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Trillions of Insects

December 26, 2016

No other creatures match insects when it comes to sheer numbers of migrating animals.



Tracking insect migrations. I’m Bob Hirshon and this is Science Update.

Immense herds of wildebeest move en masse across the Serengeti plain; Alaskan salmon return to their natal streams to spawn; and Arctic terns circumnavigate the globe. These iconic migrations may be spectacular, but for sheer numbers, none can match the relatively overlooked migrations of high-flying insects. For ten years, University of Exeter ecologist Jason Chapman and his team used radar and floating nets to track the insects above southern England.

JASON CHAPMAN (Rothamsted Research/University of Exeter):

We found that on average during the summer months about 3 ½ trillion insects would be overhead.


The researchers report in Science magazine that over the years, seasonal movements to the north and south balanced each other out. But in any given year, they varied widely, impacting food webs, pest infestations, and crop pollination. I’m Bob Hirshon, for AAAS, the science society.

Story by Susanne Bard