There are several species of cicadas that live in the United States. The ones in the south come out every 13 years. The ones that are soon to emerge come out every 17 years. The amount of years they take to come out of the underground is based on their life cycle. Some live to about 13 years and others up to 17. For those years they stay underground to live and feed on nutrients that are below our soil. When the ones that are about to come out do so, they will overpopulate humans 600 to 1. These bugs are to merge from areas such as Maryland and New Jersey any day now. Some of these bugs have already been spotted. They are going to spread throughout the east coast, but there is nothing to fear. The only disturbance they may cause is the noise amplified by billions of them.