At a rather unusual time for a UBC farm visit on May 25, a group of about 20 people, mostly students, gathered at the gates at 9:30 p.m. for a walk called “Goth Butterflies — Shedding Moonlight on Nocturnal Insects.”
The event, part of the UBC Farm’s month of programming around the UN International Day for Biological Diversity, focused on how moths contribute to ecosystems through pollination much like bees and butterflies.
Unlike their more flamboyant daylight relatives, however, many moths do their work under the cover of darkness.
“Working at night, moths pollinate flowers and actively contribute to our food chain,” said Daphne Chevalier, an M.Sc. student in plant-insect ecology who co-facilitated the workshop. “Commonly misunderstood and often taken for pests, moths actually play an important role in the keeping of our biodiversity."
Since many species have co-evolved with nocturnal moths to reproduce via their specific mode of pollination, moths uphold biodiversity and are upheld by it in return. Biodiversity allows our ecosystems to better adapt to environmental shocks, including climate changes and disease. Genetic diversity within species increases their ability to develop adaptations to challenges, and the complex ecosystems that biodiversity upholds keep soils fertile, water clean and carbon in the soil.
Shedding light on nocturnal pollinators
The event served as an opportunity to learn about moths by engaging with them directly on the land.
Chevalier and other UBC graduate students in plant-insect ecology led an instructional workshop to learn about moth biology and their role in biodiversity, including examining specimens under microscopes.
Many plants, like highbush blueberries and strawberry bushes, have co-evolved with moths to attract their nocturnal attention. If a flower is pale-coloured and tubular, that might be a sign that moths, who are famously drawn to light, are its target audience.
As we examined specimens, Hannah Anderson, an MSc student in plant science, explained how their wings act as camouflage to evade nocturnal predators, such as bats.
The tiny scales that make up moths’ velvety wings provide defense against predators, allowing them to become less "visible" to bats' echolocation.
“When bats are hunting, they emit sonar calls that detect prey,” said Anderson. “The moths’ fuzz … absorb these calls. Think of a recording studio absorbing all the sounds into the walls. This is similar to what happens with moths, but they do it with their bodies.”
After the microscope workshop activity, we went for a night walk on the farm to explore moths and other insects. We found flying moths pollinating, as well as beetles and frogs.
Other areas of the farm are covered in bright white sheets put in place to attract moths and study their behaviour. For example, the white sheets enable researchers to examine moths’ pollen traces and work out the flowers they visited in the environment.
Moths to a flame
For the sake of moths and other night-dwellers, the UBC Farm turns off all artificial lights at 11 p.m. Artificial light is the current greatest threat to moths, as it disrupts their flight reflex and impacts their health and pollination work.
“Insects use light in diverse important ways,” said Matt Tsuruda, a PhD student in plant-insect ecology. “But in this increasingly industrialized world, artificial light is causing a lot of problems and complicating the ways that insects use light.”
Artificial light weakens moths’ survival and camouflage abilities.
“One study found that one in three of all moths that get attracted to a light … will die before the end of the night,” said Chevalier.
As dawn approaches, moths need to find a place to hide from predators during the day so they can rest.
“When areas are artificially lit, that impairs moths’ ability to assess whether a surface is going to mask their camouflage,” said Chevalier. “So they end up sleeping in spots that don’t match them at all and then they’re really easy to spot for predators.”
Limiting artificial light at night is essential in order to allow nocturnal insects, such as moths, to maintain their natural behaviour and life cycle. You can play a part in protecting them and biodiversity.
Chevalier recommended three simple ways to protect moths: “Reduce light at night, put sensors at night to avoid unnecessary lighting and make sure porch or outside lights are facing down to keep insects from being led to artificial light and let them do their work and pollinate.”
Moths teach us that change is beautiful — from a crawling larvae, they develop into a flying creature. Each creature is important for maintaining our ecosystem and biodiversity. You, like many other creatures, are part of the ecosystem and can participate in its shaping.