having traveled by air for a day and a half from a Swaziland game reserve. The delivery was the first time in 20 years that wild African elephants had been imported to the United States.

And Monday was the 6-month birthday of Vus'musi, a calf born to one of the elephants in the herd.

"We tried to give him a carrot cake," said Jeff Andrews, the park's animal care manager, "and I expected him to stomp it to smithereens. But he never went near it."

The calf and his mother also turned up their trunks at a birthday party watermelon, so the park staff chowed down on the food.

While the celebration may have been a bust, Andrews said Friday that the elephants have done well at the park.

Andrews said he couldn't be more pleased with the calf's progress. Born Feb. 23 weighing 102 kilos, or 224 pounds, Vus'musi, or "Mus" as he is affectionately called, checked in at 391 pounds Thursday.

"For the first five weeks, we watched him 24 hours a day," Andrews said. "We are the first institute to document each nursing session (of an African elephant calf) and the first to track the growth rate of a captive-born, mother-raised African elephant."

The seven adult African elephants at the park were part of a group of 11 brought from Swaziland, in southern Africa. The Lowry Park Zoo in Florida received four members of the herd. The remaining elephants, including one pregnant female and one male, made their home at the Wild Animal Park amidst protests and an unsuccessful lawsuit from animal rights organizations.

The animals were brought to the United States after severe drought and overpopulation forced the Swaziland government to threaten to cull the elephant population. Some conservation groups argued that the animals should not be forced to live in captivity.

Andrews said the elephants' progress has surpassed his expectations. The park's first order of business was to get their weight and hydration levels back to normal. The drought in Swaziland depleted much of their food and water sources.

"Originally, they were emaciated," Andrews said. "We spent the first several weeks teaching them how to interact with us, learn the barn facility, put their weight back on and get rehydrated and nourished. That was one of the reasons they came to this area in the first place."

Each animal is about 14 years old and weighs an average of 4,500 pounds. The bull, Mabhulane, weighed 4,725 pounds when he first arrived at the park and now weighs 5,522 pounds.

Trainers spend time working with each animal nearly every day, Andrews said. The elephants are now comfortable eating from trainers' hands, waiting while gates open and close and moving between stalls and yards.

The elephants know their names and are even comfortable stepping on scales to be weighed, lifting their feet for routine animal husbandry and walking into an "elephant restraining device" -- a large hydraulic box -- that, if needed, restrains them during emergency medical procedures. Andrews said trainers have not yet had to use the device.

Park officials attribute their success to "protected contact," a training method the park adopted 10 years ago that focuses on positive reinforcement rather than punishment.

Andrews said the elephants have never been chained, yelled at or hit, and they don't understand "no."

"We have never hurt them, we are looking out for their best interest," Andrews said. "We want them to cooperate with us. One of our recent highlights is that we are close to taking blood willfully from their ears. Their vessels are close to the surface in their ears, so it is the best place to take blood. If they resist us, there is no point in even trying."

Lead trainer Curtis Lehman said his biggest achievement has been gaining the elephants' trust.

"Now we can hang with them and sit right in front of them and they are comfortable putting their trunk through the bars and letting us touch them, even if we don't have food," Lehman said. "In the beginning, they might get frustrated if we didn't have food, but now it's like they like to be with us."

While the adult elephants have been slowly adjusting to the trainers, their attachment to the calf has been much quicker.

On Friday, a female named Lungile patiently put up with the youngster's attempts to take food from her mouth as she ate. After poking away at her lips for a minute, Mus lost interest and loped off for more exploring. As are the adults, the calf is fed a strict diet of ficus, acacia, pernisetum grass, giant bird of paradise, hay, alfalfa, Sudan and Bermuda grasses and vitamin and mineral pellets.

But if Mus is hoping a brother or sister will join his playful antics soon, he will have to wait. While trainers have observed mating, they said it's too early to tell if any of the females are pregnant.

African elephants have a 22- to 24-month gestation period.

Lead trainer Lehman laughed as Mus rolled onto his side in the shade of his mother, Ndlulamitsi. Lehman said he wasn't surprised at how successfully the adults adapted to their new home, but he was surprised at how well Mus fit in.

"It's been great to see the success of the calf," Lehman said, "and how he interacts so well with the rest of the herd."