The Seven-spot Ladybird is a member of the beetle family Coccinellidea, in the Order Coleoptera, and is our most common ladybird. It is one of 25 species found in this country - all have different colour and spot combinations to warn off predators. They are named after the Virgin Mary (Our Lady's Bird) - the red colour is said to represent the red cloak, worn by Mary in old paintings, the seven spots are for the seven joys and seven sorrows.
They were thought to have medicinal properties, a cure for measles and colic; tooth-ache was treated by mashing up a ladybird and putting the pulp into the cavity.
Most species of ladybird are predatory - eating sap-sucking plant pests, particularly aphids. Although we do not want the aphids there needs to be some around to keep the ladybirds alive. During the drought of 1976 the population of aphids declined sharply and this led to swarms of ladybirds searhing for food. If attacked they can secrete unpleasant oils from joints in their legs which deters ants and birds from eating them.
Hibernating throughout the winter in plant debris, dry cracks and crevices, ladybirds wake-up in April and seek partners to mate. They have three stages of development, egg, larva and pupa, before becoming adults. Eggs take about 4 days to hatch depending on temperature. The larvae (above right) moult 3 times and after about 3 months, depending on the availability of aphids, they pupate - more than 300 are usually eaten by a larva. The pupa is more rounded in shape but resembles the larva, and is usually attached to a leaf. After about a week the pupal skin splits along the back and the adult emerges, feeds for a few weeks and finds a place to hibernate.
So this is a definite garden friend and should never be endangered. If allowed to do their work they will see off most infestations of aphids after a while. They need a supply to sustain them, so if every aphid is eradicated with insecticides, the ladybird will starve. Left to their own devices a natural balance will emerge.
Supply them with somewhere to hide by placing horizontal bunches of dead, hollow stems in the bottom of hedges or another sheltered, dry spot. Special 'bug' houses are produced commercially for use in the garden. When clearing up around herbaceous plants in winter they can often be found hibernating in the debris so care should be taken when handling it. Also watch out for the bright Red Lily Beetles which hide in similar areas - these of course should be crushed, but take a second look before doing so.
There is now a great threat to our native Ladybirds from an Asian cousin known as the Harlequin Ladybird, Harmonia axyridis. It has been used as a biological control for aphids, but has a voracious apetite and having escaped to the wild it is now over-running native species. They can have several generations in a season, unlike our native species which have one. In North America, where it was introduced in 1988, it is now the dominant species. When the aphids and scale insects run out it feeds on caterpillars and lacewing larvae, and even on Ladybirds themselves.
The Harlequins are more round and slightly larger than most native species and can have a number of colours (hence the name), usually orange with between 15 to 20 spots or black with 2 to 4 orange or red spots. Just behind the head is a whitish scale with a black squiggle like an M.
They are now widespread on mainland Europe where they were used as a biological control, in 2004 they were first spotted in Essex and there have been sightings all over the South East of England. In March 2005 a survey was launched to raise awareness of the threat.
Another threat to our Ladybirds is a fungal infection by Hesperomyces virescens usually transmitted during mating, but can also be transferred by contact when they clump together for shelter in the winter. It manifests as yellow finger-like projections usually on areas that come into contact such as the backs of females and the underside of males. Badly infected individuals can be covered with the small yellow spines.
The fungus is in the Laboulbeniales group which infect many insect species and Hesperomyces virescens can be found in other species. The 2-spot Ladybird is known to carry this infection, but it has also been found in the Harlequin and mainly in the south of England. It is not certain how harmful the infection is, but it may affect the reproductive capacity or the lifespan of the insects.
