Hawaii’s spinner dolphins have become a hot tourist commodity.

It’s easy to see why; the dolphins, known for their sleek beauty and spectacular leaps, are tailor-made for sightseeing.

They rest and socialize in waters close to shore during the day, at times and places convenient for commercial tour boat operations.

They congregate in well-known locations, in clear water with sandy bottoms, giving snorkelers and other swimmers an aquarium-quality view.

And unlike humpback whales, they remain here year-round.

So an activity once limited to a few adventurous swimmers with local knowledge has become, sadly and inevitably, a booming and heavily promoted business.

So it makes sense that the National Marine Fisheries Service (NMFS), concerned that humans are disrupting the dolphins’ natural resting behavior, wants to restrict activity around the wild animals.

The NMFS would prohibit swimming with or otherwise approaching within 50 yards of the dolphins by any means, including tour boats, kayaks and drones.

The proposed rules would apply within two nautical miles of the Hawaiian Islands and in waters between Lanai, Maui and Kahoolawe.

The proposed regulations are good ones: They strike a necessary balance between commercial interests and protecting the marine mammals.

The dolphins feed offshore at night, returning to nearshore protected waters during the day. They use the time to sleep, socialize and otherwise recover from their evening’s labors.

Research conducted at such dolphin habitats as Makua Bay on Oahu and Kealakekua, Honaunau and Kauhako bays on Hawaii island, suggests that dolphins change their behavior in response to human presence, possibly from stress.

Whether this human activity actually is harming the dolphins by disrupting their rest has not been proven; but the best available scientific evidence, along with common sense, suggests it easily could. And such harassment violates federal law.

In any event, it would be unwise to allow this commercial activity to continue and expand unchecked until harm can be proven conclusively.

A draft environmental impact statement prepared by NMFS estimated that in 2014, more than 100 tour boat and kayak companies provided customers the opportunity to view the dolphins; as many as 70 provided direct interactions.

“Researchers have observed up to 13 tour boats at a time in some locations, with vessels jockeying for position on a single spinner dolphin group and more than 60 swimmers in the water to closely interact with the dolphins at once,” the DEIS said.

This activity is understandable. Tour operators often guarantee their customers a dolphin encounter (or get a free voucher for another trip), and may communicate with other operators to locate the schools. Everyone wins, except the dolphins.

Tour operators worry that the 50-yard restriction would ruin their business. True, if it depends on swimming with dolphins. But the rules would not prohibit observing the dolphins, only from getting too close. They also provide exceptions for inadvertent encounters closer than 50 yards.

Tour operators also argue that, as far as they can tell, the dolphins are unaffected by the presence of humans — but that sounds more like wishful thinking than reliable science. Unlike captive dolphins trained to interact with people, the spinners are wild animals in their own habitat; dodging snorkelers with cameras is not a natural behavior.

NMFS will be accepting public comments on the proposal through Oct. 23.

The agency will also hold public meetings beginning Sept. 7 in Kealakekua, Hawaii island. Meetings on Oahu will be on Sept. 27 at Roosevelt High School and Sept. 28 at Waianae High School. Visit http://www.fpir.noaa.gov/PRD/prd_spinner.html for more details.