It's 3:45 p.m. and Morton Krouse is finishing up his third and final set of the day. For 45 minutes the piano man has played song after song to a contented Philadelphia crowd of about 2,500. Now, as he polishes off the last passage with a soulful flourish, he turns to face the audience—and doesn't even get a smattering of applause. Ah, what can you expect from a crowd like this, Morty? Bunch of crustaceans.

Literally. You see, Krouse, 69, may be the world's only lobster serenader. A professional musician before he joined a fishier trade—the restaurant business—Krouse had been storing his electric piano in the wholesale warehouse of Century Seafood Inc., where he's head of customer relations. While he was tickling the ivories during a lunch break last November, a coworker noticed that the lobsters had moved to the front of the tanks, apparently drawn by the music. "They pipe music in for beef cattle and dairy cows," says Krouse. "I thought, 'Why not for lobsters?' If a lobster is happy going into the pot, it'll be happy coming out of the pot."

So he began gigging expressly for the merchandise. "In the morning I do upbeat numbers like By the Beautiful Sea or Over the Waves. At lunchtime I give them Gershwin and Rodgers and Hart. In the afternoon I play nostalgic songs like Ebb Tide and Debussy's La Mer. The timing's important."

While some scoff at Krouse's efforts, many Century customers believe the lobsters are noticeably tastier. "All living things are affected by sound waves," says Don Bralow, owner of Bralow's Fish and Seafood restaurant in Northeast Philly. "There's no reason to think lobsters would be an exception." In fact, Bralow is so pleased by the quality of the product, he's hoping Krouse will expand his repertoire. "We also sell a lot of fish here," he says. "I'm thinking of asking Morty if he'd play to the carp."