Harlequin Ladybirds– these large ladybirds give off a strong pheromone which allows them to detect each other and so gather in numbers at this time of year, hibernating in sheds, crevices, and inside our houses. The most invasive ladybird species in the world, they were introduced to the UK in 2004 to control aphids and have already become the most common species in our Sheffield garden. They bring a virus our native ladybirds are susceptible to, have multiple broods, and generally outcompete the natives. Harlequins have brown, not black legs, though their wing-cases can be variously coloured and spotted. Conditions: Wet and cloudy. Temperature: Max 5- Min 1C.