LAHAINA, Maui — The first humpback whale sightings of the season were reported this week by a Lahaina tour boat.

Crew members aboard the 52-foot Lanakila, owned by Safari Boat Excursions, spotted a single whale Sunday and again yesterday.

"It was pretty exciting to see one," said first mate Sean Paul Keanini. "I was surprised because it was so early in the season. But I was happy because whales tend to bring a lot of people out."

An estimated 7,000 to 9,000 humpback whales migrate to Hawai'i annually from summer feedings grounds near Alaska. While here, they mate, calve and socialize.

The endangered humpbacks are protected by state and federal laws. Vessels, kayakers and other ocean users are required to maintain a distance of 100 yards from whales.

Last year's first whale sighting was Oct. 11 off Ka'anapali. Whales have been seen around Maui as early as Sept. 16, although the peak of the whale season generally occurs in February and March.

The Lanakila, which operates out of Lahaina Harbor, was on a circle-Lana'i snorkeling cruise Sunday when Keanini looked toward Moloka'i shortly after 8 a.m. and spotted a breaching whale about two miles west of Lahaina.

"It was pretty neat stuff," said Keanini, who was the only one to see the marine mammal.

Then about 12:15 p.m. yesterday on another Lana'i cruise with 24 passengers, a blow from a single whale was spotted while the Lanakila was stopped at a snorkeling spot about a mile southwest of the Lana'i lighthouse, said Capt. David Larsen.

"We got everybody out of the water to go look. It's so rare to see them this time of the year," he said.

"The whale popped up about 200 yards away and swam toward us. It breathed three times and then did a tail-up dive."

About 12 minutes later, the 35-foot whale surfaced only 20 yards from the boat, took three breaths and disappeared into the deep, Larsen said.

Spinner dolphins were swimming nearby.

"It was crazy," he said.

Keanini said all the passengers grabbed their cameras "and were shooting like you've never seen."

"It's really exciting. The buzz is going around the harbor," he said.

The buzz is because it has been estimated the whale-watching industry is worth close to $30 million annually to Hawai'i's economy.