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Why Do Ladybugs Swarm?

ladybug swarm
J Doll, CC BY 3.0, via Wikimedia Commons

Every winter, without fail, I would have a small gathering of ladybugs in my bedroom. It turns out ladybugs don’t just form these small groups. They can create huge swarms in the thousands, but why do ladybugs do this? Find out in this article.

Why do ladybugs swarm?

Ladybugs gather in large groups during the winter months from November – February. This behaviour is called aggregation. This allows the ladybugs to regulate their internal body temperatures, enhance their defence, and share mates and resources.

Ladybug Swarm 80 Miles Wide

The National Weather Service’s radar is usually meant to monitor the weather rather than picking up vast numbers of ladybugs. In June 2019, the radar picked up a swarm of ladybugs 80 miles wide over San Diego County.

This was a colossal ladybug bloom. Scientists said they were travelling to a higher elevation in search of food. They were spread out so they were not packed together like a dense cloud. They appeared more like little dots in the sky.

Ladybugs are helpful little insects that are great for your garden because they help control pests such as aphids, which can destroy plants and transmit viruses. Ladybugs can consume hundreds of aphids per day and thousands in their lifetime. Ladybugs can be attracted to the garden with pollen-rich blooms and somewhere to overwinter.