Hundreds of years before the invention of the light bulb, the stars showed the earliest Polynesian navigators the way to these islands. Wildlife, sea life and clusters of clouds guided these navigators toward land. Our wildlife and ecosystems, like these navigators, rely on the stars.

Now light pollution, needlessly brightening night skies, removes the stars from our sights — and from other species who rely on the stars for their own navigation and survival. It harms our wildlife (i.e., seabirds, sea turtles), coral, cultural activities (i.e., planting and fishing), crop growth, ecosystems, astronomy and related tourism. Glare at night impairs our vision — and compounds our eyes’ degeneration.

We need lights that guide us, not blind us.

The world’s skies are lit up like never before. Report after report is sounding the alarm on light pollution, but too few in leadership have heard it.

Hawaii is in a unique position to lead on policy to reverse these impacts. Maui and Hawaii County both enacted outdoor lighting ordinances over a decade ago. There have been ongoing policy conversations, such as the State’s Starlight Reserve Committee. We’re fortunate to have the beginnings of a policy framework from past legislative leadership to shield and direct outdoor lighting.

But the science has improved — not just for lighting options but in the source of the problem. Short wavelength, cool blue light has been the culprit identified across the planet in the degradation of ecosystems and species — including our own. Blue light floods most outdoor and indoor lighting — and our screens. We need this light during the day. It is the light of the sun. But at night, in excess, it is poisoning us.

Studies demonstrate the negative impact of blue, cool light — artificial light — at night (ALAN) upon human health. Two Harvard studies have sounded the alarm on increased cancer risks and blue light’s significant stresses to our bodies.

To avoid damage to ourselves and our ecosystems, pointing light where it’s needed matters. Outdoor lighting ordinances across the islands have begun to outline how to do this. But scientists now recommend using blue light filters on our screens and seeking warmer bulbs at night, those under 2700K (Kelvin) and less than 550nm (nanometers) causing the least damage. More public awareness — and policy change to address blue-light content — is urgently needed.

It’s time to update and create lighting ordinances that address cool, blue lighting to provide guidance to us all. Train county inspectors and translate these ordinances into an easy educational checklist for residents and businesses. Ensure that outdoor street lighting, overseen by the counties, is on the warmer spectrum of light or filtered — and points to where we need the light. The issue of light pollution should bring together a coalition across sectors, of those working on energy, public health, and caring for the aina and its people. We need their leadership, and Hawaii, as a state and across each island, can show the world the way.

For nocturnal creatures particularly — the honu and seabirds — human’s nighttime lighting sends the wrong signals and harms their survival rate. Like many, seabirds follow the light — the blue, cool light — as it resembles a food source and ancient code of survival. They become distracted by skyglow — light that could be shielded, but instead points needlessly to the night sky where neither we (nor the seabirds) need it.

These species and the aina we care for cannot turn off, shield or filter the lights.

So check the bulbs you purchase for their brightness. Shield all outdoor lighting and point it down — or off, if possible. Use motion sensors and timers. Try not to illuminate the shore or the sky. Close your blinds at night, particularly during the fall, to lessen our disparate impact on unwitting species. Encourage hotels and condo associations to spread the message to visitors.

Nancy Taylor is a strategist for the Maui Nui Seabird Recovery Project, a project of the Pacific Cooperative Studies Unit, through the Research Corporation of the University of Hawaii.