The objective of bait application envisioned by early researchers was to eliminate the source of infestation, the colony, but because of the lack of adequate evaluation tools, results of field trials with mirex baits in the 1960s were mostly inconclusive. On-the-ground monitoring stations and mark-recapture protocol developed in the 1970s marked the turning point in the field studies of termite baits. Results of field studies with metabolic inhibitors and chitin synthesis inhibitors (CSIs) in the 1990s indicated that a bait toxicant has to be slow-acting and nonrepellent, and its lethal time has to be dose independent. A recent discovery that termites return to the central nest to molt and CSI-poisoned termites die near the royal pair further explains the success of CSI baits in eliminating colonies. Owing to the availability of durable baits that require less-frequent site inspection, more termite control professionals have adopted baiting systems in recent years.

The termite genus Coptotermes is both large and widespread but, as a whole, lacks robust diagnostic characters for morphological species identification. This has resulted in many taxonomic synonymies leading to the current pool of extant species a few of which are among the world’s most destructive pests of wood. The New World diversity of Coptotermes is far less complicated, but has not been the subject of critical study. Using a large collection representative of endemic Coptotermes from the region, we compared their external morphology and their 16S genetic marker sequences to identify the three described American species: C. crassus, C. niger, and C. testaceus. We found no consistent differences among populations from Mexico to Bolivia, and therefore, we reassign the former two species as junior synonyms of C. testaceus. We also compared alates and soldiers of the three non-native species of Coptotermes: C. formosanus, C. gestroi, and C. sjostedti (soldiers only) to C. testaceus and provide diagnostic characters to identify all four current New World species. An updated distribution map is provided.

The dispersal flight activity (“swarming”) of two invasive subterranean termite species, Coptotermes gestroi (Wasmann) and Coptotermes formosanus Shiraki, was monitored in metropolitan southeastern Florida, where both species are now sympatric and major structural pests. Historical records of alates collected in the area showed that the two species have distinct peaks of flight activity, from mid-February to late April for C. gestroi, and from early April to late June for C. formosanus. However, an overlap of the two dispersal flight seasons has been observed since at least 2005. The daily monitoring of dispersal flight events in southeastern Florida in 2014, 2015, and 2016 confirmed that simultaneous flights occurred several times each year. In addition, environmental conditions for favorable flights were identified, and it was established that low temperature was the primary factor inhibiting both species from dispersal flights, while all other factors had little impact on the occurrence of major dispersal flight events. However, both species shared similar temperature requirements for favorable dispersal flight conditions despite distinct peaks of activity over time. The analysis of sex ratios and average weights of the alates suggests that intrinsic colony factors are important for the timing of the maturation of alates, and that once a cohort of individuals is ready to disperse, a flight may occur as soon as the environmental conditions are favorable.

The relationship between colony size and foraging distance was examined in extended foraging arenas with juvenile colonies of the Formosan subterranean termite, Coptotermes formosanus Shiraki. Our results showed that as long as royal pairs are present, larger colonies foraged at longer distances, and the oldest workers distributed farther away from the central nest. The results agree with the scaling model that predicts a large foraging range for animals of larger body size. An analysis of published data from population survey studies and field trials of bait toxicants showed that field colonies of the eastern subterranean termite, Reticulitermes flavipes (Kollar), follow the scaling model, while C. formosanus colonies were inconsistent with the model prediction. Reasons for the inconsistency with field data of C. formosanus are discussed.

The Asian subterranean termite, Coptotermes gestroi, is a tropical species but has increasingly been collected from the subtropics in recent years, making it sympatric to the Formosan subterranean termite, C. formosanus in at least three areas, Taiwan, Hawaii, and Florida. Simultaneous flights by these two species were observed since 2013 in South Florida, during which interspecies tandems were observed. Laboratory mating of C. formosanus and C. gestroi alates produced hybrid incipient colonies of larger population size. Studies are underway to examine the presence in the field of hybrid colonies in sympatric areas of Taiwan and Florida. Other biological characteristics of C. formosanus × C. gestroi hybrids being studied include temperature tolerance and preference, colony growth rate, wood-consumption rate, and reproductive fertility. This current research aims to determine the potential establishment of a hybrid termite population in south Florida and Taiwan. It investigates the risk of introgressive hybridization in field populations, with an emphasis on its potential ecological, evolutionary, and economic consequences.