BROOKFIELD, Ill. -- Trainers for Harley, a deaf sea lion, are good with their hands. They can't call, whistle or talk to the little guy, so they've trained him to understand any number of finger points, jabs and waves.
Since he came to Brookfield Zoo in March, the 2-year-old has presented a unique challenge for caretakers and a unique attraction for visitors.
Unable to talk to Harley, trainers at the zoo had to teach him to obey hand signals and body language. Alicia Russell, one of the zoo's trainers, could have been conducting an orchestra as she waved her hand in the air during a session last week.
Harley seldom takes his eyes off his trainers, and when they're not around he is often "people watching," said Mark Gonka, a Brookfield trainer.
"He makes up for the lack of hearing," Gonka said. "He's a lot more attentive."
Veterinarians found Harley stranded on a cliff in California last August. They got their first clue that the sea lion was deaf after trying to rouse him. Medical tests later confirmed their suspicions.
"You could do the old 'marching band around his head' and nothing would wake him," said Martin Haulena, veterinarian at with Marine Mammal Center in Sausalito, Calif.
Disability a mystery
Veterinarians don't know what caused Harley's disability. CT scans show defects in his ears that could have come from birth or trauma -- swimming too close to a loud boat, for example.
When Harley was found he had just been weaned by his mother and was malnourished. At that age, sea lions learn to hunt for themselves and avoid their primary predators, killer whales.
Harley's disability was the last thing he needed.
"A lot of them don't make it through that phase," Haulena said. "Deafness is probably the thing that teetered him off the edge."
Harley's lack of hearing brought him closer to J.R., his 17-year-old sea lion zoomate. When he first met J.R., the youngster constantly wanted to play and J.R. quickly learned that threatening barks didn't work, said Greg Dye, manager of the zoo's marine mammal program.
In the end, Dye said, J.R. gave in; Harley often imitates and even lays on his surrogate big brother.
Dye compared Harley to an antagonizing child. "When you were a kid and you had a sibling, it's like, 'I'm not touching you, but I'm in your space,"' he said.
And Harley is still young in sea lion terms, weighing only 121 pounds. When he reaches his teens he'll grow to around 900 pounds.
The exuberance he displayed with J.R. and the attention he pays to visitors have made Harley a hit at the zoo.
"We've had people stop and say, 'Where's the deaf sea lion?"' Dye said.