What can I do about harlequin ladybirds?

Harlequin ladybirds, Harmonia axyridis, were originally introduced to Europe to control pests like aphids and scale insects. However, they have now become established in the UK, and are often found in large congregations around windows, in winter. Watch this short video for expert advice from entomologist Richard 'Bugman' Jones on what you can do about them.