A swarm of Californian ladybugs is tens of kilometers wide on the radar

LOS ANGELES (Reuters) – A swarm of millions of ladybirds that rose in southern California this week to hunt aphids was captured on a radar screen in the form of a massive blob, officials said Thursday. .

The swarm of insects covered 130 km around the city of Hesperia, more than 110 km east of Los Angeles, said meteorologist Adam Roser of the National Weather Service's weather service ( NWS).

After a weather observer from Wrightwood City confirmed that it was ladybugs, the NWS office in San Diego released a video clip of the radar image on Twitter on Tuesday. showing an undulating mass.

The message received more than 1,000 retweets and generated comments such as "better than locusts" and "catch these aphids!" From the public.

"I thought it was pretty cool to see how we could interest all these different people in science," Roser said.

Ladybugs, also called ladybugs, are considered beneficial by gardeners who feast on aphids, spider mites and scale insects.

Ladybugs being small, a person standing under a swarm would see only points in the sky or, by far, nothing at all, said Ring Cardé, professor of entomology at the University of California, Riverside.

What caused the formation of the swarm?

One of the possible explanations is that a large population of ladybirds has scattered over a land in a mountainous region and that rising temperatures have caused massive migration, said Cardé.

"It's a little later than I would have thought earlier," said Cardé.

When they fly to the sky, ladybugs rely on the winds to transport them to the valleys, where they might find an abundant supply of aphids to eat, said Cardé. As the insects spread, the unlucky ones end up in the desert and die.

The ladybug movement in late spring follows a winter hibernation in the California mountains when they congregate in clusters so thick they can be shoveled, said Cardé. Insects try to stay alive under the snow.

High levels of moisture and precipitation this year have probably helped a large number of ladybugs survive in winter, said Cardé, which would explain a swarm of this size.

National Meteorological Service radars regularly capture birds, bats and insects from other parts of the country.

For example, bats often fly in caves around Austin, Texas, and appear on radar, while in Iowa, flies appear from time to time, said Jessica Schultz, Deputy Director of NWS Radar Operations Center in Norman, Oklahoma.