Clouds of "lovebugs" swarm over Beaufort in May to April and mid-September to October each year. Dr. Timothy A. Mousseau of the University of South Carolina says that "many people don't realize that these flies are actually invaders from Central America and have been working their way northward along the coast". The invasion began around 1920, and winds first carried the insects to Louisiana (there is no truth to reports that lovebugs were introduced to the United States by misguided insect researchers).
Lovebugs are now found from Costa Rica, Guatemala, Honduras and Mexico to South Carolina, Georgia, Florida, Alabama, Louisiana, Mississippi and Texas. They are not true "bugs", despite the "lovebug" nickname (the scientific name is Plecia nearctica, of the same Order Diptera as house flies and mosquitoes, so the insects other nickname -- "honeymoon fly" is more apt). Though scientists have identified more than 200 species in the genus Plecia, only two species fly around the United States. Plecia americana is the second species, ranging from North Carolina to Mexico and appearing only in April, May, and June. This woodland insect stays away from highways.
According to Simon and Schusters Guide to Insects, the mowed grass rotting along interstate highways have been the ideal breeding ground for lovebugs. The larvae also develop under cow manure. Generous rainfall and mild winter temperatures increase the lovebugs' numbers, and the rains from September 1999's Hurricane Floyd accounted for a bumper crop of these "honeymoon flies" in the South Carolina Lowcountry. So with fewer owners now burning off their woodland properties each year and more cattle in bigger and better pastures, numbers of lovebugs are sure to grow.
It should come as no surprise that the nickname comes from the lovebugs habit of mating while coupled in midair. The males' eyes are four times larger than the females', the better to spot a mate in the swarm. Up to eight males may compete for a single female. Females are the larger partner and live for only 72-86 hours (the males last nearly 92 hours). Pairs stay coupled for about 56 hours (successful fertilization taking about 12 ½ hours), though larger male rivals may disrupt and separate the couples. Mating lovebugs do not appear to uncouple in flight or at night, and will continue to feed (on nectar or pollen) during their couplings. The male tranfers not only sperm, but also protein and sugar to nourish the female and her 152 to 600 eggs ("The male is an empty shell afterwards," said Mousseau).
Lovebugs may reach a height of 1500 feet in flight. It is apparently the larger female who does the flying for the couple. Each generation cycle lasts about four weeks.
Though lovebugs do not sting, bite, or carry disease, they do spatter thousands of auto windshields and clog countless radiators. "They are drawn to vehicle vibrations and fuel vapors exposed to sunlight," wrote Bradenton (Florida) Herald reporter Brian Neill, "and they prefer diesel fuel over regular gasoline. " Mousseau doubted that fuel vapor attracts lovebugs, however. He believed that lawn mowers stir up lovebugs that are hiding in the grass, and vehicles hit insects that are on their way to lay eggs along the damp roadsides. Heat from auto engines may also attract lovebugs.
Decaying lovebugs release a mild acid that can etch auto paint surfaces, especially when bacteria is left to interact with the "gunk". The best remedy is to soak the car surface with water and apply 15 to 20 minutes of "elbow grease". The maligned lovebugs also play a helpful role: their larvae help to recycle decaying organic matter.
Hungry birds are the lovebugs natural enemies, but the insects are hard to control. Chemicals dropped by airplanes in the late 1960s killed few bugs and cleared the highways for only a half hour. Though a type of fungus has killed up to one third of larvae in a more recent test, researchers are far from any real solution to the lovebug problem.
And pity poor Florida! In addition to the big "plagues" in the spring and fall, small numbers of lovebugs have been spotted there every month except November.
The University of Florida and the Florida Department of Agriculture and Consumer Services maintain an in-depth page about lovebugs on its "Featured Creatures" site http://edis.ifas.ufl.edu/IN204 , the source of much of this web page.
"Love Bugs Love
Wetter Weather" by Lynne Langley, in the September 24, 1999