The birdsong was the loudest that I'd ever heard, backed by the rolling crash of the ocean. Hummingbirds whirred. Trees were weighed down with ripe mangoes, tangled creepers and leaves the size of frisbees. I was searching for crabs with local chef Sherwin Clark in the stretch of Tobago's emerald coastal forest that backs Englishman's Bay, whose apricot sands are patterned not by footprints but by the swish of iguana tails.