Nature Notes: The Colonists

    During a normal year, many different insects and arthropods enter and exit my room in Noyac. Very few stay for more than a day or two. Some pass away in the night and are found dead the next morning. As spring heats up, the number coming and going increases. Flying insects, crawling insects, sow bugs, millipedes, centipedes, crickets, spiders, and ants make up the bulk of the visitors. Spiders, in particular, daddy longlegs, will pay the longest visits, occupying the same spot for days, even weeks.
    When it rains, special visitors such as Argentine ants show up, apparently to stay dry. Last weekend was rainy and in less than a day, a horde of Argentine ants appeared. These little guys (some are all female workers) started arriving en masse late Friday afternoon. A few “scouts” were seen earlier during the wettish week, but never more than two or three at a time.
    On Friday they formed two lines, one crawling up the edge of the window frame and one crawling down it, presumably to the ground only five feet below. Argentine ants are among the smallest of insects, less than an eighth of an inch long and about a third of that wide and high. They are brown and can crawl through the tiniest of spaces to gain entry to the inside from outside.
    I counted the number crawling up as opposed to the number crawling down for several minutes. The up number was about one and a half times the down number. That could only mean one thing — they were accumulating on a shelf that juts out from the window frame crosspiece. Not only were they gathering there, but some of the up ants were carrying little white dots in their mandibles; the ones going back down were all empty-handed.
    “Ah,” I said to myself, “they are moving the eggs laid by their queens to high ground.” Since the ones with eggs were disappearing under my phone cradle while the empty-handed ones were coming out from under the cradle, I assumed that the cradle was becoming their new nest.
    On Saturday at noon, I was curious and lifted the phone cradle a few inches off the shelf only to find that the 3-inch-by-5-inch space under the cradle was completely filled with white eggs, each about a 64th of an inch in diameter.
    Now that I had discovered their secret, I wondered what they would do. Keep their nest where it was, or start carrying the eggs back down to another spot?
    In the next two hours, none of the ants going down were carrying eggs, so I assumed that the nest was safe where it was. I even put some orts of food out next to the cradle so that the worker ants had something to munch on in between trips to and fro.
    Saturday night I got a comeuppance. I took my laptop computer from the same shelf about a foot away from the phone cradle, booted it up and began playing solitaire. Within five minutes a few ants were seen scurrying across the screen and back and forth along the screen frame.
    I began whisking them off with a shaving brush but as the computer heated up, more and more appeared. They were streaming in and out of the computer from under the keyboard. “Oh,” I thought to myself, “they ran out of space under the phone cradle and some extras had moved into my computer.”
    After about an hour or so, I lifted up the laptop and there in my lap were hundreds of ant eggs and hundreds of ants. Perhaps, because I had disturbed them under the cradle during the day, they had decided to move some of the eggs to a safer place. The laptop innards offered them more security and more space. It was a grand hotel compared to the Motel 6 phone cradle.
    I whisked all of the eggs and ants to the floor. they would have to pick up for themselves and continued playing on the laptop hoping that all the ants and their eggs had left.
    I went to bed and Sunday noticed that the ants were busy crawling up and down the window frame to and from the phone cradle. This time the down ants were carrying the eggs, the up ants were empty-handed. Apparently, ants had had enough of my interfering ways. They were abandoning the shelf and phone cradle altogether and were moving lock, stock, and barrel to new quarters somewhere down below, maybe even back outside.
    I timed them as they moved coming and going along the same trail. The eggless ones were faster, moving at a clip of an inch per second, a foot in 12 seconds, five feet in a minute, in other words, .057 miles per hour. They looked like they were traveling fast on their six little legs, but in reality they were traveling about as fast as a box turtle and about 90 times slower than the speed at which an average person walks.
    They went as fast up and down as they did horizontally. The ones carrying the eggs took longer, one foot in a second and a half.
    The Argentine ant is now found throughout the world. It may be the most numerous and widespread of all invasive insects. Argentine ants form super colonies up and down the coasts of North America, Europe, and Asia, which turn out to be very closely genetically related. In other words ants from one super colony in Japan can easily be interchanged with ones from California. They don’t fight with each other. When they meet each other, they pause and touch heads for a split second before traveling on. They are earnest. They keep on trucking, and although their brains (ganglia) are smaller than a grain of sand, they seem to know what they are doing; they know their roles. They don’t waste time trying to figure themselves out.
    Perhaps­ that is why they displace other ant colonies composed of ants much larger than they are and much more aggressive. They just go about their business and are very successful at it. Do they laugh, cry, carry on, enjoy a good joke, and believe in a super-being as we humans? I suppose, not at all. But they take care of their own and don’t fight with each other. Will they outlive us? There’s a very good chance of that!
     And, oh, yes, during the typing of this column a few Argentine ants poked their heads out of the laptop and quickly went back in.


Comments



These insects are really traveling from and to seasonally. It will depend on what time of the year it is by far. That's how they live. And now that summer is coming up it is expected that these ants will place themselves to a place near from a source of food. They are like just having so many road trips during this season.