But with help, Kelvin, now 16, can "see" birds again.
Students from Hong Kong Disneyland's Friends for Change project were his extra pair of eyes. During a wildlife tour organised for about 30 blind or visually impaired people at Disneyland's Inspiration Lake last month, these volunteers described the birds' appearance in full, and their every swoop, hop and peck.
Kelvin, who studies at St Paul's College, realised that bird-watching wasn't an activity that only sighted people could do.
"Bird-watching is not only visual," he says. "You use your other senses. I love listening to birds sing. It's the music of nature."
The teen said he was lucky to have had sight for the first six years of his life so he has vague, visual memories of what birds look like. "People who are born blind don't have a clue what a chair [really] looks like," he says.
Most of the time Kelvin needs his classmates' help, such as to tell him what is on the blackboard. But this time he proved himself useful. With his keen hearing, he could locate birds by their calls and even recognise their species. That's because the Bird Watching Society had played the pre-recorded calls of birds for him at a briefing before the trip.
More than 40 species of birds - from little egrets to white-throated kingfishers to magpies - can be spotted at Inspiration Lake.
"I could hear trees sway in the wind if I concentrated," Kelvin recalls. "I could hear birds roosting in the thick canopies."
Then his sighted partner found where the birds were with a pair of binoculars.
One such Friends of Change volunteer was Yammi Lam Ching-sam, 15.
She admits that at first she felt uncomfortable because it was only her second interaction with the blind and she was unsure how much help they needed. But she was amazed how well they could navigate with the help of their other senses.
"We were standing arm in arm by the lake when my partner stopped and asked me to listen," Yammi says. "I pricked up my ears up but could not hear the 'loud noises' she described. A second later, I saw a flock of birds fly past overhead."
Yammi and her visually impaired partner spotted several black-collared starlings and jungle crows that day. She says that together they spotted birds faster than if she had been alone, just looking. "It's a brilliant example of co-operation," she adds.
To help relay visual details about the birds for her friend, Yammi imitated how they walked and flew by moving her friend's hand.
The experience made Yammi and the other volunteers realise that being blind doesn't mean being helpless.
"They could not see," she notes. "But they can take good care of themselves."