Did that stick just move? Your eyes may not be not tricking you! You may have been lucky enough to see a walking stick insect.
More than 3,000 different kinds of walking sticks live in the world. Illinois has five species of these insects. The one most often seen is Diapheromera femorata, the common walking stick.
In the 1800s, walking sticks covered the trees in such large numbers they were considered a pest. They would eat so many leaves the trees would be bare. Today their populations are down to manageable numbers. It can actually be a little hard to find one, but not impossible if you know what to look for.
Journey as an Egg
In nature, females usually need to find a mate to have successful eggs. However, if a female walking stick can’t find a male during mating season she just lays her own eggs. All these eggs will watch as female walking sticks.
A walking stick’s eggs drop from the tree canopy down to the soil. They are covered in a hard shell called a capitulum. This shell is a delicious treat for ants. The ants bring the egg home to eat the outside shell and then toss what if left into their garbage area. What is left contains the walking stick egg, which can safely finish developing. A few months later, a baby walking stick will emerge and make its way out of the ant home.
Molting to Grow Strong
Young walking sticks are called nymphs. When they hatch, they are not even a centimeter long. They are greenish-yellow in color, so they blend right in with shrubs. To grow, they molt, or shed, their skin, getting bigger each time. If a young walking stick loses a leg to a predator, it is able to regrow the leg during the molting process.
While they are young, they start changing to a darker brown color and climbing to the tree tops. By August, they will be full adults, measuring 3 inches to 4 inches long.
Adaptations for Survival
Walking sticks have a few ways to hide from predators like birds, reptiles and spiders. First, they are active at night, so they can use darkness as a cover. Plus, their camouflage makes them look like a brown stick, which is perfect because they live and feed in the trees.
On a windy day, walking sticks will sway with the wind to blend in with the rest of the tree’s movements. If a predator does spot a walking stick, it can move its front legs and antennas straight out to make it appear to be a skinny stick. If this still doesn’t fool the predator, the walking stick will tense up to be as stiff as a board, which makes it feel like a stick.
One kind of predator is not that easily fooled by these tricks. Bats are able to use their echolocation to find exactly where the walking stick is hiding.
Are you up for the challenge of finding a common walking stick? The first step is to find an area with lots of trees. Walking sticks especially like areas where oak trees grow.
Hike around the area, checking the bark and branches. Do you have oak trees in your own back yard? Ask an adult if you can climb the trees to get a closer look! Keep an eye out for chewed leaves. This may be a sign a walking stick is close by. Make sure to check every stick. Some may crawl away!