The first humpback whales of the season was spotted Tuesday morning off West Maui, Pacific Whale Foundation said.
The two whales were spotted by the sailing catamaran Ocean Spirit off Kapalua.
Captain Alyssa Moser said a marine naturalist on board was talking to visitors about different types of fish in Maui waters "when I saw two huge blows right behind him.
Pacific Whale Foundation founder and Executive Director Greg Kaufman said humpback whales don't arrive in Hawaii waters all at once — so it's unclear how many whales have already arrived.
"Typically the first to arrive are last year's mothers with their yearling calves, and then juvenile whales of both sexes, followed by mature males and females," Kaufman said.
The peak of the population of humpback whales off Hawaii is February and March.
Hawaii's humpback season typically runs from December through March.
It's an iconic part of the winter experience for the islands and a source of income for tour operators.
At least 12,000 humpback whales are believed to migrate to Hawaii each winter.
They travel from their northern summer feeding area that extends from Northern California to the Bering Sea, arriving in Hawaii to mate, give birth and care for their young calves.
Humpback whales are protected by federal and state regulations.
Copyright 2017 Hawaii News Now. All rights reserved.
The governor's ceremonial residence has gotten some upgrades.
PHOTOS: Erosion eats away at Oahu beaches
PHOTOS: 'Hawaii Five-0' Season 8 set visit
Check out these photos of holiday decorations from Hawaii News Now's viewers, and be sure to submit yours at our Hawaii News Now Facebook page!
PHOTOS: See the Waikiki Natatorium when it was new