Ants

May 24, 2022

Melissa had started our outside workday without me on Saturday.  She began clearing the weeds and overgrowth from the front bed under the Japanese Maple and sat on the pavement beside the bed to make it easier to work.  It did not take too long for her to call out and ask me to come outside.  The accumulated weeds and leaves had hidden a colony of black ants.  When Melissa disturbed them, they swarmed and became aggressive trying to protect the colony and were biting her hands and legs.  When I arrived, I saw she had gotten into the ant nest.  While some were busy biting her, most were scurrying around trying to protect the egg sacks that had been exposed.  These appeared to be pavement ants.

When I looked online, I found pavement ants (Tetramorium caespitum) are about 1/8 inch (0.32 cam) long with a brown or black body.  Pavement ants are an introduced species of soil-nesting ant believed to have been transported to the US in the holds of European merchant ships during the 1700’s to 1800’s.  The ships were filled with soil to provide weight (ballast) on the overseas voyage.  Once they arrived in port, the soil (along with the uninvited ants) was removed and replaced with goods to carry back across the Atlantic.  Pavement ants are one of the most common species in the US and are not often viewed as a nuisance, unless they invade your outdoor picnic (or your succulent bed).  Pavement ants earned their name for their tendency to burrow under sidewalks, driveways, and building slabs.  The little dirt mounds are often seen piled on top of the pavement.  They are rarely aggressive but can both sting and bite.  They were kind enough to do both to Melissa.

There are several other species of black ants that bite.  While these bites may cause a small welt and itching, they are not dangerous.  Acrobat ants (Crematogaster spp.) are 1/16 to 1/8 inch (0.16 to 0.32 cm) long and may be black to light brown in color.  Nests are usually outdoors under stones, in the soil, or in old trees.  Their name comes from their ability to raise their abdomens over their heads.  Carpenter ants (Camponotus spp.) are about 1/4 to 1/2 inch (0.64 to 1.28 cm) long and can be black, red, brown, or yellow.  They are the largest black ant found in homes and are often mistaken for termites.  Nests are found in rotten wood, both indoors and out.  The black imported fire ant (Solenopsis richteri) is nearly identical to the red imported fire ant (Solenopsis invicta).  Both are small ants, about 1/8 inch (0.32 cm) long, but the black fire ant is dark brown or black in color as opposed to reddish brown.  Black fire ants are the exception and may require medical treatment since some people are allergic to their venom.   Fire ants attack by biting their prey and injecting venom with a stinger.  The venom causes an intense burning sensation and creates a white pustule at the bite site.

𝗧HOUGHTS:  I never paid much attention to the ants in our yard when I was a boy, other than knowing not to mess with their nests.  That changed when I participated in an archeological survey in college.  We were retroactively surveying a reservoir that had been built several decades earlier.  The vegetation and grass were well established, and we needed to “shovel test” the grounds to see if there were any sign of human activity (chert flakes, etc.).  Of the 1000’s of shovels full of dirt unearthed, it was rare to not impact an ant colony.  There are 12,762 known species of ants and the estimated total of ant species is more than 22,000.  It is estimated the over 10 quadrillion ants on the planet comprise from 15% to 25% of the animal biomass and the estimated total weight is equal that of all humans.  Ants inhabit every continent on earth except Antarctica and a few islands.  Ants are successful because of their ability to organize and communicate with each other.  During the 1950’s ants were the protagonists of several horror B-movies.  Perhaps this was more predictive than we thought.  Act for all. Change is coming and it starts with you.