HONOLULU — Repairing coral reefs after boats run aground. Shielding native forest trees from a killer fungus outbreak. Patrolling waters for swimmers harassing dolphins and turtles.

Taking care of Hawaii's unique natural environment takes time, people and money. Now Hawaii wants tourists to help pay for it, especially because growing numbers are traveling to the islands to enjoy the beauty of its outdoors — including some lured by dramatic vistas they've seen on social media.

"All I want to do, honestly, is to make travelers accountable and have the capacity to help pay for the impact that they have," Democratic Gov. Josh Green said earlier this year. "We get between nine and 10 million visitors a year (but) we only have 1.4 million people living here. Those 10 million travelers should be helping us sustain our environment."

Hawaii lawmakers are considering legislation that would require tourists to pay for a yearlong license or pass to visit state parks and trails. They're still debating how much they would charge.

The governor campaigned last year on a platform of having all tourists pay a $50 fee to enter the state. Legislators think this would violate U.S. constitutional protections for free travel and have promoted their parks and trails approach instead. Either policy would be a first of its kind for any U.S. state.

Hawaii's leaders are following the example of other tourism hotspots that have imposed similar fees or taxes like Venice, Italy, and Ecuador's Galapagos Islands. The Pacific island nation of Palau, for example, charges arriving international passengers $100 to help it manage a sprawling marine sanctuary and promote ecotourism.

State Rep. Sean Quinlan, a Democrat who chairs the House Tourism Committee, said changing traveler patterns are one reason behind Hawaii's push. He said golf rounds per visitor per day have declined 30% over the past decade while hiking has increased 50%. People are also seeking out once-obscure sites that they've seen someone post on social media. The state doesn't have the money to manage all these places, he said.

"It's not like it was 20 years ago when you bring your family and you hit maybe one or two famous beaches and you go see Pearl Harbor. And that's the extent of it," Quinlan said. "These days it's like, well, you know, 'I saw this post on Instagram and there's this beautiful rope swing, a coconut tree.'"

"All these places that didn't have visitors now have visitors," he said.

Most state parks and trails are currently free. Some of the most popular ones already charge, like Diamond Head State Monument, which features a trail leading from the floor of a 300,000-year-old volcanic crater up to its summit. It gets 1 million visitors each year and costs $5 for each traveler.

A bill currently before the state House would require nonresidents 15 years and older visiting forests, parks, trails or "other natural area on state land" to buy an annual license online or via mobile app. Violators would pay a civil fine, though penalties wouldn't be imposed during a five-year education and transition period.

Residents with a Hawaii driver's license or other state identification would be exempt.

The Senate passed a version of the measure setting the fee at $50. But the House Finance Committee amended it last week to delete the dollar amount. Chair Kyle Yamashita, a Democrat, said the bill was "a work in progress."

Dawn Chang, chair of the state Board of Land and Natural Resources, told the committee that Hawaii's beaches are open to the public, so people probably wouldn't be cited there — and such details still need to be worked out.

Rep. Dee Morikawa, a Democrat on the committee, recommended that the state create a list of places that would require the license.

Green has indicated he's flexible about where the fee is imposed and that he's willing to support the Legislature's approach.

Supporters say there's no other place in the U.S. that imposes a similar fee on visitors. The closest equivalent may be the $34.50 tax Alaska charges to each cruise ship passenger.

Hawaii's conservation needs are great. Invasive pests are attacking the state's forests, including a fungal disease that is killing ohia, a tree unique to Hawaii that makes up the largest portion of the canopy in native wet forests.

Some conservation work directly responds to tourism. The harassment of wildlife like dolphins, turtles and Hawaiian monk seals is a recurring problem. Hikers can unknowingly bring invasive species into the forest on their boots. Snorkelers and boats trample on coral, adding stress to reefs already struggling with invasive algae and coral bleaching.

A 2019 report by Conservation International, a nonprofit environmental organization, estimated that total federal, state, county and private spending on conservation in Hawaii amounted to $535 million but the need was $886 million.

At the Diamond Head trail recently, some visitors said the fee would make the most sense for people who come to Hawaii often or who might be staying for several weeks. Some said $50 was too high, especially for those who view a walk through nature as a low-cost activity.

"For a large family that wants to have the experience with the kids, that would be a lot of money," said Sarah Tripp, who was visiting Hawaii with her husband and two of their three children from Marquette, Michigan.

Katrina Kain, an English teacher visiting from Puerto Rico, said she thought the fee would "sting" some people but would be fine so long as it was well-advertised.

"If tourists were informed about it, then they would be OK with it," she said. "If that was a surprise $50 fee, it would be a pretty lousy surprise."

The legislation says proceeds would go into a "visitor impact fee special fund" managed by the state Department of Land and Natural Resources.

Carissa Cabrera, project manager for the Hawaii Green Fee, a coalition of nonprofit groups supporting the measure, said this would ensure the state has money for conservation regardless of budget swings.

Mufi Hanneman, president and CEO of the Hawaii Lodging and Tourism Association, which represents hotels, backs the bill but said Hawaii must carefully monitor how the money is used.

"The last thing that you want to see is restrooms that haven't been fixed, trails or pathways that haven't been repaved or what have you — and year in, year out it remains the same and people are paying a fee," Hannemann said.