Nature Notebook – Walking Sticks
There is a population explosion at the nature center! Look carefully at the photo. There are about 20 walking stick insects (in the nymph stage) sitting on the terrarium glass. A few adults (brown) and many more nymphs (green) also inhabit the cage. The nymphs will mature in about three months.
Female stick insects can produce unfertilized eggs that can hatch and grow into new females. The process is parthenogenesis. When you have well cared for captives, you end up with a lot of walking sticks.
The wild populations can also have population spikes but the numerous predators usually bring them back into check. To avoid being eaten, walking sticks are masters at camouflage. Their long, thin bodies and legs resemble twigs and their swaying walk simulates a twig moving in a breeze. If hiding doesn’t work, some walking sticks resort to chemical warfare. A walking stick may just fall from its tree and lie still in the leaf litter where it becomes nearly invisible.
As a last resort, the insect can run from attack, leaving a leg in the predator’s mouth. Walking sticks are the only insects known to regenerate lost limbs.