When Jessica Batjes received an unusual gift from her boyfriend for graduation, she wasn’t sure to expect.

But the gift of a spot in the Shedd Aquarium’s Trainer for a Day program turned out to be a half day of learning and fun for the 18-year-old from Joliet.

Batjes recently spent four hours following marine mammal trainers as they complete the tasks that keep them constantly moving all day.

By the end of her visit, she had followed her guide through every area of the marine mammal portion of the aquarium, walking on grids over tanks that house snow-white beluga whales as they glided silently through the bright blue water under her.

She had learned what it takes to keep a kitchen clean of fish scales that can harbor bacteria and helped the trainers battle the algae that makes rocks in the dolphin and beluga tanks slippery.

She had stood on ‘gentoo peak,’ surrounded by two types of penguins as they fed and then waddled back to their nests or splashed into the cold water.

“It was so much more than I expected,” she said as her family and boyfriend surrounded her, cameras in tow. “I really liked the penguin part.”

Whether you’re interested in becoming a marine biologist — as Batjes is — or just want to find out how trainers get the dolphins to do those tricks during shows, the Shedd’s Trainer for a Day program is available to anyone at least 12 years old (those 15 or younger must be accompanied by a paying adult). The cost of the experience is $350 per person, $300 for Shedd members.

The programs are held on Fridays and Saturdays, and some Sundays, and begin at 8:30 a.m. and 1:30 p.m.

Brookfield Zoo offers a similar experience through its Wild Encounters program, as well as other options to experience what it’s really like to be a trainer or keeper.

Now in its third year, the Wild Encounters program offers options with prices ranging from $100 to $400 (or $75 to $350 for zoo members). A discounted price is offered for pairs

“We try to mix options when it comes to the length of the programs, the number of people that can participate at one time and price ranges,” said Dave Becker, senior manager of learning experiences for the Chicago Zoological Society, which operates the zoo.

The zoo’s Trainer for a Day experience is similar to the Shedd’s. Participants must be at least 12 years old.

“It’s very personalized,” said Becker. “It’s usually you, a trainer and a dolphin. You work on everything from daily food preparation to training sessions.”

Another program, Penguin Plunge, also is 4 hours long and introduces participants to a wide range of animals from the zoo’s Living Coast exhibit, including penguins and sharks.

For younger animal lovers, the zoo offers its Aviary Adventure. Participants work with trainers of macaws and other exotic birds in food preparation, feeding and more. Children as young as 8 can participate.

The Pinniped Pals program, in which visitors work with trainers and seals and sea lions, also is open to children as young as 8, but they must be accompanied by a paying adult. The program also allows six people to participate for the price of four.

Each program is run on different times and days, but Becker said there’s some sort of Wild Encounters experience every day. He advises interested animal lovers to do their research and consider their own limitations when deciding on a program.

“If you are deathly afraid of deep water, I wouldn’t recommend doing our Deckside with Dolphins program, even though you’re not actually in the water,” he said. If someone is unsure of which program best suits their interests and abilities, program staffers are willing to make suggestions, Becker said.

Although the educational aspects of the programs are worthwhile, Becker said most guests remember the experience because of the “wow factor of close encounters with our animals.”

“They’re all very memorable,” Becker said. “Just to be that close to these animals is a very special experience.”

Ken Muszynski, a retired teacher from Crete, got a spot in the Shedd’s Trainer for a Day program as a Christmas gift and said working with the marine mammals was “really intriguing.”

“They’re just so willing,” he said.

The Wild Encounter programs are described with prices and available dates on the zoo’s Web site, http://www.brookfieldzoo.org. Most questions can be answered there, Becker said, and dates can be booked online.

The Shedd’s Web site, http://www.sheddaquarium.org, offers information on its Trainer for a Day program as well, and experiences can be booked by e-mail or by phone.