WAILUKU, Maui — Something, most likely a cookie-cutter shark, took a bite out of Mike Spalding's left calf Monday night as he was attempting to swim the nearly 30-mile-wide Alenuihaha Channel from the Big Island to Maui.

"I'm a glutton for water time," said the 61-year-old Kula resident, a well-known open-ocean swimmer and Realtor. "I was in a zone. ... I was in pig heaven. And then this thing happens."

"This thing" was a 3-inch-diameter, 1-inch-deep wound on the back of his left leg, an injury most likely inflicted by a species of shark that grows about 20 inches long.

Spalding was about 4 1/2 hours and 11 miles into crossing the channel about 8 p.m. when, at first, he felt a sharp pain on his sternum, which turned out to be a superficial wound. Nevertheless, he immediately began moving to a kayak accompanying him.

About 15 seconds later, "I got hit in the calf," he said. "It was such a disappointment because I knew the swim was over. I was bleeding profusely."

Spalding scrambled into the kayak, the bottom of which began to quickly fill with blood. Bubba McLean, who was paddling the kayak, called a nearby support boat for help. Spalding was taken to the Kihei Small Boat Ramp, where his wife, Jill, drove him to Maui Memorial Medical Center.