The Air Force has agreed to reduce exterior lighting at a mountaintop radar facility on Kauai to better protect endangered and threatened seabirds.

Following the decision, the Center for Biological Diversity, a nonprofit conservation group, said last week that it no longer intends to sue the Air Force.

The center said exterior lights at the Kokee Air Force Station caused the “fallout” — tumbling out of the air from exhaustion or striking a structure — of more than 130 endangered Hawaiian petrels, endangered band-rumped storm petrels and/or threatened Newell’s shearwaters in 2015. Most of the birds died, the center said.

The Save Our Shearwaters program said its staff handled a total of 471 downed seabirds on Kauai in 2015.

Predators such as cats, rats and barn owls are the primary cause of the seabirds’ decline, followed by impacts to power lines and then fallout from attraction to lights, according to Loyal Mehrhoff, the Center for Biological Diversity’s species recovery director.

An estimated 21,000 of the rapidly declining Newell’s shearwaters and 19,000 Hawaiian petrels are left on the planet, according to the group. About 170 to 220 breeding pairs of band-rumped storm petrels are thought to be on Kauai.

The center said the Newell’s shearwater and Hawaiian petrel are attracted to bright light at night, causing crashes onto the ground and sometimes death from injury or predation. For years, nighttime high school football games on Kauai have been limited because of concerns over stadium lights causing seabird injury.

Kokee Air Force Station was established in 1961 with the mission of detecting and tracking all aircraft operating in the area of the Hawaiian Islands. A long-range radar is capable of monitoring aircraft up to 250 miles from the site, which is at 3,500 feet elevation.

In 2015, there were reports of 43 Newell’s shearwaters and one Hawaiian petrel found in distress at Kokee on one day alone, according to a February U.S. Fish and Wildlife Service “biological opinion.”

The Air Force over the years has taken steps to try to reduce the losses, including a conversion from white and yellow exterior bulbs to green by February 2013, the Fish and Wildlife Service said. In 2015, perimeter lighting was repositioned.

The Air Force last June said it also had agreed to turn off exterior lights from April through December when birds are going to and from colonies.

However, at the end of June, the Center for Biological Diversity threatened legal action against the Air Force, saying it was violating the Endangered Species Act. The center said the Air Force had not updated its formal consultation with the Fish and Wildlife Service over the endangered and threatened seabirds.

In response, the Air Force reinitiated consultation and agreed to ongoing protective measures, the center said.

The service is “committed to protecting the threatened and endangered bird species that frequent the area around Mt. Kokee Air Force Station,” Col. Frank Flores, commander of the Pacific Air Forces Regional Support Center, which provides oversight for Kokee Air Force Station, said in an email. “We have collaborated closely with U.S. Fish and Wildlife Services over the years on this issue. We take environmental stewardship very seriously and will continue to partner with USFWS to protect these species.”

An exterior light blackout period will be in effect from April 1 to Dec. 30 annually, with a walking path outfitted with low-level lights expected to be installed to minimize seabird harm, Fish and Wildlife said.

“The green bulbs already installed in perimeter and building lighting infrastructure will continue to be used during the nonblackout period (Dec. 31 to March 31) when birds are not transiting to and from colonies over the installation,” Fish and Wildlife said in its new biological opinion.

The Air Force also agreed to continue to fund the Kauai Endangered Seabird Recovery Project’s monitoring of the Kokee site and to continue funding predator control efforts, the federal agency said.