Have you noticed more ladybird beetles? What species are responsible for the swarm?
When I look at the radar in the news link above it’s not clear to me which radar blob they are talking about? They say that it’s in San Diego but I see a thicker blob over Hesperia in San Bernardino.
The photo they show in this article is a non-native Asian Lady Beetle. News people don’t know. The swarming lady beetles they are talking about are native Convergent Lady Beetles. I’m not good at reading radar, but it is a natural phenomenon as the beetles migrate to the mountain. http://ipm.ucanr.edu/PMG/FIG/neh-f8-2.html
Thanks @kimssight! Thanks for the link. So the swarm they are talking about is over San Bernardino County not San Diego county? I know news people always get this stuff wrong.
So to fill in the natural history a bit more specifically this is a swarm moving out of the desert into the San Gabriel and San Bernardino mountains?
Very cool. I’m always amazed when birds, insects and bats are detected on radar but it’s actually quite common I guess.
Convergent is really the only species that shows migration tendencies. I don’t think it is well-studied. The migrations are usually local (between elevations), but they do seem to spread. I’ve seen them on the offshore Channel Islands rarely, where they don’t appear to be established normally.