Seeing vast numbers of insects cross from Asia to Europe has been a revelation for scientists
THINK OF MASS MIGRATIONS OF WILDLIFE and you might picture large animals on the move or huge flocks of birds. But tiny creatures can be equally impressive for the sheer numbers making long-distance journeys, reports Ecography. Such migrations are the focus of current PhD research by Will Hawkes, based at the University of Exeter. His work includes studying how some very small insects, such as hoverflies, make very long journeys as part of large migratory groups.
On a spring visit to north-east Cyprus, Will and his colleagues recorded 39 million migratory insects in just over one month, arriving from Asia at the tip of the Karpaz Peninsula.
“I had never seen anything like it before,” says Hawkes. “The sky was dark with insects and we were being pelted by migratory flies, to the extent that we had to shelter behind the car door.”
At one point, fellow researcher Karl Wotton reckoned the migration had reached a rate of 6,000 insects per metre every minute. Dragonflies and butterflies were part of the mass movement, but two-thirds of the insects were flies. These included hoverflies, some carrying orchid pollen, in what Hawkes describes as “cross-continental pollination”.
Such long-distance transfer of genetic material, with migrant insects acting as international couriers, could help plants to maintain diversity of genes. This could be crucial as environmental conditions alter, emphasising the importance of taking a global, holistic view of conservation.