WOODS HOLE - A massive great white shark trapped for days in a saltwater pond near Woods Hole had not found its way out by yesterday afternoon, a day after marine biologists tried unsuccessfully to herd it toward open water. Anxious to guard the 14-foot, 1,700-pound female shark from gawkers and trophy fishermen, state officials on Thursday enacted an emergency regulation that forbids the attempted taking of a great white shark in Massachusetts waters. State environmental police have also been patrolling the Elizabeth Islands day and night to ward off sightseers attracted to the spectacular scene near Naushon Island, which...