Swathed in blue and green, swarms of visitors are expected to grace Chicago with their presence during the last weeks of August. NBC News reported that the dragonfly visitation through lakefront areas would be noticeable from mid-August through September. In 2015, Chicago experienced swarms earlier than normal, causing Chicagoans great distress.
The annual migration of the Anax junius, known as the common green darner dragonfly, will bring an invasion to the Great Lakes region. In Chicago, the Michigan Lake coastline is frequented by this dragonfly, which is a large, showy insect.
Common green darners are considered to be one of the fastest flying and largest of the 5,500 varieties of dragonflies found in North America. They can grow up to 3 inches in length, with a wingspan of 4.5 inches. These insects have some clever nicknames: the mosquito hawk, lord of June, and darning needle.
Dragonfly Invasion of Chicago
Chicago’s invasion by dragonflies is not as distressing as it seems. The swarms are most commonly seen when they are hunting smaller insects that are their source of food, like gnats and mosquitoes. The water attracts the mosquitoes. Consequently, there will be other insects who feed on them in the vicinity.
When visiting Chicago in mid-August, the green darner does not typically fly over the lake, and this gives observers an impression that there is a cloud of dragonflies. The chief curator of the Peggy Notebaert Nature Museum in Chicago explained the waves of swarms seem to be everywhere but are primarily located at the edge of the lake. Doug Taron stated the number of these insects varies each year. Therefore it ‘s hard to make an educated prediction about the numbers expected.
The curator eases the minds of the curious by clarifying there is not need to be concerned about the presence of dragonflies since they cannot harm humans. They do not have stingers, as most people commonly believe. If a person were to grab one and hold it in their hands, it is possible the insect will nip at its captor, according to 5Chicago, an NBC News affiliate.
Taron suggests that if a person encounters the dragonflies in the Chicago area that they report their observations to the Migratory Dragonfly Partnership.
This is a long-term project and we are hoping to learn a little bit more about where, when and how often dragonflies travel, and eventually learn where they are going.
Green Darner Dragonfly Facts
BioKIDS website offers further information about Anax junius. These insects are active at dawn and dusk but are also visible during the day. They sleep in at night perching on plants that are close to the ground. The common green darner has four wings that move independently, thereby allowing them to move with quick agility forward and in reverse and change direction rapidly.
Some of the green darner dragonflies are migratory, whereas others are not. Those that migrate do so during mid-August through October. They move in large groups south from Northern America to Mexico. The trip may take several weeks since they stop to eat to sustain their energy. When they are sufficiently fed the Anax junius can make long migration flights. Some reports indicate that a dragonfly can travel up to 140 km per day with 900 km being the average total distance of their migration.
Northward migration begins in the spring; it is likely the offspring of those that flew south in the fall. However, this migration needs further study.
Many Native American tribes have various beliefs about these insects. The tribe native to Chicago does not report any particular beliefs surrounding dragonflies.
Native American Mythology
- The Pueblo and the Hopi consider dragonflies to be an animal of medicine. They are associated with transformation and healing. The insect’s spirit is frequently called upon by medicine women and men.
- The Pueblo also have strict taboos relating to killing one of these insects.
- In the Navajo tradition, the dragonfly symbolizes water and their images are seen in sacred sandpaintings. The image represents the element of water.
- Plains Indians value the insect as a symbol of invincibility and protection. Their images are painted on teepee covers and war shirts. It is believed this will ward off injury and danger.
- In the Northwestern tribes, the dragonfly is used as a clan crest. These are referred to as the Tlingit. Occasionally, they can be found carved on the tribes’ totem poles.
In 1997, Washington state designated the Anax junius as its official state insect. The state joins Alaska as the second to recognize the dragonfly as their state symbol.
Chicago is not the only city to be expecting this swarm of visitors in mid-August, as the green darner is migrating south from Canada and towns across the Northern United States will also be hosts to these fascinating insects.
By Cathy Milne
NBC News: Hundreds of Dragonflies Swarm Chicago Area
NBC News: Swarms of Dragonflies Expected in Chicago
WBEZ: The Great Chicago Dragonfly Invasion, explained
state symbols USA: Green Darner Dragonfly
BioKIDS: Anax junius
Migratory Dragonfly Partnership: COMMON GREEN DARNER (Anax junius)
Image by Henryhartley Courtesy of Wikimedia – Creative Commons License