Zoologists from James Cook University attached trackers to moths and watched the insects’ mass migration. The scientists’ job was: published in the journal Science.
For a long time it was believed that migratory insects mostly fly where the wind blows. But scientists suggest that insects can choose favorable conditions for their travel.
In their study, the scientists wanted to learn how insects respond to changing wind conditions during flight.
For example, a migratory insect species, the death-headed moth, can maintain a perfectly straight flight path to compensate for high wind conditions.
The research team used genetic methods such as radar to identify food and water sources and provide information about where they came from, microtransmitters for tracking, and measuring isotope ratios in tissues.
“We tracked 14 moths for our study. “The scientists placed a small radio transmitter weighing less than 0.3 grams in each individual. A Cessna drone with receiving antennas tracked them as they migrated, pinpointing their exact position every 5 to 15 minutes.”
The team found that the moths fly in straight trajectories and plot an effective flight path to their target. Some of the longest trails reached almost 90km in four hours.
“The moths also showed different strategies for dealing with different wind conditions. They flew into the wind with a tailwind and headed towards their target, or changed direction slightly to maintain control of their trajectory. In adverse conditions, the moths flew low into the wind, adjusting their trajectories to stay on course. They increased it,” he said.
Scientists say understanding insect migration will help people manage endangered species as well as agricultural pests.