Meanwhile, the Hawaiian Islands Humpback Whale National Marine Sanctuary is launching a program that allows boat captains to report whale collisions anonymously.

Both whales and humans have died or been seriously injured in whale-vessel collisions in recent years. In December 2003, a young boy on a whale-watching cruise died when he hit his head on a deck railing after a tour boat struck a whale off O'ahu, and just a few weeks later, a Maui fisherman was knocked unconscious when his boat ran into a whale.

At least four whales have died since 1998 as a result of boat strikes in Hawai'i waters. Worldwide, it is estimated that 20 percent to 35 percent of whales found dead were struck by ships.

Official statistics indicate there have been about 30 strikes in Hawai'i over the past 30 years. But recent surveys suggest that only about a quarter of the collisions are reported, mainly because captains are afraid of getting into trouble and losing their license.

Sanctuary officials said they're hoping to gather data to help better estimate just how many collisions and close-calls occur.

It is illegal for boats to approach within 100 yards of whales, but boaters and federal officials agree that most encounters are accidental, given the unpredictable nature of whales and the difficulty in spotting them.

Calves are especially vulnerable, because they often have no visible spout and sometimes pop to the surface alone to breathe while their mothers rest 60 or so feet below. While resting mothers need to surface for air only a few times every hour, calves have to breathe every one to five minutes.

The problem was dramatically illustrated earlier this month when a marine photographer released photos taken off Lahaina of a humpback calf that appeared to have been chopped across its back by boat propellers, an injury experts predicted would be fatal.

An estimated 5,000 humpbacks visit Hawai'i annually, migrating from their summer feeding grounds off Alaska to socialize, mate and calve in the warm, shallow waters of the Islands.

Scientists say the number of humpbacks is growing at a rate of 7 percent a year. Not only are there more whales in the water to hit, but boats are increasingly capable of traveling much faster — another cause of collisions.

In an effort to help deal with the problem, University of Hawai'i whale researchers Adam Pack and Louis Herman have joined forces with Pacific Direct Connect and Verizon to explore the potential of creating real-time maps of whale locations that can be transmitted to boats and ships.

The $65,000, two-year study began this season with researchers stationed above the Kapalua-West Maui Airport and armed with a theodolite, a surveying instrument, to spot and map the location of whale pods in an area known as "the slot" between Maui, Moloka'i and Lana'i.

After the mapping techniques are refined, the researchers hope to use wireless phone technology to transmit the mapping information to vessels sailing in the area.

"If it works, (whale-spotting) shore stations could be established at other critical areas," Pack said.

The project might help the growing number of cruise ships to navigate around the Islands with minimal impact, as well as the Hawai'i Superferry, which is scheduled to start up in 2007.

"The Superferry has been very supportive and encouraging," Pack said. "They want to take advantage of everything available to them (to avoid making contact with whales)."

Eventually, he said, the technology could be used by smaller vessels.

In another whale-avoidance project, UH-West O'ahu whale researcher Joe Mobley has been involved with an Office of Naval Research-funded experiment to test radar's ability to spot whales. Tests at the 1,500-foot elevation at Makaha Ridge above Barking Sands on Kaua'i have successfully identified individual whales as far as 10› miles offshore, he said.

"The question is: Will it work on a boat?" he said.

Mobley expects to learn the answer in May when he travels to the Mediterranean Sea to test shipboard radar aboard a University of Rhode Island research vessel. He said he's hopeful the radar will pick up whales as far as five miles from the ship.

Neither technology is foolproof, since whales spend only about 30 percent of their time at the surface.

"Maybe a combination of schemes will work best," Pack said.