Insects in flight at night - A study investigates the influence of light on moth flight
Researchers at the University of Konstanz are investigating how light affects the behavior of moths. In the largest lab of the university, known as the Imaging Hangar, the night flight of moths has been studied for weeks. This is a unique study worldwide, said study leader Anna Stöckl. The analysis is expected to be published next year.
Moths with Mini-Markers
The experiments aim to provide new insights into how moths optimize their sensory perception under challenging light conditions. For this purpose, dozens of the small animals were marked with Mini-Markers. They are observed by 40 cameras in the Hangar. Spotlights and lamps ensure the appropriate light. "We want to understand how the moths change their flight when confronted with artificial light", explains the biologist. The study has been running since April, over a hundred moths have been observed.
As soon as the animals fly past a streetlamp, they have to deal with up to a thousand-fold stronger light intensity. "We know that from being blinded by a car headlight at night.", said Stöckl.
Helpless Cliché Moth
The moth is far better than its reputation. "We often depict our cliché moths as helpless animals that are completely at the mercy of our lamps.", said Stöckl. Light pollution is indeed a major problem for nocturnal animals, but the study is intended to show that moths can cope with it to a certain extent. "And if we can learn something from that for our lighting, to make it easier for the animals.",
Following small insects in nature is almost impossible. Experiments with cages cannot reflect the behavioral repertoire of the animals in nature. That's why the Hangar is "awesome". "We can only film ten meters by ten meters and five meters high in reality", said the study leader.
In the wild, one does not get images and data with such high resolution as in the lab. "And in the lab, one never gets the size of nature - in the Hangar, we have a kind of middle ground, where the animals can call on much more of their repertoire.", making the study unique worldwide.
Night-active Butterflies
When one thinks of moths, one often thinks of pests that damage clothes or eat sugar, explained the biologist. "But less than one percent of all moth species behave in any way as household pests." The vast majority can be imagined as moths that are night-active. "They drink nectar and pollinate plants as moths - and they are ecologically very important."
Moths may not have the same importance for agricultural plants as bees or honeybees, said Stöckl. But for many other plant species, they are essential. "If there were no moths, it would not directly harm our agriculture, but indirectly it could have consequences, if the ecosystem in which agriculture is practiced is disrupted.",
As to why moths are attracted to light, there are several theories. "It is very hotly debated why that is actually the case." One theory states that their visual system adapts to the brightness and they therefore remain. Another theory is that they take the light for the sky and therefore stay under it. Many people are working on this question.
- The University of Konstanz, located in the region of Baden-Württemberg, Germany, is where the pioneering study on moth behavior under different light conditions is being conducted.
- Anna Stöckl, the lead researcher at the University of Konstanz's Imaging Hangar, has marked dozens of moths with Mini-Markers for a more comprehensive analysis during their night flights.
- The unique lab setup at the University of Konstanz includes 40 cameras observing the moths' behavior, simulating various light conditions using spotlights and lamps during their night flight, including the exposure to streetlamps' intense light.
- The night flight study in Constanz aims to debunk the common misconception that moths are helpless creatures and demonstrate their ability to adapt to light pollution in cities, which could potentially inform future urban lighting plans to better support nocturnal insects.
