Ants Collecting Feathers: More of the Story Revealed

Back in 2015, we asked why ants collect feathers. We suggested food, moisture, or that feathers are left behind by anting birds.

Photograph by (Bob) Ricardo Solar at Flickr, shared under Attribution-NonCommercial-ShareAlike 2.0 Generic (CC BY-NC-SA 2.0)

Now a recent article in Scientific American has another answer. Brazilian scientist Inácio Gomes, of the Federal University of Viçosa,  suggests Pheidole oxyops surround their nests with feathers to lure other insects to the area, where they fall in. Thus, the decorated ant nests serve as pitfall traps.

Gomes discounted the moisture idea by adding wet cotton balls. The added source of water apparently did not change the ants’ behavior.

This is cool, but since ants also drag the feathers into  the nest, it is likely there is still more to learn.

The original study was published in Ecological Entomology in Feb. 2019.

An Ant World View – Tiny Flowers

If you live in the North, you might be wishing for an ant sighting about now. The grass is brown and the trees have shed their leaves.

Well, maybe not all the trees. When I went out for a walk I noticed the African sumac, Rhus lancea, has a spread of yellow-green material beneath it. Is it pollen?

I had to check it out, of course.

The tree is flowering.

It isn’t pollen on the ground. Instead, it is a layer of dropped flowers.

What’s that bright cluster?

There’s another.

And another, each with an entrance hole in the center. There are eight or nine bright green clumps in all.

It seemed likely they are ant nests.

Can you spot it? Yes, an ant!

They look like Tetramorium or pavement ants.

 

One by one the workers carry a flower into the nest entrance and disappear.

 

The pavement ants are apparently taking advantage of a local abundance during the slow winter months. (The ant is blurry, but I thought the pollen on its head was cool.)

Seeing some ants at work in January? That is an unexpected bounty for me.

Have you ever seen Tetramorium gather flowers or other plant material?

Allegheny Mound Ants, Formica exsectoides

On a recent trip to western New York State, we made a cool discovery.

Driving along a quiet country road, we came upon some huge ant mounds.

It’s hard to tell how big they were until someone plays spokesmodel.

We found not just one mound, not just two mounds,

but more than twenty of them.

In the photo the size is a bit deceptive because the mounds were up on a bank along the road. However, they were still relatively massive. Most of them were at least two feet tall.

These impressive structures were the nests of the Allegheny mound ant, Formica exsectoides.

Each of the mounds was covered with many active ants. According to the literature, the colonies have multiple queens and split up via fission to form clumps of interconnected mounds.

The mounds are thought to help the ants regulate the temperature inside the nest, which in turn optimizes the development of the young.

Doing some comparisons, it looked like the top of each mound was clear of vegetation and the upper surface was relatively uniform.

This photograph shows a closer view of some ants working on top of the mound.

Lower down, the mound was covered with sparse vegetation and riddled with holes like a sponge. It would be fascinating to know whether these were for drainage, air circulation, or what.

Checking out the lower holes, we found they did serve as entrances and exits. One contained a myrmecophile, although it moved away so fast I couldn’t tell if it was a beetle or roach nymph.

The ants were very active. It didn’t take long to find a nearby foraging trail.


(This was filmed using a small endoscope attached to laptop, which required two people to run. I need to figure out a way to mount it on some sort of mobile tripod. Any suggestions?)

Compared to a similar-sized foraging trail of our Arizona Pogonomyrmex harvester ants, it was noticeable that these ants weren’t carrying anything. Because they are known to feed on insects, as well as gather honeydew, they must process their food in the field. Anyone know more about their foraging behavior?

Even to people who aren’t interested in ants, these mounds were such a presence that they inspired awe and curiosity. It would be great to get a chance to study them longer.

Have you ever encountered Allegheny mount ant nests?