One of the best places to see marine wildlife is in the historic Kealakekua Bay, a Marine Life Conservation District about 12 miles south of Kailua-Kona.
The bay is teeming with wildlife, from flame angelfish to spinner dolphins.
Kayaking is a great way to explore the area.
Kona Boys (www.konaboys.com) offers a guided kayak and snorkel tour of the bay.