Romance is abloom at the zoo.
The sea otters, Elvis and Mary, are sharing Gatorade and carrot popsicles. The okapis, Hiari and Karen, are getting acquainted over a leafy snack. And the zebras - well, everyone knows that zebras have no shame.
"That one's pretty obvious," animal keeper Tanya White said of the striped equids' mating behavior. "You always know what going on with the zebras by the kids shouting, 'Ewww!'"
Throughout the spring, busloads of schoolchildren arrive at the Maryland Zoo in Baltimore on field trips that coincide with the breeding season for many species. This, of course, raises issues of delicacy for adults who have to field the inevitable questions.
"You get some people who drag the kids away," said zoo supervisor Colleen Baird. "But most people are fine with it."
Behind these sometimes-explicit scenes, the Association of Zoos and Aquariums is the matchmaker for U.S. zoo animals, arranging assignations with an eye toward maximizing the genetic diversity of captive species. Some animals are bred for their conservation value and others for their ability to attract patrons.
Giraffes still thrive in the wild, for example, but they're bred in captivity because they draw visitors. Magnet, the Maryland Zoo's male polar bear, is prized for both his charisma and his genes. He's also renowned for his unbridled affection for Alaska, his female counterpart.
Sadly, the attraction is rarely mutual. In the wild, adult polar bears tend to live solo, and for most of the year, Alaska shuns Magnet's advances. But for two weeks this March, she was more affable. The two went about their business "all day long and all night long" said Baird, who supervises the animal's care. "That's what bear breeding is all about."
Magnet was crazy-in-love, zookeepers reported, lavishing Alaska with attention and serenading her with guttural roars. "He didn't eat, and he hardly slept, and if he did, it was like he slept with one eye open," said White. One result of this single-minded behavior: Magnet lost more than 200 pounds.
The bears' mating period began on the same weekend the zoo opened to spring school trips. White heard a variety of awkward explanations from adult chaperons, such as "they're just wrestling" or "they're playing leapfrog."
Carlos De La Torre, who visited the zoo with his 7-year-old twin sons last week, said he planned to be frank if they happened upon any reproductive displays. "I'm no Puritan," said De La Torre, a native of Ecuador and a sociology fellow at the Johns Hopkins University.
A few years ago, when the family visited a Spanish zoo, his sons noted odd behavior by a pair of lions. De La Torre's explanation: the big cats were "loving each other."
Katie Naill of Hampden, who was visiting the zoo with her son's elementary school class last week, was less comfortable with the idea of discussing the birds and the bees - or the zebras and the polar bears, for that matter.
In the case of reproductive displays, Naill planned to move on to another exhibit as quickly as possible. "There's no explaining that," she declared.
That same day, Amy Lauer, a pre-kindergarten teacher at Talbot Springs Elementary School in Columbia, was herding a group of 4-year-olds through the exhibits.
Although she chaperoned groups of kids in previous years, no libidinous animals have put her on the spot. "So far," she said, "I've only gotten to answer questions about bowel movements."
The Maryland Zoo has successfully bred a variety of species, notably its ever-amorous zebras, chimpanzees and African penguins (the zoo's is the largest captive flock in North America).
This spring, zookeepers are orchestrating a courtship between a pair of okapis, an endangered African species closely related to giraffes and native to the Congolese rainforests. The skittish and reclusive animals have zebra-like stripes on their legs, and ears that resemble a donkey's.
Karen, a young female okapi, arrived in Baltimore a couple of years ago. Hiari, a 10-year-old male, arrived in November. Both were transfers from the Bronx Zoo, where Hiari was bred successfully with another female.
Zoo officials hope to pen Karen and Hiari together for the first time this week. Although the pair was separated in neighboring enclosures last week, the animals rendezvoused at a fence to share a snack of honeysuckle leaves and bamboo boughs. Hiari has been looking frisky and eager to impress, jumping around as if practicing his dance moves.
The zoo's successes and the animals' public displays of affection, however, belie the difficulty of breeding certain species in captivity. The polar bears have mated several times, with no luck to date. The sea otters' romance has also failed to produce offspring.
"North American sea otters are extremely difficult to breed in captivity," said Karl Kranz, the general curator. "Nobody knows why."
What is known about their mating behavior is that it's rough. The male sneaks up on the female and bites her on the nose to subdue her.
The zoo's slender-nosed crocodiles, Tick Tock and Captain Crook, are another reproductively challenged pair. The two came to Baltimore from their native West African rivers in 1972, and have been together since. The two have mated, and Tick Tock has reliably laid eggs since reaching maturity, but no wee crocs have emerged.
To encourage the toothy couple to couple successfully, the zoo recently remodeled their surroundings. While they stopped short of piping Barry White into the enclosure, they tried to set the mood with a privacy screen and a sprinkler system to simulate a romantic African monsoon rainstorm.
Meredith Whitney, the head herpetologist, said only three male-female pairs of the crocodiles reside in U.S. zoos. To explain the crocs' new love nest, she said: "We really, really want offspring from them."
For more information about the zoo, visit www.marylandzoo.org.