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.

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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.

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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.

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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.

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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.

Photo of the Week – December 10, 2015

Earlier this week, I mentioned the hike I took at the Niobrara Valley Preserve Monday afternoon and evening.  I carried my camera on the walk but waited in vain for decent photography light.  The heavy clouds started to thin as sunset time neared, but the sun dropped below the horizon before ever popping through.  However, a short time later, as the clouds continued to thin, they suddenly lit up with beautiful pink and purple color.

Tree skeletons in post sunset glow in the 2012 wildfire area at TNC's Niobrara Valley Preserve, Nebraska.

This tree apparently supported a fallen tree or branch for quite a few years – long enough to have molded itself around it.

Tree skeletons in post sunset glow in the 2012 wildfire area at TNC's Niobrara Valley Preserve, Nebraska.

Tree silhouettes against the post-sunset sky.

Not long after the color faded from the sky, the first stars started to appear and the clouds continued to disperse.  By the time I reached the car, most of the sky was clear and the stars were strikingly bright in the sky.  It was only about 7:30 pm, so I decided to extend my hike a little and found a few trees to put in front of the stars.

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Starry sky along the Niobrara River.  This pine tree is the same one I featured a few posts ago as I compared three years of photos showing fire recovery.

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At the time, I thought the glow on the horizon was the nearby town of Valentine, but now I wonder if it was actually the very last of the glow from the sun.

Listening to coyotes and great horned owls while admiring more stars than anyone could count in a lifetime of lifetimes was a pretty great way to end the day.