Life Cycle of the Woolly Bear Caterpillar

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The Woolly Bear Caterpillar is the lava of the Isabella Tiger moth its Latin name (Pyrrhactia Isabella) other common names for this caterpillar are Fuzzy Bear and the Hedgehog Caterpillar. 

The home range of the Woolly Bear Caterpillar is Northern Mexico to southern Canada, but it can also be found as far North in the Arctic, but because of the shortness of the summer seasons in these regions these caterpillars can stay up to fourteen years in this state before consuming enough food to be able to form the chrysalis and transforming into a moth.

The eggs hatch when the weather warms up and they start to eat.  The caterpillars eat grass and leaves. 

The caterpillar has black ends and a reddish-brown middle and is covered in bristles called setae. These bristles can be an irritant to some people when holding the caterpillar.  The body is made up of thirteen segments.  During their caterpillar stage they can moult up to six times and each time they moult the mid reddish-brown section decreases changing into a black section.  The caterpillar has very limited and poor sight.

 When the Woolly Bear caterpillar has consumed enough food and is ready to change into a moth it will form a chrysalis over his body and stay there for three to four weeks before emerging as a moth and completing the life cycle.

There is an old wives tale that says that these caterpillars can tell the weather for the forth coming winter by the number of the reddish bands in the middle.  It is thought that it is more likely that these bands represent the wealth of the summer season just past. 

One special trait of the Woolley Bear Caterpillar is that if it hasn’t consumed enough food in the course of the year it can hibernate until the following spring, the caterpillar finds somewhere quite to go, under a rock or in amongst some leaves.  When the ground freezes  so does the caterpillar, it can withstand temperatures as low as minus 6 – minus 8 degrees, even the heart stops beating, it produces an organic anti freeze and in the spring it just wakes up and starts eating again, until it is ready to form a chrysalis and continue the life cycle.

The moth is a very beautiful Isabella Tiger Moth apart from its sticking appearance it has another unique talent in that it can make a sound, an ability that other insects lack.  

More about this author: Sharon Rowe

From Around the Web

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