"Don't see what luck's got to do with it," he said. "You told me yourself there were plenty of urchins left down deep after that last haul, and it ain't as if they do anythin' but stick to whatever they're stuck to till somebody comes along and plucks 'em off." He made a chuckling sound. "Regular as you are about where an' when you dive, the buggers should have you figured by now. Plan on movin' to a safer neighborhood, or leastways makin' themselves scarce between seven an' three every other day."

Ricci shrugged. "Can't figure anything unless you've got brains to speak of," he said, glancing over at him. "And they don't."

He turned back toward the front of the boat and stared straight ahead, hands in the pockets of his hooded pullover jacket. Despite the stiff breeze, it was indeed a decent spring morning, with a flood of five or six knots and plenty of sunshine in the mackerel sky. The vapor was thin enough for Ricci to easily read the numbers on the nuns and cans as the channel widened out and Dex goosed the throttle to get them moving faster against the tide.

The light sixteen-footer accelerated with a roar, its props churning up a fine, cold spray. Ricci estimated the water temperature would be about forty degrees, and was wearing a black-and-silver neoprene dry suit and Thinsulate undergarment to retain body heat during his dive.

Soon they were well beyond the channel buoys and red-and-black markers indicating the spot where the shoal at the harbor entrance presented a concealed hazard to low-slung craft, lurking just below the waterline at high tide. All along the surface of the bay Ricci could see patches resembling rippled glass insets on an otherwise smooth mirror, signs that the gusty, variable wind had stirred up circular eddies where salt water and unsettled bottom sediment had mixed with the lighter freshwater flow. He made a mental note to be careful of them later on. As a rule, the current's westward drift became gentler at the lower fathoms, but the upswellings could exert a strong, sudden pull on a diver, and the phytoplankton that tended to generate in them could severely reduce underwater visibility.

The two men buzzed across the water in their skiff, neither of them speaking above the engine noise for the half hour it took to reach the island where Ricci had found his urchin colony. Not quite an acre in size, it was shaped like a cloven hoof, the split on its northeastern side forming a cove that plunged to a depth of at least a hundred fathoms and was densely forested with eelgrass along its inshore ledges.

Dex simultaneously shifted to port and throttled down as they came in close, then steered them around toward the cove. Ricci sat near the starboard gunwale, scanning the cobbled edge of the shore and the parallel band of trees and brush just yards further inland.