BOB HIRSHON (host):
A beetle battle. I’m Bob Hirshon and this is Science Update.
The Asian ladybird beetle was originally introduced into Europe to control plant pests like aphids. It’s very good at its job, but it’s also rapidly displacing native ladybird beetles. German scientists have now discovered how the invaders are killing off their European cousins. Molecular biologist Heiko Vogel of the Max Planck Institute for Chemical Ecology says the newcomers harbor extremely high levels of deadly parasites called microsporidia, but are themselves immune.
HEIKO VOGEL (Max Planck Institute for Chemical Ecology):
What happens is that all ladybird beetles eat other ladybird species’ eggs and larvae. When they do this with the Asian ladybird beetle eggs and larvae, they are dead after a few days. But the Asian ladybird beetle can easily feed on the the eggs and larvae of native ladybird beetles without any ill effects.
He says this has allowed the Asian ladybirds to spread rapidly around Europe. I’m Bob Hirshon, for AAAS, the science society.