Mole crickets once were a serious problem for many Floridians. Hordes of these large, pest insects did major damage to grass and vegetables. They dug with their clawed front feet through sod farms, home lawns, golf courses, and pastures, severing grass roots and devouring grass shoots as they tunneled through the soil. On hot summer nights, gangs of mole crickets crawled and flew around, gathering at street lamps and other bright lights.
For many years, pesticides were used in an effort to combat these winged invaders. However, researchers at UF/IFAS found that biological control was a more effective way to reduce mole cricket populations. In the 1980s, researchers imported and released three specialist natural enemies of mole crickets into our state. Healthy populations of a beneficial wasp, a beneficial fly and a beneficial nematode fanned out and became established, keeping the mole crickets in check. Today it is hard to find many pest mole crickets in Florida, thanks to biological control.
This website is mainly about Florida’s three invasive species of mole crickets (Neoscapteriscus abbreviatus (Scudder), the shortwinged molecricket; Neoscapteriscus borellii (Giglio-Tos), the southern mole cricket; and Neoscapteriscus vicinus (Scudder), the tawny mole cricket) and Neocurtilla hexadactyla, the nonpest, native northern mole cricket. However, under the subheading “mole crickets elsewhere,” it includes a little information about other mole crickets in other places.
Biological control, or biocontrol, means using a beneficial species to combat a pest. Many insects have become pests in the United States because they came from other countries and had no specialized natural enemies here. With very little to keep them in check, their populations exploded. Three pest species of mole crickets, which arrived as stowaways in ships from South America in about the year 1900, are a perfect example. With one form of biological control, scientists look to the homeland of a foreign invader to find its natural enemies and then import them into our environment. The wasp, fly and nematode were all found in South America, killing these pest mole crickets but harming nothing else. Even Florida’s one native species of mole cricket, which is not a pest, is not harmed by these imported biocontrol agents.
The benefits of biocontrols are many. They are cheap to establish, safe for humans, pets, and livestock, require little to no maintenance, and do not pollute. They also are often more effective than pesticides.
Pesticides are a valid option for dealing with mole crickets — and a sometimes necessary one — but they do have drawbacks. Pesticides require regular reapplication, which costs money. They also create potential hazards. Beneficial pollinators such as bees may suffer from pesticides. Rain or sprinklers may wash pesticide runoff into groundwater, which comes up through our taps.
Biocontrols are most successful when the control is very specific to the pest. Biocontrols seek to reestablish population equilibriums rather than bombard a lawn or garden with chemicals that target every insect. The wasp, fly and nematode are a shining example of a biocontrol success story.
Do not expect biocontrol to eliminate all pest mole crickets. If all mole crickets die, then the biocontrol agents would also die. Expect instead that biocontrol will kill the vast majority (say 95 percent) of pest mole crickets, which is good enough for most purposes. On a highly maintained golf course, superintendents may want to eliminate all damage on tees and greens. They could do that by using chemicals just on the tees and greens, and biocontrol methods elsewhere. That integration of methods would be IPM.
View the following links to find out more about specific pest mole cricket biological controls: