Bugs of Beaver Creek: Ants

Ant

I use the term “bugs” in the title to encompass all insects, arachnids, and other non-insect arthropods. Bugs pollinate our plants, mix and aerate our soil, dispose of carrion and dung, feed on pests and provide food for other life forms. In return, many of us fear them, swat or squish them, spray them with poisons, or at best ignore them. It must be said that we depend upon bugs far more than they depend on us. Indeed, if they were to suddenly disappear it is doubtful whether the human species would be able to survive as we do, if at all.

There is a group of insects that has colonized almost every terrestrial habitat on the planet, and consequently there are a lot of them here at Beaver Creek. They were the first insect I sighted this spring and are fascinating animals if you take a closer look:

Ants

Ants are of the scientific order Hymenoptera, along with bees and wasps, and are believed to be descendent from the latter, having lost permanent wings and evolving large, highly organized societies.

Ant colonies are structured into castes, with egg-laying queens being central to the production of drones and workers.

If you disturb an ant’s nest while digging, you may notice amidst the soil small white capsules which the workers will frantically grab in their mandibles to carry to safety. These are the eggs. Workers protect the colony’s eggs from harm and meticulously clean them of parasites.

Most individuals in an ant colony are sterile females, but males are produced periodically for mating. Winged males can sometimes be observed leaving a colony with winged females to mate and help start a new colony elsewhere. After mating, the males will die and the females will shed their wings to begin life as reproductive queens.

Ants communicate through scented chemicals called pheromones. This method of communication is extremely effective, allowing workers to quickly alert the colony to danger or lead them to food. Despite their small size ants are very strong and, by working as a collective, ants can overpower relatively large prey. A swarm of ants may bite at the leg joints or other vulnerable areas of their target then irritate the wounds with a spray of formic acid from their abdomens (formica means “ant” in Latin).

Other species of ants are herbivores and may even be skilled farmers, growing fungus on carpets of leaves like the Leafcutter ants of the tropics, or herding and “milking” aphids for sugar-rich honeydew.

Because of their efficient organization, ants can sustain large colonies comprised of millions of individuals. Sometimes ant colonies are talked about as a single unified entity, called a superorganism.

With so many ants crawling about, digging out tunnels and chambers in the earth, they have been recognized as the premier turners of soil. The fertility of our fields would decrease dramatically without the aid of ants.

Of the approximately 8,800 known species of ant, I have currently identified four in our co-op, and there are undoubtedly more to be discovered.

The Pavement Ant (Tetramorium caespitum) commonly nests in cracks in pavement and concrete. I have watched these small black ants outdoors, zig-zagging a path from the rear of our unit to our composter, transporting materials back to the colony.

Upon overturning a stepping stone, I discovered a nest of Tetramorium bicarinatum, similar in size to the Pavement Ant (3-4 mm) but with a deep red head and thorax and dark abdomen. A day later I lifted the same stone to find a second nest of the species Acanthomyops claviger, sometimes called citronella ants due to the potent lemony scent they release when disturbed. These small bright yellow ants were not happy that I had uncovered their nest, and seemed less happy when the adjacent colony of reddish ants began attacking their yellow workers. An epic battle of miniscule proportions ensued.

The fourth ant species I have identified is the Black Carpenter Ant (Camponotus pennsylvanicus), a common and comparatively large ant. It gets its name from its practice of excavating nests in wood, though it does not eat the wood as is sometimes thought.

I have also recently found a tiny brown ant’s nest in our unit’s backyard, which I have not conclusively identified (unsurprisingly, “tiny” and “brown” are not characteristics unique to one species).

In the Amazon rainforest, nearly one third of the total animal biomass consists of ants. The ratio is similar in many other land environments. Whether you are walking along the sidewalk, digging in your garden plot, or even cooking in your kitchen, there is a good chance that an ant is nearby. It has been estimated that for every one of us there are one million ants.

Next time you see an ant, despite how small and insignificant it may seem, remember that they are highly evolved, complex animals that have vital ties to the web of life. And they have you outnumbered.