An insect invasion has begun in the United States. Experts even speak of one Cicada apocalypse
. This is because two broods coincide, which last appeared at the beginning of the 19th century and only appeared together again in the middle of the 23rd century (via CNNEspanol).
In the rare event, parts of the USA are hit by particularly large swarms of cicadas.
- A brood of cicadas emerges from the ground and appears every 13 years.
- In addition, there is a brood that follows a rhythm of 17 years.
- Experts expect up to a trillion cicadas from May to June.
These two broods (broods XIII and XIX) were last in 1803, exactly 221 years ago, met. And it probably won’t happen again until 2245.
There could be a clash in Illinois
Im Detail: There are around 3,000 species of cicadas worldwide. They spend most of their lives underground as larvae before crawling to the surface as adults to reproduce.
The rhythm at which the cicadas reach the surface of the earth varies considerably. There are species that have a cycle of two to five years, others only come to light every 13 or even every 17 years.
Brood XIX (17-year cycle) has now begun to emerge in the US states of North Carolina and South Carolina (on the east coast of the United States). Brood XIII (13-year cycle) is also expected shortly.
The areas where they reach the surface of the earth are different, as brood XIII hatches in the Midwest of the USA. But in the state of Illinois (via ZDF) there could be overlap as the insects move across the country in search of food and mates.
Almost as loud as an airplane turbine
The cicadas of the genus Magicicada
are relatively large. Adults measure between 20 and 33 millimeters. They have large, black bodies and red eyes. They feed on plant juices. However, they are completely harmless to humans. The same applies to pets.
Cicadas can be recognized by their characteristic chirping (Here is the example of a cicada in a YouTube video).
This can be very loud when there are large gatherings of insects: various sources speak of this 84 bis 110 decibels. This is in the range of an aircraft turbine (at a distance of ten meters). In the range that humans can hear, only the males make sounds.
The sounds are used by male cicadas to attract females. After mating they die. The females live a little longer until they lay their eggs. In total, hatched cicadas only live for about four to six weeks.
The songs of the cicadas are also species-specific and are used to distinguish between the different species, as they often differ little or not at all.