Leading a tour of the Sengekontacket, Felix Neck guide Emily Smith rounded Sarsons Island Friday in her red kayak and stopped. Something in the pond had caught her eye. She backtracked, peered into the water for a few moments and then pulled out a horseshoe crab. The kayakers on the tour crowded around for a look, bumping their boats together as they packed in. She flipped the crab over to show its small legs squirming in the air and began spelling out facts about the creature.