Invasive harlequin ladybugs threaten crops and flowers

Invasive harlequin ladybugs threaten crops and flowersLadybugs, or ladybirds as they’re referred to outside of the U.S., are normally received warmly by farmers and gardeners. But the harlequin ladybird might not be worth such a warm welcome after all, according to a new study from England.

“The rapid spread of this species has inspired biologists to study the process of invasion on a global scale,” warned Centre for Ecology and Hydrology researcher Helen Roy in a press statement. Ladybirds are a breed of spotted beetle that originally came from Asia, but can be found in various parts of the United States, where they’re commonly known as ladybugs. They can also be found in certain parts of Canada and Europe.

The harlequin ladybird, known by the scientific name Harmonia axyridis, stands out as being an especially invasive species. The beetle has made its way to a few parts of South America, and can also be found in certain northern and southern African countries. In Europe, the species has likewise proven to be quite invasive. In the Netherlands, it took a mere four years after its introduction for the beetle to spread across the country, while in Russia, the harlequin ladybird had first appeared in the western part of the country in 2010. The beetles have since appeared close to 200 miles toward the south.

While farmers and gardeners are happy that ladybirds are useful in protecting their crops and flowers from pests such as aphids, experts believe that the main take-home thought of the ladybird invasion is ecological balance. Researchers are working on ways to determine the ladybird’s natural enemies that may be useful in controlling the beetle’s population. For example, the parasitic wasp Dinocampus coccinellae can be found in different parts of the world, and counts ladybirds among their top hosts.

The researchers believe that more studies and observations would be needed to determine the impact of the ladybird on the ecosystem, and how far its range has expanded.