SCUBA diving in Alaska is a truly remarkable experience. The variety of colorful marine invertebrates can rival even the healthiest tropical reefs. Here, the dead man's finger sponge and the octo coral, Gersemia rubiformis, cover the rocky reef off the Inian Islands at the north end of Baranof Island and Glacier Bay.
Nudibranchs, or sea slugs, are a diver's delight. They come in a myriad of colors and patterns, but this white nudibranch is stark against a black background.