Harlequin Ladybird

• It was introduced deliberately as biological control for aphids and scale insects, and ended up an invader: it is established in at least 59 countries outside its native range.
• It is an intraguild predator: as well as aphids it eats the eggs and larvae of other ladybirds, including native ones.
• An eleven-year study in eastern England recorded native ladybirds falling from 99.8% of the total in 2006 to 30.7% in 2016.
• The European species most at risk is the two-spot ladybird, Adalia bipunctata.
• It has spread to every continent except Australia and Antarctica in about thirty years.

Skeleton type

Invertebrate - chitin exoskeleton (insect)

Habitat and environment

Deciduous woodland, crops, orchards and gardens; in autumn it gathers en masse to overwinter, often inside buildings

Gestation / incubation

Development from egg to adult requires 15 to 25 days depending on the temperature and the availability of food

Litter / clutch size

20 to 30 eggs a day and between 1,600 and 3,800 eggs per female over her lifetime; one comparative study recorded an average of 1,029 eggs per female

Sources consulted: Wikipedia (es): Harmonia axyridis · Landcare Research / Plant & Food Research (Nueva Zelanda) · Pesquisa Agropecuaria Brasileira 48(11), 2013 · Compilacion sobre ecologia de Harmonia axyridis basada en la Global Invasive Species Database · Buglife, ficha Harlequin ladybird

Best time: The adults begin to be active when the temperature reaches 12 °C; two or more overlapping generations a year and overwintering in groups, often inside buildings in autumn