[Image: Winged Formosan subterranean termite]
Formosan subterranean termites swarm annually from well-established colonies each April through July in southern Louisiana. LSU Agricultural Center researchers have collected numbers and maintained records on daily flights and total swarmers caught in light traps in and around New Orleans since 1989. A large growth spurt in alate swarmers was recorded between 1989 and 1998, with all but one year showing an increase over the previous year (that occurred with the 1997 swarm).
The average alate (winged reproductive) collection among the 15 light traps (Bioquip brand) in 1998 was 16,000 individual swarmers. This information is used to observe patterns in both yearly population numbers and daily flight rhythms by our research team. A pattern in daily rhythms among all years examined show an amazing consistency of when large flights will occur in each flight season. A better understanding of the mechanisms regulating flights by Formosan termites may lead to better control measures.
Provided below are the daily counts for 1989-2003. The timing of the flight appears to have extrinsic and intrinsic control mechanisms, but no strong correlations have been found. Note: Some data for flights in 2000 are missing.