Don’t worry, Long Island broods are between cycles
You may have heard about the rare insect event that is happening in parts of the central U.S.: two broods of periodic cicadas are emerging simultaneously. Brood XIII and brood XIX, each on a 17-year and 13-year cycle respectively, will leave the soil to molt and then mate. There may be up to a trillion of these insects leaving their chitinous exoskeletons behind to adorn any and all available surfaces. The adults will then find a perch and begin their droning call.
Periodical cicadas (Magicicada) are found only in eastern North America. There are seven species — four with 13-year life cycles and three with 17-year cycles. The three 17-year species are generally northern in distribution, while the 13-year species are generally southern and midwestern. Magicicada are so synchronized developmentally that they are nearly absent as adults in the 12 or 16 years between emergences. When they do emerge after their long juvenile periods, they do so in huge numbers, forming much denser aggregations than those achieved by most other cicadas.
2024 is a special year for periodical cicadas because it is the first time since 2015 a 13-year brood will emerge in the same year as a 17-year brood, the first time since 1998 adjacent 13-and 17-year broods will emerge in the same year and the first time since 1803 Brood XIX and XIII will co-emerge. You will also be able to see all seven named periodical cicada species as adults in the same year, which will not happen again until 2037.
Periodical cicadas should not be confused with annual (dog day) cicadas, which are larger, usually green with black eyes, and appear every summer in much smaller numbers. There are 150 or so species of cicada in the U.S. Only the seven Magicicada species have synchronized development and periodical emergences. The rest of the species, the so-called annual cicadas, have unsynchronized development, so some individuals mature in every year and can be heard every summer.
Adult periodical cicadas usually have red eyes (occasionally white, or rarely blue or marbled white and orange). Their dark bodies measure just over 1½ inches long.
Adults live for about 4 to 6 weeks during which their sole purpose is to mate and lay eggs. Males are responsible for the familiar droning, which is how they call for mates. Cicada “songs” are heard from early morning to late evening as long as adults are present.
The branch damage, or “flagging,” associated with periodical cicadas results from females laying eggs in small twigs. A female cuts two parallel slits in a twig where she lays 24 to 28 eggs. Each female can lay over 600 eggs on multiple branches. Sometimes a continuous slit 2 to 3 inches long is formed as she slowly makes her way up a twig. The slits can cause breakage, or flagging, of the tips of the branches.
The eggs hatch in 6 weeks, and young cicadas, or nymphs, fall to the ground where they burrow into the soil and spend the next 17 years feeding on small roots, without causing significant damage. At the end of this time, usually in May and early June, nymphs crawl out of the soil and climb up tree trunks or other vertical objects where they shed their skins and emerge as adults.
Cicadas are a bountiful meal for a number of predators, including fish, turkeys, squirrels, birds, reptiles, amphibians, insects and arachnids. Of particular interest is the eastern cicada killer, a two-inch wasp that stings the cicada to paralyze it before carrying its prey back to an underground burrow. It lays an egg on the insect and then buries the bundle. Female eggs are given two or three cicada meals, male eggs a single insect. This wasp feeds on the annual cicada.
Although the immense number of cicadas can be a bit overwhelming, they are not hazardous to people or pets and they do not bite or sting.
Cicadas have excellent vision. Cicadas have five eyes (two large red compound eyes on the sides of the head, and three small ocelli (simple eyes) located in a triangle on the front of the head). Periodical cicadas simply don’t much care what they land on, since in natural circumstances everything they land on is a tree; don’t take it personally when periodical cicadas land on your head/pet/car etc. Even the nymphs can see when they emerge from their burrows to metamorphose – they can head towards a tree– anything vertical – in the near-darkness from many meters away.
People do eat annual cicadas. It’s recommended that you panfry or parboil and then finish them off in the oven. Do not consume cicadas if you are allergic to shellfish.
—Information compiled by
Amanda Olsen
