|A Periodical Cicada perched|
Indeed, we are in the midst of an emergence of Periodical Cicadas, but not the natural phenomenon of a great cicada year. The Big One is not due until 2021. Cicadas are insects known for the loud songs of the males. While we have numerous species of annual cicadas that come out every year during summer (many of which take more than one year to mature, but they're staggered in breeding so some are out every year), Periodical Cicada are much different.
Periodical Cicadas (Magicicada species) emerge in huge numbers in late spring, generally on 13 and 17 year cycles. There are 7 Magicicada species, of which 3 are local to the DC area. They generally time themselves so they come out in gigantic numbers, thus the reference to biblical plagues of locust and their alternate name. By all coming out (and earlier in the season before predators like Cicada Killer wasps are active) at one time in such huge numbers, they make it impossible for all of them to be eaten. Though a favorite food, they just are too many to all get eaten. Since they come out after such an extended period of years underground, no single predator has adapted to feed on them exclusively. They just overwhelm all the potential hazards, so though thousands die, millions make it.
Since their emergence is synchronized over different regions, people have divided these regional cycles into Broods. There were 23 different Broods recognized at one time, but some have gone extinct. The DC area is part of Brood X.
Periodical Cicadas spend the vast majority of their lives underground, usually either 13 or 17 years. The larvae feed for years on the roots of trees for the most part, sucking what they need to survive from them, molting into bigger larvae every year. Though that many feeding would seem to damage the trees, they rarely cause any real damage in this stage. Eventually their internal clocks go off, usually after the ground 8 inches down reaches 64 degrees Fahrenheit. Sunnier areas thus have them emerge before shadier ones.
The larvae (referred to as nymphs) somehow time their climb out of their burrows for the same year (mostly). Some get to the surface before others, but many may just wait until the rest are ready and stay underground, though their burrow entrances of pushed up soil, called turrets, may become noticeable.
|Exit holes and a shed skin|
Those that are ready to emerge often wait until just after dark and then climb the nearest thing around them. This is usually a tree, but tall plants and even walls are fair game. They often have better success obviously on less slick surfaces such as rough barked trees. The nymphs climb until they get some altitude and find a good place they can grasp firmly. They then undergo the final molting of their exoskeletons of their lives.
|A cicada partially exiting its old skin|
|A cicada starts to spread its wings and dry off as it is close to completing its final molt|
|The damage caused by the cicada inserting its eggs into a twig.|
The speeding up of development is called acceleration. It is often connected to weather and climatic changes. So for example, multiple hot and cold weather patterns may trick some into thinking it's passed multiple years and come out early. This is what may be happening locally now. Regardless why, we are having an early emergence in some local populations throughout the DC area.
So it may seem as though we have tons out now, but they're a very small percentage of the overall brood. Wait until we see the true appearance of Brood X in 2021! Sometimes when enough periodical cicadas emerge earlier (and plus or minus 4 years seems to be the most commonly occurring stragglers), it is believed that new broods may start. But it would take quite a few to emerge and then somehow survive so many years to start a new brood, at least in theory.
No matter how many emerge, Periodical Cicadas are a favorite food of just about anything. You'll see birds gorging themselves on them, and this may well lead to many more nestling survivors in these times of plenty. Squirrels and other animals that normally don't regularly eat insects may now be seen stuffing themselves and their young with this fantastic food supply. I've even seen copperhead snakes feast on them.
|Eating a 17 Year Locust back in 2004|