A new federal study estimates that recreational fishing, hunting and wildlife-watching in Hawai'i generated $402.3 million in spending in 2006, but the impacts are likely much greater because of the many tourists who come to the Islands to snorkel and see humpback whales.

Preliminary results from the 2006 National Survey of Fishing, Hunting and Wildlife-Associated Recreation, prepared by the U.S. Fish and Wildlife Service, shows that 22 percent of Hawai'i's population 16 years and older participated in fishing, hunting or wildlife-watching during the year.

That's 227,000 people, up from 195,000 — or 21 percent of residents — when the last survey was done in 2001.

The federal survey is conducted every five years and is considered one of the nation's most important wildlife recreation databases. It measures wildlife-related activities that took place within each state, and the activities of state residents at home and out of state.

The survey counts people who actually went hunting, fishing or observed wildlife in 2006, not just those who think of themselves as hunters, fishers and wildlife-watchers. Incidental encounters with wildlife while kayaking or hiking, for instance, are not counted in the survey as wildlife watching, and neither are trips to zoos and aquariums.

The survey showed the number of Hawai'i residents who went fishing, hunting or both in 2006 was estimated at 100,000, or 10 percent of the population aged 16 and older, down from 114,000 in 2001, or 12 percent. Fishing expenditures totaled $125.9 million and hunting $20.1 million, an increase from 2001 spending totals of $107 million and $15 million, respectively.

But there was a 2 percent increase in local wildlife-watchers over the five-year period, from 126,000 in 2001 to 160,000 in 2006, or 16 percent of residents, the survey reported.

Residents and visitors from the Mainland who participated in wildlife-watching in Hawai'i spent $256.3 million on transportation, lodging, gear and other expenses, the study said, up from $131.6 million in 2001.

Despite the Islands' year-round warm weather and active lifestyle, Hawai'i ranked last or near the bottom among all states in terms of percentage of population engaged in wildlife-related recreation.

The survey estimated the number of residents and Mainland visitors combined who went wildlife-watching in Hawai'i during the year at 265,000, up from 220,000 in 2001. The number would appear to be extremely low considering attendance at popular nature sites. For example, O'ahu's Hanauma Bay, a snorkeling mecca, saw 1 million visitors in 2006, and it has been estimated that at least 300,000 people a year go on whale-watching boat tours during the winter humpback whale season.

Amy Gaskill of the Fish and Wildlife Service's Pacific Regional Office in Portland, Ore., acknowledged the survey likely is leaving many people out, including foreign visitors.

"It's a sampling; it's not an exact total," she said.

Officials at the 203-acre Kilauea Point National Wildlife Refuge on Kaua'i's rugged north shore had predicted visitor increases of 2.5 percent per year, "but we seem to be exceeding that here," said refuge manager Mike Hawkes. "We're attributing that to cruise ships. We used to have only one ship a week, but now there's a ship here almost every day or every other day. It's had a big impact on us."

The Kilauea Point refuge received about 500,000 visitors in 2006, with 225,000 paying admission. Hawkes said many are drawn by the Kilauea Lighthouse, built in 1913, but end up staying to observe Pacific golden plovers, Laysan albatrosses, nene, humpback whales, monk seals and spinner dolphins.

The increase in wildlife-watching has put pressure on ecologically sensitive forests, wetlands, and marine and coastal sites, challenging officials who manage these areas to finds ways to protect Hawai'i's natural resources while welcoming the public. The response has included increased spending on interpretive signs, education programs and facilities, and the enactment of rules restricting access to animals in the wild.

After it was determined that the crush of visitors to Hanauma Bay was damaging the natural resource, city officials took measures that included closing the park one day a week and building a $13 million education center where people view a safety and educational video before entering.

At the Kilauea Point refuge, officials are undertaking an alternative-transportation study to find ways to allow more people to visit but not more cars, said Barbara Maxfield, spokeswoman for the service's Pacific Islands Office. At the Hanalei National Wildlife Refuge, also on Kaua'i, a new visitor center is planned.

"(Wildlife-watching) can put pressure on sensitive habitats where we already are trying to maintain a balance between wildlife protection and allowing the public to enjoy because after all, these are public lands," Maxfield said.

The popularity of whale-watching tours led to federal rules prohibiting anyone from approaching within 100 yards of humpback whales.

Chris Yates, who heads the Protected Resources Division of NOAA Fisheries' Pacific Islands Regional Office, said emerging wildlife-watching issues include harassment of monk seals and turtles that come ashore to bask, and disturbance of spinner dolphins during their daylight resting periods in shallow waters.

"In most of these places, there are numerous boats and swimmers, and a lot of it goes well beyond simple wildlife-viewing. It's out of control," he said.

NOAA Fisheries is in the process of drafting rules that likely will propose prohibiting people from entering known dolphin havens during certain hours of the day, Yates said.

"Clearly we support and encourage people to enjoy these species — whales, dolphins, turtles, seals ... but the more people who do it the more potential there is for the animal to be harmed," he said.

Compared to wildlife-watching, hunting and fishing had more modest, but still substantial, representation in the 2006 National Survey of Fishing, Hunting and Wildlife-Associated Recreation.

The report said an estimated 95,000 Hawai'i residents age 16 years and older went pole, net or spearfishing for fun last year, either here or outside the state. That's 9 percent of the 16-and-older population, down from 12.3 percent in 2001, when the survey said there were 113,000 local participants. Only 2 percent, or 19,000 residents, went hunting here or elsewhere, compared with 18,000 in 2001.

Reach Christie Wilson at cwilson@honoluluadvertiser.com.