This thoroughly enjoyable, and highly informative, walk was rounded off with excellent refreshments in the Black Cat restaurant kindly remaining open for our benefit
Gwyneth and Tony Peters
LADYBIRD, LADYBIRD, FLY AWAY HOME…
…Don’t eat our natives, leave them alone.
If only it was that simple! But the Harlequin Ladybird Harmonia axyridis from eastern Asia will not be that easy to get rid of. It has been described as the most invasive ladybird on Earth. It was introduced into many countries as a biological control agent against aphids and scale insect infestations, but like many such schemes, they go awry when the alien escapes and is itself not controlled by its native predators, or can out-compete native species. It is now the most widespread ladybird in North America, and arrived in the UK in the summer of 2004 from, it is thought, northwest Europe and Canada in imported vegetables and flowers. It has been found mainly in the southeast of England and East Anglia, but is likely to spread north and west.
Wherever it came from, many ecologists are concerned about its effect on our native wildlife. The invader is an aggressive voracious predator with a huge appetite for greenfly (and other types of insects, eating butterfly eggs, caterpillars and lacewing larvae), and our native species will be in direct competition with it in the search for aphids. Some will simply not cope. However, harlequins also eat other smaller ladybirds, dealing a double blow to our native species.
Harlequins not only threaten other insects. They tend to cluster in houses in the autumn seeking places to overwinter, and may stain soft furnishings with their exudates of yellow reflex blood. They may also bite people in the late summer as they run out of aphid prey. They feed on fruit juices as they fuel up for the winter, blemishing many soft fruits and reducing the value of the crop.