The Unseen Impact of Cool-White LEDs on Bees and the Night-time Environment

I generally like to sit outside at night on the patio. Over the last few years, I've noticed that almost every night, a single bee will fly in and around the LED light before dying. It’s annoying but also got me thinking recently. I don’t ever remember bees hanging around lights when I was younger in the 1980s and 90s. Moths, often. other insects, sure. But never did I see bees.

This observation led me to a bit of a light bulb moment (pun intended). I started considering what had changed. The answer hit me when I looked up at the LED light I now use. It's a cool-white LED, which emits light at a particular frequency, predominantly at the blue end of the spectrum. This is quite different from the incandescent lights we used to have, which leaned more towards the red-orange end of the spectrum - Outside the Bees normal light sensitivity.

Above: a) Graph Depicting Spectrum of Cool & Warm LED and Incandescent bulb.
b) Sensitivity to various parts of the Spectrum for Humans and Bees.

It turns out that bees are more sensitive to blue and ultraviolet light. Attracted to flowers that reflect the spectrum from Blue to UltraViolet. This sensitivity is likely why they’re drawn to the cool-white LED light. In contrast, incandescent lights, with their warm glow, don’t have the same effect on bees. So, my conclusion is that cool-white LED lighting is bad for bees and the broader ecology they represent. These lights might be contributing to the harm of bee populations, which we know are already under threat from various other factors.

This brings up an important consideration for outdoor lighting. To help protect bees, it would be better to use warm-white LED lights, incandescent lights, or even fluorescent lights, which emit light in a more yellow-green spectrum. This small change could make a significant difference.

Bees play a crucial role in pollination, which is vital for the growth of many crops and plants. Their decline could have severe consequences for our food supply and natural ecosystems. By making a conscious choice in our lighting, we can create a more bee-friendly environment, contributing to their preservation.

Switching to more bee-friendly lighting is a simple step that can have a big impact. It's a small change in our daily lives but one that aligns with broader efforts to support and protect our environment. Next time you’re choosing outdoor lighting, consider how it might affect the local bee population. Your choice could help ensure that these essential pollinators continue to thrive.

So, as I sit on my patio and watch the night unfold, I’m reminded that even in the small details, like the type of light bulb we use, we have the power to make a positive impact on the world around us. Let’s choose wisely and do our part to protect the bees and, by extension, our planet. By switching to more friendly outdoor lighting, we can help protect bees and other species highly sensitive to the cool-white lighting.