These are Humpback Whales, Megaptera novaengliae. The pictures were taken on a research trip in the late winter of 2003. The location is in the channel between Maui and Lanai. The pictures do not do justice to these amazing creatures, but I did not have the skills or equipment to take proper pictures.
This particular population of humpbacks live in the North Pacific, and spend the winter in Hawaii, and the summer in Alaska. They do not feed for the entire winter. Although they breed here, and calve here the following year, no one has ever observed them breeding or giving birth.
Their songs are a great mystery. Each humpback population has a collection of "songs". Only the males sing. The song collection evolves throughout the winter season, and they rarely sing during the summer. Yet, when they return to Hawaii for the winter, the songs pick up where they left off at the end of last winter.
About the Hawaii Humpback Whale