Poisonous caterpillars are found all across the world and are poisonous to both predators and people. In fact, most of the time these creatures gain their poisons from plants. Many appear to be very beautiful, but behind that beautiful façade is lurking a very painful sting or an even worse poison. Some cause mere discomfort of the skin, but others can be deadly. One fine example of a poisonous type of caterpillar is the wooly bear caterpillar.
The wooly bear caterpillar is not the most poisonous of the caterpillars, but it can provide an irritation of the skin. Being the larvae of the Isabella tiger moth, the caterpillar has very long and thick fur that is mainly black with an almost coppery-like band in its middle. It may also may appear yellow to an almost dull orange in its adult larvae stage with a tiny head and fur covered thorax. Quite often the larvae is up and about even during the winter, though few people are aware of this. When the weather begins to warm, the caterpillar is munching on weeds and grass, preparing for the winter ahead.
As one of the types of poisonous caterpillars, this caterpillar really is not poisonous per se, but eats certain plants to help it deal with varied parasites that it gets, using the nectar of the plants to poison the parasites and rid itself of them. Unfortunately, though the poison from the plants is not harmful to the caterpillar, it is a problem for people and animals.
The caterpillar eats more and more as it gets to it adult larvae stage, warding off more and more parasites. Its black appearance decreases and its copper band grows from one end of its body to the other. Quite often these caterpillars will avoid human contact by playing dead. They cannot inject any venom, do not cause swelling, inflammation, injuries or irritations, but when disturbed, picked up and handled, their bristly fur still carries considerable remnants of the poisonous plants that they came into to contact with. Unfortunately, the poison is an irritant, causing potential dermatitis in some people, especially those with very sensitive skin types.
Quite often you can find poisonous caterpillars right in your backyard. The wooly bear caterpillar is a more frequent visitor in most yards, especially in gardens containing forbs and herbs. So, it is important if you grow these plants to be very cautious when coming in contact with this caterpillar or any caterpillar with brilliant or bright colours because the chances are that they are carrying a toxin that might make you sick!
Photo: wooly bear caterpillar – public domain photo, http://upload.wikimedia.org/wikipedia/commons/7/71/Woolly-Bear-Caterpillar.jpg