Saturday, September 19, 2009

More Ants on the Wing

In the yard beside our house, I found another ant colony sending off its fertile adults. Here are a couple of the young winged queen ants ready to take off on their mating flights.

This was a large colony and the mass of ants covered an area about eight feet across. I made several counts and estimated 32 queens taking off per minute. This is almost 2,000 ants taking wing each hour and I witnessed the activity for several hours on two consecutive days. Of course not all of those will found new colonies. Dragonflies took hundreds as the swarm drifted out across the field and in the evening, bats replaced the dragonflies.

This ant is Lasius umbratus, sometimes called the Citronella Ant because of the lemony fragrance they emit when disturbed. When not sending off breeding swarms, they spend most of their time beneath ground. It’s not uncommon to find them beneath rocks or logs. I’ve seen these ants move into buildings during the winter and release breeding swarms inside during February or March.

Evacuating thousands of winged colony members can be a bit chaotic. I didn’t see any winged males leaving from this colony. Genetically it makes sense not to have males and females take off at the same time. It would be best for the females to mate with males from a distant colony.

The basic goal of the winged individual is to climb to a point where it can spread its wings and fly. Flying ants are rather clumsy and any obstacle in their take off zone will cause them to crash back to the ground. Ideally, the queen will only take off once and will land fertilized and ready to start a new colony.

Usually there’s so much confusion that it’s a wonder any ants ever make it into the air.


  1. I had no idea the female ants had lavender on them. In the close-up they have very pretty faces and coloring. I've never looked that closely at one. I will now.

  2. Hi Kelly - I think the lavender coloring is actually a reflection of the blue sky. Sorry, I didn't mean for the photos to be misleading. Without the reflection, the color is more copper or burnt orange. Still a pretty face though.

  3. Hi Steve, I am new to your blog-Thank You! I was scrolling older entries, and now know the name for the lemony scented ants I only see after I smell them! They are tiny,(the workers,anyway), and cats love them,in the same way catnip draws them, in case you don't know.I wonder if any native animals are drawn, or only repelled, by their scent?

  4. Hi Steve. Am a newer reader,love your blog-Thank You for it! Perusing labels,was excited to see CITRONELLA ants! These must be the tiny,traslucent glowing babies I call 'aromatic ants',of ignorance. Usually I smell them before seeing I have disrupted a colony; my cats are very drawn to these creatures,like a catnip. I wonder if any native creatures find this scent alluring? One might guess the scent would repel intruders. Any ideas? Take care.

  5. I've also seen cats attracted to the Citronella ants. I don't know how the scent affects most animals, but I have seen both Opossums and Skunks digging up the colonies.