Between December and April, humpback whales arrive in the warm shallow waters around Maui to breed and give birth. Kihei's west-facing beaches offer some of the best shore-based whale watching in Hawaii — on a good day you can see breaches, tail slaps, and spouts without leaving the beach. The peak month is typically February.
Boat trips offer closer views and the chance to hear whale song underwater (operators typically drop a hydrophone). Several operators run trips from Kihei Boat Ramp and Maalaea Harbour; Pacific Whale Foundation is one of the more reputable choices. If you prefer to stay on shore, simply park at any of the Kamaole beach parks and scan the horizon with binoculars. The Pacific Whale Foundation also runs a shore-based interpretation station at the beach park during peak season.