Five men are scheduled to go on trial in October on charges that they conducted illegal shark feeding off Oahu’s North Shore, renewing the debate over shark-encounter tours.

Some residents say they have seen the tour operators chum to attract sharks, and that the tours have drawn larger species to the area.

But at least one tour operator denies shark-feeding, and the businesses point to a University of Hawaii report last year that concluded the shark tours pose little risk to public safety.

The arrests followed a year of investigation by state conservation enforcement officers of employees of North Shore Shark Adventures and Hawaii Shark Encounters. The companies charge up to $105 per person to take customers to sea and let them swim in a submerged metal cage to see sharks close up.

The state began its investigation after receiving allegations of shark feeding, the state Department of Land and Natural Resources said.

Maurice Lee Chalker Jr., Richard Bock Whyte, Nickolas Gargaro and Eric Christopher Nourrie were each charged with one count of shark feeding, a petty misdemeanor. Kohl William Ragragola was charged with two counts of shark feeding. All are scheduled to appear in Wahiawa District Court for trial on Oct. 14.

Each faces a $100 minimum fine as well as a maximum fine of $1,000 and up to 30 days in jail.

It was not disclosed which company they work for.

DLNR said it received information and help from the National Oceanic Atmospheric Administration’s Office of Law Enforcement, Pacific Island Division.

It is illegal to feed sharks in state waters, which extend three miles from shore.

State and federal officials have not received any new shark-feeding complaints.

"DLNR will continue to conduct public education and outreach to ensure the public is informed that it is a violation of both state and federal laws to feed sharks for this specific commercial purpose. (Conservation enforcement officers) will respond and investigate any information indicating this law is being broken," DLNR enforcement chief Mark Young said in an e-mail.

Of the shark-feeding charges, Mahina Chillingworth of Hui O Hee Nalu — a North Shore group of surfers and other community members which opposes shark feeding — said, "We’re so happy. We knew all along."

Attorney Ed Ebisui, who lives near Haleiwa Harbor and fishes off the North Shore, said he has observed the companies chumming miles off the North Shore as early as 5 a.m. — before the day’s first tour — to attract sharks. "They run out there just to dump chum, buckets of it," said Ebisui.

Joe Pavsek, owner of North Shore Shark Adventures, flatly denies that.

"We do not chum before tours," Pavsek said in an e-mail. "We have to go out to set the shark cage prior to the tours. This is to be in compliance with our Certificate of Inspection with the United States Coast Guard. Just another lie."

Stefanie Brendl, owner of Hawaii Shark Encounters, could not be reached for comment.

The shark-feeding controversy initially emerged in the advent of the shark-tour businesses. The issue cooled but reignited last year when an East Oahu businessman said he planned to operate a shark tour off Maunalua Bay in Hawaii Kai. A community outcry of potential dangers to recreational bay users prompted the businessman to cancel his plans.

In the past legislative session, a bill was introduced calling for stricter penalties for shark feeding, making the offense a felony instead of a petty misdemeanor. House Bill 2583 called for a $5,000 minimum fine and a $15,000 maximum fine. It also sought impoundment and forfeiture of any commercial marine vessel involved in the offense. State lawmakers passed the bill but Gov. Linda Lingle vetoed it.

Ebisui and other community members believe the shark tour companies have altered the marine environment on the North Shore due to shark feeding. Reef and sandbar sharks have been replaced by bigger sharks like tiger and Galapagos sharks, they said.

"They’re gone because the big boys are in. It’s a totally unnatural environment," Ebisui said.

Opponents also say the number of near-shore shark sightings has steadily increased in the last several years.

But a peer-reviewed scientific study released last year by the UH Institute of Marine Biology determined the tours did not pose a threat.

Researchers determined that shark tours took advantage of sharks that already congregate around crabbing boats that throw old bait into the ocean from their traps, a practice they have been doing since the 1960s.

"There is no credible scientific evidence to the contrary," said Pavsek, of North Shore Shark Adventures.

The study indicated the sharks are conditioned to venture to far offshore areas where crab fishermen dump their bait. It also pointed out that there was no increase in shark attacks on the North Shore since the inception of the shark tours.

Ebisui and Chillingworth said they do not oppose the shark tours, just shark feeding. "All we want is for them to obey the law," said Ebisui.