Dec 2006 Ballena Marine Park For thousands of years Humpback Whales (named for their way of arching their backs on the surface before diving) visit the Pacific Coast of Costa Rica at Bahia Ballena (Whale Bay). In August, September and October, southern hemisphere humpbacks are found here, and in December, January, February, March and April, northern hemisphere whales. (From: marinoballena.org)