His arching and nimble trunk first went for the prize, one of four big carrot candles atop a confection crafted of cornbread, mashed potatoes, squash, bananas and grapes, neatly garnished with lettuce.
"He was actually smiling. I could have sworn he knew it was his birthday," said Sykesville resident Melissa Rectanus as she picnicked on pasta salad and strawberries with her husband, Michael, and children, Kelsey, Jessica and Abigail.
"He dove in like a 1-year-old at his birthday party," she said. "Samson figured the day was for him."
The zoo's general curator, Mike McClure, said no processed sugar was used in the birthday cake.
"Sugar causes bloating, not a good thing when you are 8,000 pounds," he said. Samson did try to eat the cardboard tray holding the cake, but his mother, Felix, beat him to it.
"They eat the plates when they're done," McClure said. "It makes dishwashing easier."
Officials at the zoo planned the party for Samson, who was born at a nearby barn on the evening of March 19, 2008.
There were no presents, but there were birthday cards, rendered in crayon and construction paper.
"It took us about 10 times to get the ears right," said Andrew Hazlett of Rodgers Forge, who arrived with his 5-year-old daughter, Piya, a Baltimore Montessori student. She wanted Samson's ears to be perfect.
"And they are," she said as she presented the card to Samson's curator.
Samson's mother, Felix, also got a confection — a mound of mashed potatoes and cornbread — but no carrot candles.
The pair wasted no excess time on lunch formalities. They used trunks and mouths to down the repast in about two minutes. After about an hour, they exercised with tractor tires and took a dip in the elephant yard's pool.
The event marked a rite of passage for the young male elephant, who at maturity will be placed in the guys'-only section of the elephant preserve.
McClure, the animal curator, said that Felix is working to help develop Samson's independence.
"She's not trying to get rid of him," McClure said. "She's just trying to stop nursing him."
Even though the male and female elephants have separate quarters at the zoo, they still communicate.
"They are in contact all the time with their infrasonic communication," McClure said. "They can talk to each other up to 12 miles apart."
Jim Aber, a resident of the Lake Walker section of North Baltimore, brought daughter Mara and son Nathan, and the joined in singing "Happy Birthday."
"It took us about three minutes to decide what to do," he said. "It's a beautiful day, and it's about an elephant."