Ladybirds are voracious aphid munchers and so are a great help in our gardens. In the UK we have 26 species of true ladybirds but if the similar leaf-beetles are included the figure rises to a surprising 46.
The pretty red colour of our most common ladybirds makes them attractive insects. This bright red also acts as a warning to birds, “eat me and you’ll find I contain poison”, or words to that effect. If you handle a ladybird you will find they leave a stain on your fingers. The stain is actually caused by blood which oozes from the ladybird’s leg joints. Known as reflex bleeding this blood contains unpleasant tasting chemicals and is another warning to predators. Reflex bleeding takes a lot out of a ladybird so although it may be tempting to pick them up they really are best left alone.
Adult ladybirds will hibernate over winter in large groups crammed together beneath windows or in cracks in wooden sheds. To encourage ladybirds in your garden provide them with somewhere to hibernate, such as a Ladybird Tower or woodpile.
In spring the ladybirds will emerge from hibernation and the females will each lay about 200 eggs. They lay these eggs on the underside of leaves infested with aphids. This means the larvae will have ready access to food with a single ladybird larva eating hundreds of ladybirds.
After about 3 weeks the larvae will turn into pupae and in early summer the young ladybirds will emerge. They will hibernate in the autumn and breed the following spring with a life span of up to 3 years.
A new species of ladybird has recently arrived in the UK, the Harlequin. This highly invasive ladybird puts our native species in jeopardy.
For more information and for help in identifying the different species, including the Harlequin, please visit the UK Ladybird Survey website at http://www.ladybird-survey.org/harlequin.aspx