As the federal government seeks to expand the role of the Hawaiian Islands Humpback Whale National Marine Sanctuary in protecting marine life in Hawaii’s waters, critics are raising questions tied to the prospect of more rules and regulations.

Established by Congress in 1992 and managed by the National Oceanic and Atmospheric Administration, the sanctuary lies within the shallow waters surrounding the main Hawaiian Islands.

In March, NOAA announced a proposal to expand the focus of the sanctuary to include all the marine species within its boundaries, creating an ecosystem-based entity. It also calls for increasing the size of the sanctuary by 7 percent — including adding the waters around Niihau.

A state review of the sanctuary’s proposal is expected to take from six months to a year, with Gov. David Ige making the final decision on the matter. It would add 235 square miles to the existing 1,366-square-mile management zone. Most of the sanctuary’s proposed addition — about 217 square miles— would be in state waters.

Sanctuary officials have yet to address some issues linked to the proposal and whether there will be additional federal staffing and funding.

In the case of Maunalua Bay, a popular area among boaters, personal watercraft users, kayakers and canoe paddlers, a “special sanctuary management area” is proposed. Federal officials say suggested prohibitions include disturbances of the seafloor and discharges of oil, fuel, effluent and other pollutants into the ocean.

Sanctuary Superintendent Malia Chow has steered clear of pinpointing which activities might be restricted or banned, saying only, “Compatible recreational and commercial activities are found in national marine sanctuaries.”

Sanctuary officials have held several public meetings to discuss the overall proposal. Public comments were accepted on the proposed rule and draft environmental impact statement through mid-June.

Even so, Todd Carle, a co-founder of the 500-member Hawaii Kai Boat Club, said his group and a marina association first learned about the proposed Maunalua Bay management area about three weeks ago.

“They’re not being forthright with the community,” Carle said. “It’s the 11th hour here.”

Carle said that while federal officials want to impose additional rules, the sanctuary has no budget for expansion improvements.

Ige’s natural resources director, Suzanne Case, who has been on the job for two months, has said the state administration has no position, but her own perspective is that Maunalua Bay needs help.

“We look forward to the additional opportunity to hear and engage with the broad Maunalua Bay community on current natural resource issues,” Case said in a statement to the news media. “There’s been a lot of pressures on the bay in recent years. … There’s a longer conversation that’s much needed.”

Maunalua Bay has experienced major suburban development since the 1950s, with some communities situated on or near fishponds and wetlands that have been filled in for development. Others are near streambed areas fitted with canals that funnel runoff from streets and lawns into the bay. Hawaii Kai Marina was once Kuapa Pond.

The bay remains a habitat for marine species, including sea turtles, Hawaiian monk seals and humpback whales. But with 52 drainage ditches carrying chemicals and nutrients from urban areas, land-based sources of pollution have led to sedimentation on nearshore reefs and a degraded water supply, sanctuary officials say.

Also, the bay has become a hot spot for introduced species. For example, at least four species of introduced algae and invertebrates, such as sponges, have established themselves in the bay. Restoration efforts to remove the introduced algae and re-establish native species are ongoing.

In addition, a 2009 survey found Maunalua Bay had the smallest amount of fish biomass compared with more than 20 areas in the state. A team of Hawaii and Australian researchers said the pollution was giving rise to a breakdown of the coral reef and increased coastal erosion. The survey concluded that restoration of the reef would require an ecosystemwide approach.

A sanctuary proposal to increase protective areas for monk seals around Niihau and nearby Lehua Islet also has touched off opposition.

Fearing certain areas will be closed to fishing , opponents have gathered some 7,000 petition signatures against the expansion, said Makani Christensen, head of the statewide Hunting, Farming and Fishing Association.

“This is a statewide issue,” Christensen said. “This is not going to be a good thing for the state.”

Federal researchers have found that the endangered Hawaiian monk seal population is dwindling in the Northwest Hawaiian Islands, while the population is increasing in the main Hawaiian Islands.

Chow, the sanctuary superintendent, said nothing is final about her agency’s proposed expansion.

“This is not a done deal,” she said. “This is a draft proposal. The dialogue has just begun.”

In April, NOAA announced that it wants to see the now-thriving humpback whale removed from the federal endangered species list. Scientists estimate that there are 20,000 humpbacks in the North Pacific. An estimated 12,000 swim to Hawaii’s waters to mate and nurse their young, typically between September and March.

While they would no longer be shielded by endangered-species protection, humpbacks would still be covered by the Marine Mammal Protection Act, and local whales would be further protected by the sanctuary. The Marine Mammal Protection Act makes it illegal to harm or harass a humpback.

Following a round of public comments and hearings, NOAA hopes to designate all of the world’s humpback whales as members of 14 different populations. After being on the endangered species list for 35 years, Hawaii’s humpbacks, along with nine other humpback populations, would be removed.