The Times Australia
The Times World News

.

Want to help our precious nocturnal bugs during Matariki’s longer nights? Turn the lights down low

  • Written by Janice Lord, Associate Professor in Botany, University of Otago
Want to help our precious nocturnal bugs during Matariki’s longer nights? Turn the lights down low

In a world increasingly affected by light pollution, we can take time during the shorter days and longer nights around Matariki to appreciate the superpowers of our nocturnal bugs.

As diurnal creatures, our world view is strongly biased towards a daytime perspective. We pay more attention to events happening during daylight, and sometimes overlook the fascinating world of nocturnal insects.

Human eyes are very poor at gathering enough light particles – photons – to see clearly at night. We need the light of a full moon to have much hope of navigating safely.

For millennia, then, we’ve used fire and more recently electricity to artificially light up the night. Nocturnal insects now deal with a very different nightscape than they did even a century ago.

It’s been estimated that 23% of the world’s land area is affected by light pollution. This is thought to be one of the factors contributing to insect decline worldwide.

Recent research suggests about a third of insects attracted to artificial lights will die by morning, often from exhaustion[1]. If those insects have been prevented from mating and laying eggs, there are huge implications for population survival, as well as for ecosystem functions such as pollination and biocontrol.

Glow worms inside the Waitomo Caves.
Glow worms are the larvae of fungus gnats and can make their own light. Getty Images

Nocturnal superpowers

Many bugs are more active at night, most likely to avoid daytime predators. Some can also make their own light. New Zealand glow worms, the larvae of fungus gnats, use bioluminescence to hunt[2].

Elsewhere in the world, some flying beetles are commonly known as fireflies due to the fiery crackles of light they produce to confuse and ward off predators[3].

Moonlight is roughly one million times less intense than sunlight. But nocturnal insects can navigate, see colour and detect movement with only the light from the stars and moon[4].

This superpower is due in part to their incredible compound eyes. These are made up of millions of tiny lenses that each capture the maximum amount of light from a small field of view, and focus it onto a bundle of photoreceptors.

The ability to make sense of very low light levels is also due to higher contrast sensitivity at the expense of detail. Moths in particular boast several adaptations that aid in navigating and perceiving[5] in low light.

Many New Zealand moths are nocturnal, and their eyes are largely specialised for motion detection, differentiating between intensities of light rather than distinct wavelengths.

Compared with day-flying butterflies, which can perceive more detail and differentiate wavelengths as colours, moths have evolved greater perception of contrast and large-scale changes in their visual environment. But this comes at the expense of spatial sensitivity[6].

LED lights and moths

Contrary to myth, nocturnal insects do not fly around artificial lights because they confuse them with the moon or stars. Recent research, filming moths with high-speed cameras, found they use moonlight and starlight to differentiate between “up” and “down” as they fly.

Their erratic flight around your outside light is actually due to them trying to orientate themselves[7] to a nonexistent horizon.

The colour of artificial lights can also affect how attractive they are to nocturnal insects. In recent years, Dunedin (like many cities around the world) has been replacing old high-pressure sodium bulbs in street lights with LEDs that use less energy and have lower maintenance costs.

But this hasn’t been so great for night-flying insects. Moths can detect light wavelengths as low as 300 nanometres (invisible to human eyes) and as high as 700nm (orange-red to humans). But many have a peak sensitivity at 400nm (human blue).

The old sodium bulbs produced a warm orange or golden glow. But the brighter LEDs commonly produce a cool white light at the blue end of the spectrum, right at peak sensitivity for many moths. Warmer LED lights (with a lower colour temperature) can be less attractive to flying insects, and also help reduce light pollution across the city.

Dunedin cityscape at dusk
Dunedin by night: new LED lighting has not been kind to nocturnal bugs. Getty Images

Helping our night bugs

Closer to home, we can make a difference for our own backyard bugs (and other nocturnal and twilight fauna) by reducing light pollution[8].

Something as simple as closing curtains at night will discourage flying insects from crashing into windows – and getting inside!

Using motion-activated outside lights, rather than having them permanently on, can reduce the deaths toll in your local moth populations. And selecting warmer coloured light bulbs and fairy lights will make them less attractive to nocturnal insects.

Finally, turning off your lights and venturing outside will not only give your backyard bugs a break, but also help you appreciate the wonders of the night sky at Matariki.

References

  1. ^ often from exhaustion (www.sciencedirect.com)
  2. ^ bioluminescence to hunt (www.nzgeo.com)
  3. ^ confuse and ward off predators (news.ncsu.edu)
  4. ^ light from the stars and moon (royalsocietypublishing.org)
  5. ^ navigating and perceiving (www.linkedin.com)
  6. ^ expense of spatial sensitivity (www.cell.com)
  7. ^ trying to orientate themselves (www.scientificamerican.com)
  8. ^ reducing light pollution (darksky.org)

Read more https://theconversation.com/want-to-help-our-precious-nocturnal-bugs-during-matarikis-longer-nights-turn-the-lights-down-low-232701

Times Magazine

Headless CMS in Digital Twins and 3D Product Experiences

Image by freepik As the metaverse becomes more advanced and accessible, it's clear that multiple sectors will use digital twins and 3D product experiences to visualize, connect, and streamline efforts better. A digital twin is a virtual replica of ...

The Decline of Hyper-Casual: How Mid-Core Mobile Games Took Over in 2025

In recent years, the mobile gaming landscape has undergone a significant transformation, with mid-core mobile games emerging as the dominant force in app stores by 2025. This shift is underpinned by changing user habits and evolving monetization tr...

Understanding ITIL 4 and PRINCE2 Project Management Synergy

Key Highlights ITIL 4 focuses on IT service management, emphasising continual improvement and value creation through modern digital transformation approaches. PRINCE2 project management supports systematic planning and execution of projects wit...

What AI Adoption Means for the Future of Workplace Risk Management

Image by freepik As industrial operations become more complex and fast-paced, the risks faced by workers and employers alike continue to grow. Traditional safety models—reliant on manual oversight, reactive investigations, and standardised checklist...

From Beach Bops to Alpine Anthems: Your Sonos Survival Guide for a Long Weekend Escape

Alright, fellow adventurers and relaxation enthusiasts! So, you've packed your bags, charged your devices, and mentally prepared for that glorious King's Birthday long weekend. But hold on, are you really ready? Because a true long weekend warrior kn...

Effective Commercial Pest Control Solutions for a Safer Workplace

Keeping a workplace clean, safe, and free from pests is essential for maintaining productivity, protecting employee health, and upholding a company's reputation. Pests pose health risks, can cause structural damage, and can lead to serious legal an...

The Times Features

Tricia Paoluccio designer to the stars

The Case for Nuturing Creativity in the Classroom, and in our Lives I am an actress and an artist who has had the privilege of sharing my work across many countries, touring my ...

Duke of Dural to Get Rooftop Bar as New Owners Invest in Venue Upgrade

The Duke of Dural, in Sydney’s north-west, is set for a major uplift under new ownership, following its acquisition by hospitality group Good Beer Company this week. Led by resp...

Prefab’s Second Life: Why Australia’s Backyard Boom Needs a Circular Makeover

The humble granny flat is being reimagined not just as a fix for housing shortages, but as a cornerstone of circular, factory-built architecture. But are our systems ready to s...

Melbourne’s Burglary Boom: Break-Ins Surge Nearly 25%

Victorian homeowners are being warned to act now, as rising break-ins and falling arrest rates paint a worrying picture for suburban safety. Melbourne residents are facing an ...

Exploring the Curriculum at a Modern Junior School in Melbourne

Key Highlights The curriculum at junior schools emphasises whole-person development, catering to children’s physical, emotional, and intellectual needs. It ensures early year...

Distressed by all the bad news? Here’s how to stay informed but still look after yourself

If you’re feeling like the news is particularly bad at the moment, you’re not alone. But many of us can’t look away – and don’t want to. Engaging with news can help us make ...