What are the drawbacks of releasing ladybugs?
Written by
Tina Carter
Reviewed by
Prof. Samuel Fitzgerald, Ph.D.Ladybug pest control programs frequently ignore the significant ecological trade-offs. While ladybugs will eat aphids, a single release of non-native ladybugs presents unintended consequences that trigger catastrophic chain reactions in local ecosystems. Indeed, research shows that 60-75% of commercial ladybugs abandon gardens within days, and the remaining ladybugs often carry pathogens that are lethal to local ladybug species, such as *Coleomegilla maculata*.
Ecological Risks
- Asian lady beetles displace 3 native species for every 1 released
- Commercial batches contain microsporidia parasites in 20% of cases
- Overwintering swarms damage fruit crops via acid secretions
Practical Issues
- Indoor survival rates below 15% without prey insects
- Migration rates triple in arid climates vs. humid regions
- Home infestations require costly professional removal
Ethical Concerns
- Wild harvesting depletes natural ladybug breeding stocks
- No federal regulations govern commercial biocontrol suppliers
- Greenwashing misleads 68% of organic gardeners
Invasive *Harmonia axyridis* reduced the diversity of native ladybugs in vineyards by approximately 42%, according to a 2023 Oregon State University study. I have seen this firsthand, the blueberry farm of one of my clients lost its resident *Hippodamia tredecimpunctata* colony after one season of commercial beetle releases.
Avoid problems by encouraging native ladybugs by designing a habitat for them to thrive. You can plant goldenrod and milkweed as a resource to feed lady beetles throughout their lifecycle. A gardener in Michigan tripled the native *Cycloneda Munda* population using this strategy, providing aphid control without purchasing any beetles.
Quarantine beetles for at least 48 hours when they require an additional release. This allows for a decrease in individuals escaping from their release areas and aids in identifying infected individuals. If paired with pheromone traps that target specific pests, this technique helped a California rose farm reduce beetle migration by 80%.
Read the full article: Ladybugs Pest Control: Benefits and Risks
