Ladybirds under threat

Ladybirds are named after Our Lady, the Virgin Mary. The red colour is said to represent the red cloak Mary was depicted wearing in old paintings. The seven spots are for the seven joys and seven sorrows.

The bright colours of ladybirds have evolved to act as a warning mechanism. Ladybirds are unpalatable to most predators and the warning colours advertise this. When ladybirds are attacked they ooze a horrid goo, called reflex blood, from their knees which contains toxins and tastes unpleasant. Not surprisingly this stops ants, birds and other predators from eating them.

There are over 5,000 species of ladybirds all over the world but only 46 in the UK. Some of these are very small and not spotted so there are only 27 which are likely to be found and easily recognised as ladybirds. Most species of ladybird are predatory – eating sap-sucking plant pests such as aphids. A few, such as the orange ladybird, eat mildews, and two species eat leaves. The ladybird was regarded historically as a magical animal – it foretold weather and happiness, cured toothache and increased potency.

Rumoured to have medicinal properties and some thought that ladybirds to be a cure for measles and colic.

The native ladybird (Coccinellidae), is under threat from the world’s most invasive ladybird species - the harlequin ladybird (Harmonia axyridis). To help the native ladybird, a national survey is taking place.

Originally from Asia, the harlequin ladybird was first spotted in the UK in September 2004. Since then many sightings have been reported, but these have mainly been confined to the south east of the UK. Much more information is needed to discover the true extent of the threat to the native ladybird.

There are 46 species from the native ladybird family (Coccinellidae) in UK and the arrival of the harlequin ladybird (see pic on left) is a potential threat to all of these. It is an extremely voracious predator which easily out competes native ladybirds for food. When their preferred food, of green fly and scale insects, is not available the harlequin turns on native ladybirds and other insects such as butterfly eggs, caterpillars and lacewing larvae.

The survey is calling for all gardeners, farmers, wildlife enthusiasts and anyone with a love of ladybirds to examine trees, bushes and plants and record all ladybirds, including the harlequin, they find. Scientists from the University of Cambridge, Anglia Polytechnic University, the Biological Records Centre and the Natural History Museum will use the results of the survey to gauge how widely the harlequin has spread throughout Britain.

Information can be submitted on line for the Harlequin ladybird survey or details can be sent to the UK Ladybird Survey, Biological Records Centre, Centre for Ecology and Hydrology, Monks Wood,Abbots Ripton, Cambridgeshire, PE28 2LS.

UPDATE: I emailed the Ladybird Survey to ask what action should be taken if we see Harlequin ladybirds and this is the reply:

"We do not recommend killing any ladybirds and although this is partly because of the risk of native species being misidentified as harlequins, also any that are killed will unfortunately make very little difference to the population.

Unfortunately there is currently no effective control method that will only target harlequins. However, research is being done to try and develop one (possibly using a pheromone that only attracts this species)."

Just hope they find something before the native ladybird is wiped out.