Saturday, December 19, 2009

Stick Insects

The following article was published in the Fairfield Glade Sun newspaper November 25, 2009.

Enjoying Nature


Don Hazel


When is a stick not a stick?

If you look at the picture it doesn’t look like much. If anything it just looks like a piece of a twig or a stick…and the stick likes it that way.


What you are looking at in the photo is an insect called an American walking stick, or sometimes just called a stick insect. The walking stick uses its unique shape to hide from predators.


For some reason, this is the time of year when I usually see the most walking sticks. It may be because they grow all summer through a series of molts, or shedding of their skin and they may just be bigger this time of year and easier to spot. But they are by no means easy to spot unless one happens to be on the side of your house or on your driveway like this one was.


A fellow hiker spotted a walking stick a couple of weeks ago. Actually she spotted two that were mating. One was a fat female 4 or 5 inches long and the other was a male only about one fourth her size. But as crazy as it may seem, the female didn’t need the male to raise a family.


Walking sticks are a rare type of animal that can lay fertile eggs without the need for a male. This process is called parthenogenetic reproduction. However, without male fertilization the young will all be females. Males are only needed to fertilize the female in order to produce some percentage of males. It is certainly good thing that this idea didn’t catch on in human society. The world could be all females with no need for males. That is a sobering and scary thought…on many levels…for both men and women.


For the most part walking sticks are pretty harmless. But supposedly they can spray a defensive chemical that can cause temporary blindness and pain. I have handled walking sticks and never run into this issue, but I wouldn’t get one too close to my eyes. They do have chewing mandibles and could cause a pinch but not really a bite. The biggest danger is imported foreign walking sticks that are sold in the pet trade. In some places like California these non-native walking sticks have escaped and become a plant eating, sidewalk covering, nuisance.


Walking sticks eat leaves, primarily oak leaves and you know we have plenty of those around here. I know that some of you obsessed leave rakers and baggers out there wish that walking sticks ate a few more oak leaves. They usually cause no serious damage to trees unless there is an unusually large population. Birds, primarily crows and robins, seem to like to eat walking sticks.


So if that stick on your driveway seems to be slowing moving, look closely, it may be a stick that is not really a stick. It may be a walking stick.


Comments, questions or suggestions for future nature articles are welcome at don.hazel@gmail.com

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