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Do Asian Ladybugs Have a Positive Effect on the Ecosystem?

The Asian ladybug (Harmonia axyridis) is also known as the multicolored Asian ladybird beetle and has a wider variety of colors and spot numbers than any other ladybug species. Asian ladybirds were intentionally imported into the United States from northeastern Asia around 1916 as a natural form of insect control; subsequent reintroduction led to significant populations of the ladybird beetle near New Orleans in the late 1980s. Then, it took the ladybird population nearly 10 years to make its way as far north as Michigan.

Naturally Controls Insect Populations
- Like most ladybugs, Asian ladybugs feed primarily on plant-eating insects such as aphids, which is also their greatest contribution to the ecosystem. Aphids are a form of plant-eating lice that can devastate plant, trees and crops. In 1980 scientists attempted to reintroduce the ladybird beetle in New Orleans to control aphid populations amongst pecan trees. And more recently in 2001, this ladybug had naturally grown to high enough numbers that they saved Michigan soybean farmers thousands of dollars on pesticides by aggressively feeding on soybean eating aphids.
Protects Oxygen Making Plants
- The Asian ladybug moves to another location rather than over-exhaust a food source.
  
  Because the ladybird beetle can feed on close to 5,000 aphids during its lifetime, it is considered highly beneficial to gardeners and farmers as well. As a result of their ferocious appetite for eating plant-eating insects, they contribute to increased amounts of oxygen being produced because they prevent aphids and other soft-bodied pests from interrupting the photosynthetic tissues in many species of plants and trees. Although the Asian ladybird beetle will occasionally feed on fruit juices when insect populations are low, they are not reported as a crop-damaging insect.
Gardner's Friend
- The Asian ladybug's natural habitat includes foliage, leaf-bearing trees, shrubs and plants. Gardens, forests and orchards are among the most common places to spot these ladybird beetles as they live near their favorite food source (aphids). Asian ladybug larvae also help the ecosystem because they begin feeding on aphid eggs and larvae as soon as they hatch; therefore these ladybugs help control insect populations while in more than one stage of their life cycle.
Considerations
- To remove Asian ladybugs from the home, use a hand vacuum cleaner with a napkin placed over the bag hole, so that they can be released outside.
  
  Because ladybird beetles rarely feed on nectar and pollen and are always decreasing the plant-eating insect population, there are only a few ill effects of the ladybird beetle, but none are really concerned with the ecosystem. Homeowners can be overwhelmed by nesting ladybirds that come in only hibernate for the winter. When these ladybugs enter the home in large numbers, they can leave yellow stains of leg secretions where they nest. Pest control services generally will not remove ladybird beetles from home infestations because there is no guarantee that they will not return. But there are effective methods for easy removal.

Insects & Science