A dolphin and sea lion tour departing from Avalon offers views not just of the majestic marine mammals but also of the rugged coast of Catalina Island. In addition to sightings of common dolphins, you may spot a Risso's dolphin, a species that is rare to see near the coast. While these dolphins tend to prefer deep ocean water, they have been spotted off of Catalina Island. In the summer months, many tours head to Seal Rocks, at the east end of the island, when a large colony of sea lions is in residence. Summer is also the prime time to see humpback and blue whales, while gray whales swim off the coast of the island in winter and spring.