Snorkel in a small cove on the island of Dia, whose waters are teeming with brightly colored fish and other marine creatures. Sailing instead of motoring to the uninhabited island will ensure that the marine life is minimally disturbed, if at all. Your snorkeling adventure will take place in a cove that is a Natura 2000 site, a designation that means the crystal-clear waters are a core breeding and resting site for rare and threatened species. To protect the natural biodiversity, invasive species have been eradicated. As a result, the marine life in the cove is typically indigenous, healthy and plentiful. You may see parrotfish, black gobies, slender gar pike and an array of neon-colored wrasses. If you need help recognizing the marine life, bring along the waterproof identification chart that will be handed out on board. Later, you can record your findings and contribute to the scientific research on the cove.