Enemies of ladybirds
The bright colours of many ladybirds are to warn potential predators of their distastefulness
(aposematism). They exude a yellow substance (reflex blood) when attacked which
is rich in toxic alkaloids. Despite this, ladybirds do have enemies.
A 7-spot ladybird and the
cocoon of its parasitoid wasp
(photo: Mike Majerus)
A female phorid ovipositing
into a 2-spot ladybird pupa
The underside of a ladybird's elytron
infected with the sexually transmitted
mite Coccipolipus hippodamiae
(photo: Emma Rhule)
Some birds, such as swifts and swallows, which feed on the wing are immune to the
defensive chemicals of ladybirds. Ladybirds are also attacked and eaten by some
spiders, some of the larger predatory beetles and true bugs (Hemiptera), and their
eggs and larvae occasionally fall prey to other species of ladybird and to lacewing
Parasitoid wasps and flies
Several species of wasp and true fly lay their eggs on or inside ladybird larvae,
pupae or adults. When the eggs hatch, the larvae of these parasitoids feed inside
their ladybird host, exiting when fully-fed to pupate and emerge as adults outside
the ladybird, which dies as a result. These parasitoids include the wasp Dinocampus
coccinellae (Braconidae) - see picture, at least one species of scuttle-fly
(Phoridae), and a tachinid fly.
We are inviting people to look for the ladybird parasite Dinocampus coccinellae
and join the Ladybird Challenge.
Some mite species affect ladybirds, including sexually transmitted mites in the
genus Coccipolipus, which cause sterility in some ladybirds.
The soil dwelling fungus Beauveria bassiana is pathogenic to some ladybirds
species. The fungus produces infective spores which germinate and then penetrate
through the insect cuticle. This fungus then proliferates within the host until
it has utilised all available host resources at which stage it erupts back through
the host cuticle and produces more infective spores. Fungi in the genus Laboulbeniales
also affect some ladybirds
Some female ladybirds (including harlequins) are infected with a male-killing bacterium
(Spiroplasma), which kills male but not female embryos. This male-killing
causes an imbalance in population sex ratios in some parts of Asia. Work is currently
in progress to find out whether any of the harlequins that have arrived in Britain
are infected with this sex ratio distorter.