Rain after dry spell increases cricket counts

On the walls of buildings or on sidewalks throughout town, you might notice little black insects hopping around. The small critters are crickets, and they can be found all over the place, especially during this time of year.

Justin Hale, ag and natural resources agent with Texas AgriLife Extension Service in Johnson County, said cricket outbreaks come from dry springs and summers, like we’ve experienced lately.

“Extension entomologists speculate that this gives more of the eggs laid by crickets a better chance to complete their lifecycle and develop into the adults we see,” Hale said. “The start of the outbreak starts this time of year — around August and September — when we have  precipitation and a cool snap from the weather we have been having.”

After several weeks of no rain, Gayle White of Cleburne — who has an official weather gauge from NBC DFW — measured 6.23 inches of rain over the weekend. 

Although the cricket species associated with outbreaks in Texas haven’t been well studied, most belong to the Gryllus assimilis complex and are collectively referred to as black field crickets or field crickets, according to AgriLife.

“Field cricket eggs are laid in the fall, approximately two weeks after females mature and develop wings,” according to AgriLife. “Firm, bare soil sites are preferred for egg-laying. A single female cricket may lay from 150-400 eggs. Eggs remain in the soil throughout the winter and hatch the following spring.”

Cricket outbreaks occur when large numbers of nymphs complete their development and embark on nighttime mating flights, according to AgriLife. 

“The largest cricket outbreaks seem to occur during years of dry springs and summers,” according to AgriLife. “The reason for cricket outbreaks under such conditions is not fully understood; however, less fungal disease among eggs and cricket nymphs may provide a partial explanation. Although crickets can be locally abundant in any year, numbers appear to be highest in August and September when a summer drought is broken by rainfall and cooler weather.”

Field crickets mostly live outside, but sometimes they find their way indoors. 

“Indoors, crickets may damage clothing, drapes or wall coverings with staining from feces or vomitus, or by their feeding activities,” according to AgriLife. “Although crickets do not normally feed on fabrics, soiled clothing or clothes stained with perspiration may be damaged by crickets.” 

Hale said residents don’t have to worry about crickets carrying diseases, but they can be a nuisance sometimes. 

Outdoor lighting can attract them around homes and commercial buildings, and reducing the amount of outdoor light can keep hordes of them collecting in those areas, according to AgriLife. 

Potential areas where crickets can gain entry into a home — including door thresholds, weep holes, soffits along the eaves of homes, windows and garage doors — must be sealed tightly to keep the insects out. 

“Steel or brass wool may be stuffed in weep holes as temporary insect barriers, while allowing continued air circulation,” according to AgriLife. “Door sweeps consisting of nylon bristles or rubber seals can often be installed quickly and provide a dramatic reduction of crickets entering schools and other commercial buildings.”

The insects can be killed with any of several insecticidal baits and sprays, Hale said. Baits are granular products that include a food that tastes good to them. They should be applied to ground covers and other areas where they are congregating next to buildings. 

For more information about crickets, visit citybugs.tamu.edu/factsheets/household/misc-house/ent-2003.