In 2016, the German Society for Nature Conservation released a report that shocked the scientific community: the country's flying insect biomass has decreased by 76 per cent over the past 27 years. Among the many ecological killers on the list, an often-overlooked killer is lurking under the roof of human civilisation - outdoor lighting systems. As we decorate our yards with sparkling wall lights, we may be creating a silent ecological carnage. From moths swooping on lights to disorientated migratory birds, from nocturnal insects that have stopped pollinating to endocrine-disrupting amphibians, artificial light sources are tearing apart the ecological web at night at a rate of 6% per year.
The navigational systems of phototropic insects have evolved over 300 million years to rely on moonlight polarisation, and cool white wall lights with wavelengths of 450-500nm can trigger fatal misdirection. Research at the University of Cambridge has found that an average LED wall light attracts and kills around 3,000 insects per year, including 32 pollinators and 15 pest natural enemies. To break this deadly cycle, solutions need to be found at the intersection of optical engineering and ecology, by banning short-wave blue light below 450nm (the most sensitive wavelength for insects), adopting amber LEDs (wavelengths of 590nm and above), and adopting 'insect-friendly' wall lights, which can reduce moth mortality rates from 97 per cent to 3 per cent for conventional lights. The use of Class III light distribution (beam angle <60°) and the installation of a light shield ensures that the light is projected only on the target wall. In addition, we ensure that the base brightness is maintained at 1-3 lux (equivalent to the light of a full moon), and that the light is automatically switched off 2 hours earlier in spring and summer (during the active insect season), and that a special protection mode is activated during the migratory season for migrating birds.
When we install a light on a patio wall, the beam of light will penetrate the border between human dwellings and the wild world, and may become a deadly blade or a protective boundary. Our modern outdoor lights black, black barn lights outdoor, wall pack with motion sensor and other outdoor lights use light patterns that minimise damage to insects and maintain the ecological balance.
