After a lawsuit and lengthy settlement negotiations, the Grand Wailea resort on Maui has agreed to take steps to protect endangered Hawaiian petrels, a medium-sized, nocturnal seabird species also known as ‘ua‘u.

Hawaiian petrels are endangered due to threats from artificial lighting, introduced predators, historical hunting, feral ungulates, and collisions with cell towers, wind farms and utility poles, according to the Hawaii Department of Land and Natural Resources.

In the Grand Wailea case, environmental groups sued the hotel in February to force it to adjust its lighting. Plaintiffs argued that the resort’s bright lights attract petrels who then become confused and exhausted, falling to the ground and either dying or being attacked by predators.

With a settlement now in place, Grand Wailea has agreed to take protective measures, including dimming and adjusting its lights. The lawsuit by Conservation Council for Hawaii and the Center for Biological Diversity was argued by Earthjustice, an environmental law firm.

In a joint news release Tuesday, the Grand Wailea’s managing director said the resort has removed, replaced, shielded and dimmed lights across the property, among other steps, as part of its “deep commitment to protecting Hawaiian seabirds.”

“We will continue to monitor seabird activity on the property and are contributing to off-site projects to protect ‘ua‘u,” said J.P. Oliver.

Maxx Phillips, Hawaii director for the Center for Biological Diversity, said in the release that the settlement gives the petrel population “a chance at survival.”

The parties struck the agreement on Oct. 21 just days before Maui Mayor Michael Victorino signed into law Bill 21, which will restrict the amount of light pollution allowed on the island. The measure requires that all outdoor lighting fixtures, except for neon, must emit no more than 2% of blue light. Mercury vapor must no longer be used for new outdoor lighting fixtures.

All outdoor lighting, except for neon, must also be directed downward and be fully shielded.

The new law contains exemptions and takes effect July 1, with a three-year phase-in period. Most residential properties, except oceanfront homes, are exempt from the new lighting restriction as are evening sporting and cultural events and emergency services.

Kelly King, the South Maui Council Member who sponsored the legislation, said previously that dark night skies hold important cultural, astronomical and tourism-related values, all of which are threatened by artificial light pollution. The goal of her bill is “honor biodiversity and the culture of aina first in the community,” King said.