15. Periodical Cicada Invasions
Cicadas are periodical insects that gestate underground and only emerge in periods of every 13 to 17 years. They tend to live most of their lives underground, from the time that they hatch, and appear only to mate. The eggs are then buried underground, and the life cycle begins once again. This is why they arise only once every 13 to 17 years, depending on the species. When they do emerge, they can create massive infestations that can disrupt local economies, depending on how severe the swarms become. That said, there are plenty of cicada fans who wait patiently for the next encounter.
In the United States, cicadas are most common on the East Coast and the Midwest. When they emerge, billions of the bugs swarm towns and cities. When they die, especially en masse, they emit a foul odor that can become nauseating. That is what happened in the summer of 2013, when a cicada cycle brought billions of the bugs to the East Coast, infesting areas from Washington, DC to New York City. Cicada fans took the rare opportunity to observe them first hand, while most people found them to be a nuisance at best. Due to climate change, their cycles may begin to change unpredictably.
There are also annual cicadas that appear each summer in warmer parts of the central and Eastern United States. Whether you think their song is a beauty of summer or a nuisance, cicadas are here to stay at least every year, and some years… watch out for the swarm!