Hubbard Fellowship Blog: Ant Swarm (and Lunch)

This post was written by Evan Barrientos, one of our Hubbard Fellows.  Evan is a talented writer and photographer and I encourage you to check out his personal blog. If you would like to see more of his photographs, you can follow him on Facebook.

Don’t worry, I didn’t eat a swarm of ants. But late last September while I was harvesting seeds I did notice enormous clouds of small flying insects swarming above the prairie. The swarms were constantly shifting shape but they were roughly the size of small cars slowly floating across the land. Intrigued, and slightly mesmerized, I walked directly beneath one.


Closer up I could see that the mystery insects had very narrow waists, which suggested that they might be in the order Hymenoptera (ants, bees, and wasps). Their brown color made me think they might be flying ants.


Then I began to notice several individuals crawling in the grass below the swarm. Some were caught in spider silk; not complete webs, but loose strands of silk. Looking around, I realized that there were dozens of silk strands scattered among the grasstops of the prairie. As I knelt to photograph one ensnared ant, I saw a small jumping spider stalking another. The spider crept up, grabbed the ant, and carried him away for lunch. Were these silk strands deliberate traps set by the jumping spiders or were they just remnants of ballooning juvenile spiders that happened to catch the ants? I still don’t know.


Later, I sent the photo below to James Trager, an ant expert, and learned that these were in fact flying ants, Myrmica americana to be specific. It still AMAZES me that there are people who can identify insect species  from just one photo!  He explained that there are actually three different species that currently are all called M. americana because two have not been officially named yet. The unnamed species I encountered is very common, which shows how much we still have to learn about even the insects in our backyards.


Not only did Trager know the species’ name, but also the explanation for their hypnotic swarming behavior. When it’s time for M. americana to reproduce,  winged males swarm together, forming what’s called a lek.  Reproductive females are drawn to the spectacle and watch from the leaves below. Males will periodically descend from the swarm to crawl around in search of females to mate with (or get snagged by spiders). If a male is lucky enough to avoid the predators below, he may find a female to copulate with. But the challenge doesn’t end there. Once a male begins copulating, dozens of other males will often swoop in and try to do the same, forming what’s called a “mating ball.” After the whole fiesta has ended, the female pulls out her wings (so that she can convert her wing muscle into food to feed her offspring via glandular secretions) and walks away in search of a place to start her own colony.

Finally, here’s a video of the lek, first at full speed, then in half-speed slow motion.

Field Day Reminder – TOMORROW, Rain or Shine! Also, A Bee Photo

A reminder – we will have our Platte River Prairies Field Day tomorrow, August 27, from 9am to 3:30.  Details can be found here.

Rain is in the forecast for tomorrow, but it looks like the best chances for precipitation are before and after the Field Day.  Either way, we’ll be there and will have plenty of things to see, do, and discuss, so please plan to attend.  (However, in addition to your lunch, you might throw in a rain jacket and/or umbrella just in case.)

Now that we’ve got that out of the way, here’s something completely unrelated:

As I was walking across my yard on the way home from work last night, I saw the following happening RIGHT IN THE MIDDLE OF MY SIDEWALK.

Two bumblebees (Bombus impatiens) trying to ensure the next generation of bumblebees.

Two bumblebees (Bombus impatiens) trying to ensure the next generation of bumblebees.

Three things.  First, this is a good way to see the sexual dimorphism of bumblebees.  (Don’t get excited – it just means that males and females are different sizes.)  Second, the stinger on the female looks like it’s in an awkward place.  Finally, the process of making new bumblebees apparently takes a while and the full attention of both parties.  I had time to go back to the truck, grab my camera gear, set up a couple flashes, and take quite a few photos.  After I got my photos, I put my gear away and walked by again and they were still going.

During the whole photography process, the bees completely ignored me, my gear, and the repeated firing of two flash units.  It seems like the bees would be pretty easy quarry for predators at times like this.  Maybe, instead of doing it in the middle of a sidewalk, it’d be a good idea to retreat to somewhere more sheltered?  (Get a room!)

Ok, everyone move along now.  Nothing more to see here.