LED lights could be dangerous for native moths

LED street lights will save money, but could come at a cost to native moths, says one environmentlover.

All older, yellow, highpressure sodium lighting in Auckland is to be replaced with new light-emitting diode (LED) street lights by about 2025. The first stage of fitting 44,000 LED residential street lights, has been under way for the past 18 months.

The lights use a third of the electricity the older style lights use, and last four to six times longer. They could save the city $32 million over their 20-year life.

But Geoff Reid wasn’t glowing about it, saying the lights could negatively affect New Zealand’s more than 2000 species of moth, as the tone of the light changes from golden yellow to white.

‘‘Moths are really important in our ecosystem. They are kind of these central key species because they not only provide food for birds, they pollinate plants and also provide food for other insects,’’ Reid said.

He said the new LED street lights, measured in kelvin, sit at more than 4000 while the current bulbs are around 2200. He said anything over about 2800 kelvin is bad for moths.

‘‘They extract moths out of the ecosystem. It wears them out and they also congregate in one area and what we’re finding is mice are just cleaning them up.’’

About 90 per cent of the moths are endemic to New Zealand with an estimated 400 species in Okura Bush near where Reid lives.

‘‘What we’re really concerned about is we have not had the chance to do any studies in Okura Bush. We could have 400 species in the bush and we don’t have any light pollution. So, what we’re facing with development, it’s going to have a negative effect,’’ Reid said. ‘‘But it’s not just about looking after Okura Bush, moths are so special to New Zealand. We should be saying we can’t have any of these type of lights.’’

Reid suggested, if LED lights

‘‘Moths are so special to New Zealand.’’

Geoff Reid

were used, the bulbs should have directional shielding and sensors should be considered. Street lights fall under Auckland Transport jurisdiction and an AT spokesman previously said AT believed LED lighting made the roads and footpaths safer.

He acknowledged the white light could take some people time to adjust to the difference.

AT implemented a policy in 2012 that all new lights on pedestrian-dominated roads would be LED.

SUPPLIED Geoff Reid is worried about the effect of LED lighting on New Zealand’s moths.