The Big Dipper
If you've ever spent time catching fireflies, chances are you have caught a "big dipper." This is the most common firefly throughout most of the Midwest, and the most common of the more than 40 species of fireflies found in Indiana. The big dipper firefly, Photinus pyralis, is commonly seen above lawns, meadows, and along roadsides, and now also will be seen lighting the way across North America on the sides of more than 1,900 U-Haul trucks. Big dipper fireflies were given the nickname because of their flash patterns. When producing light, male fireflies will first hover then when the flash happens, they drop down slightly. After the drop, they then have a forward rising flight movement resulting in a J-shaped pattern that when flashing looks like the Big Dipper constellation.
Turpin explains that big dippers begin lighting up a yellowish flash at dusk, each of which lasts anywhere from .50 to .75 seconds, and hovers between two to three feet above ground before and after producing a flash. Because of this, Turpin says, "most children who engage in the great firefly chase fill their bug jars with these so-called big dippers." However, Turpin also notes that although easy to catch, big dippers do not generally flash very much when placed in a jar. Research has shown that some species of fireflies have declined in population; however, the big dipper firefly probably has benefitted from the clearing of forests in eastern North America and is more widespread now than in historical times.