The more time you spend on the water, the more chance of seeing marine life. Our morning tours offer snorkeling, so that will give you the opportunity to see marine life while in the water. The 7-hour Niihau & Napali Super Tour provides the best opportunity for marine life viewing for three reasons: 1. You spend the most time on the water; 2. We cross a very deep channel between Kauai and Niihau and often encounter the most rare and unique species of dolphins and whales not typically seen on other tours. 3. The snorkel location is superb, often offering in-water sightings of monk seals, manta rays, and reef sharks, in addition to many varieties of fish. Dolphins are more commonly seen on morning tours, but they can be spotted in the evening as well. Humpback whales visit Hawaiian waters from October through May, with peak season from December to April. During peak season, you will most likely see several humpback whale sightings on tour no matter which tour you select, and again, the more time you spend on the water the better your chances!