Conservation groups today filed a formal notice of their intent to sue the state if it does not take immediate steps to prevent bright lights at airports and harbors from killing imperiled seabirds on Maui and Lanai.

Earthjustice, an environmental law group filing the notice on behalf of the Conservation Council for Hawai‘i and the Center for Biological Diversity, said the Hawaii Department of Transportation is on 60-days notice.

The lights disorient seabirds who confuse them for moonlight that guide them out to sea, and instead end up circling them before crashing or falling to the ground from exhaustion.

Of particular concern to the groups are the impacts on threatened Newell’s shearwaters, endangered Hawaiian petrels, and band-rumped storm petrels.

“While there are other sources of bright light, HDOT’s airport and harbor facilities are the largest documented sources of seabird take on Maui and Lanai,” said Maxx Phillips of the Center for Biological Diversity. “They’re tall, free-standing, and exceptionally bright. This makes them attractive to threatened and endangered seabirds.”

The action follows an August 2017 suit alleging that the department failed to stop the deaths of the seabirds at its facilities on Kauai, Maui, and Lanai, in violation of the federal Endangered Species Act.

Following that suit, DOT followed through with a habitat conservation plan for Kauai’s facilities, according to Phillips, but has failed to do so for its airports and harbors on Maui and Lanai, prompting the notice.

As part of the process of securing an “incidental take” permit, DOT is required under the Act to develop a habitat conservation plan specifying how it will minimize and mitigate harm, she said, whether it be shielding or eliminating its bright lights or fencing nesting colonies to prevent predation.

Earthjustice says the department’s coastal lights, like those at Kahului Airport and Kahului Harbor, cause more fallout than inland lights, and are particularly dangerous for the seabirds.

“It’s clear that HDOT is operating its Maui and Lanai facilities in direct violation of the Endangered Species Act by harming and killing imperiled seabirds without an incidental take permit which is required under law,” said Phillips.

Bright lights have contributed significantly to the 94% decline in the population of Newell’s shearwaters on Kauai since the 1990s, the center said. They have also impacted Hawaiian petrels, whose numbers on Kauai have plummeted by 78% during the same time period.

Earthjustice attorney Leina‘ala Ley said DOT knows what to do since it has already taken steps to stop killing and injuring seabirds on Kauai.

“To save these birds from extinction, the department needs to implement similar measures immediately on Maui and Lanai,” she said. “There’s no time to waste.”

Conservation groups in past years have filed previous suits to protect imperiled seabirds, and prevailed.

On Kauai, for instance, the St. Regis Princeville Resort in 2010 agreed in a settlement to lower the lighting on its property as well as fund programs restoring populations of threatened Newell’s shearwaters following another Earthjustice suit.

That same year, The Kauai Island Utility Cooperative also admitted to violations of Endangered Species and Migratory Bird Treaty acts, and agreed to reconfigure power lines that cross birds’ paths between burrows and oceans, among other steps.

KIUC announced today it was installing reflective diverters on its electrical transmission and distribution lines to prevent seabirds from striking them while in flight as part of a process it began last year.

The largest Hawaiian petrel breeding colony is at Haleakala Crater on Maui, the center said, while the second-largest breeding colony is on Lanai. Additionally, a breeding colony of band-rumped storm petrels was recently discovered at Hauola Gulch on Lanai.

“We’re saddened that it may take another legal action to force the transportation department to stop ignoring its facilities’ role in the senseless deaths of Hawaii’s imperiled seabirds,” said Phillips in a news release. “There’s no reason why the state should be allowed to continue flouting the Endangered Species Act when simple measures could ensure bird safety.”