Crawlies with Cri: by Christy Solo

Top to bottom, left to right: Ant tending their aphid livestock; glossy lady beetle with an aphid meal; jumping spider at the aphid buffet; and green lacewing larvae taking down an aphid. (Photo by Christy Solo, Illinois Valley News)

One thing we’ve learned in our Crawlies journey together is that every carnivorous or omnivorous critter loves to dine on a nice juicy aphid.
Aphids are like the Gummy Bears of the arthropod and bird world. In fact, an aphid by any other name would taste as sweet; they exude honeydew so “Gummy Bears” isn’t hyperbole.
So, how is it there is always an endless supply of aphids when they are clearly nature’s favorite snack food?
Aphids are clever girls.
Yes, nearly all aphids are female; this time of year 100% are.
So how do aphids keep making more aphids?
They’ve dispensed with the whole mating to reproduce thing, which is why there are few to no males.
Aphids give live birth to their own clones, up to 12 per day. This may seem exhausting, but it’s more efficient than expending energy to find a mate, mate, lay eggs and watch over eggs.
Each cloned female is born already chock full of eggs and ready to give birth to her own clones once she and the eggs have matured enough, which takes only a few days.
The development of unfertilized eggs is called parthenogenesis.
In colder climates a few males will be born in the fall to mate with females so the ladies can lay fertilized eggs which will overwinter as the adult females likely won’t survive freezing temperatures.
The following spring, clone females will hatch from the eggs, already filled with clone eggs and the colony is off and running.
In warmer climates, with no fear of winter’s chill, there may never be any males at all.
If aphids can reproduce so quickly and individually, how is the world not overrun by aphids?
Because they are clever girls.
Over producing new aphids would work against the aphids’ own best interest. They restrict their population growth so as not to overrun their food plant.
But wait, there’s more!
If any given clone colony (clonoly?) gets close to overpopulation, a new female form will be born – a generation of winged female clones.
The winged ladies will leave the colony and search out new, available food plants. When they’ve found a suitable home, they’ll settle in and almost immediately give birth to wingless clones to begin the new colony.
Having winged clones who fly off to start anew also ensures the clone will live on even if one colony is eradicated by hungry predators. A single songbird could easily wipe out a clone colony in no time at all.
There’s another fascinating way an aphid colony may move if their host plant starts to be over-eaten and begins to weaken (a dead host plant will signal the end of a colony).
Several species of ants have a symbiotic relationship with aphids. The ants harvest the honeydew the aphids excrete and in return the ant army protects the aphids from would-be predators.
The ants also protect the host plant. If the plant’s leaves show signs of wilting (which generally means the aphids are over-feeding) the ants will move the entire aphid colony one at a time to a new, healthy host plant.
Ants often must move their own colonies and those ladies excel at using their very sharp and bitey mandibles with gentleness to carry their own fragile eggs and larvae. So moving soft-bodied aphids without harming them is a natural task.
While aphids can cause damage to the health of plants, as we’ve learned it’s not in their best interest to do so. Eradicating aphids for the health of plants usually isn’t necessary. Signs of aphid over-eating are twisted and curled leaves, yellowed leaves, stunted or dead shoots and poor plant growth.
If your plants remain healthy, leave the aphids as they are a prime source of food for many beneficial insects as well as birds.