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Within the cattle fever tick quarantine zone along the Rio Grande, a steady displacement of native vegetation by Arundo donax L. has been occurring for over a century. Arundo rapidly grows to a height of 3-6 m creating a dense wall of vegetation impeding surveillance and interception of stray cattle breaching the cattle fever tick quarantine from Mexico. Additionally, arundo monocultures may decrease the number and diversity of predatory beetles feeding on cattle fever ticks. To compare predatory beetle abundance and diversity within and between arundo and native vegetation, beetles were trapped at 10 locations twice a month for 16 mo (=38,400 trap nights) in the cattle fever tick quarantine zone along the Mexico-American border between Brownsville and Del Rio, TX. In total, 766 beetles were trapped, which included 34 genera and 43 species. Native vegetation provided more beetles, greater species richness, and increased biological diversity. Thus, greater beetle diversity was found in the more complex native vegetation compared with arundo stands. However, because predatory beetle sample numbers were modest, it is unlikely these mostly polyphagous, opportunistic arthropod predators would apply much pressure on tick populations, leading us to conclude that beetle predation would have little effect on tick populations in native vegetation or within stands of arundo.

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This laboratory study reports the ability of Formosan subterranean termite, Coptotermes formosanus Shiraki, colonies to survive for at least 9 yr while restricted to a sweater box. Colonies survived by limiting queen size and worker numbers, allowing these bonsai colonies to thrive. Queen physogastry appeared to plateau with 9-yr-old queens not larger than 6-yr-old queens, but nearly triple the size of 2-yr-old queens. Nine-year-old colony worker numbers were not greater than 6-yr-old colonies, but worker numbers were greater than in 2-yr-old colonies. Such colony survival under conditions of restricted resources provides a mechanism for re-infestation of areas following extensive area-wide control efforts. "Bonsai" colonies are relevant to the ability of marginalized colonies to avoid detection and then expand and invade into areas once the large, mature colonies are eliminated, and their potential to produce alates to start new C. formosanus colonies in areas which have been subjected to colony elimination programs impacts termite management strategies.

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This field study investigated the colony effect of a fipronil spot treatment applied to active infestations of Formosan subterranean termite, Coptotermes formosanus Shiraki. Spot treatments were applied to a single active independent monitor from each of four colonies in which multiple independent monitors were established. All treated monitors were abandoned, and the contents of the treated monitors were replaced with untreated wood at the approximately 30-d posttreatment inspection. All colonies survived treatment and only one colony exhibited long-term effects, which included significant reductions in termite collections and increased worker size. The affected colony was treated within 1 m of its primary nest. Two colonies exhibited a correlation between monitor termite production and distance from treatment. Distance appears to be a factor limiting fipronil's colony effects. The Formosan subterranean termite may not be a good candidate for the exterior perimeter and localized interior treatment label option because of the large range and size of the colony.

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This study examined the effect of diet, experimental design, and length of time in the laboratory on intercolonial agonism among Formosan subterranean termite, Coptotermes formosanus Shiraki, colonies. In pairings of 12 C. formosanus Shiraki colonies collected in an urban forest, there was no significant reduction in survival of termites in 30 out of 59 colony pairs compared to colony controls, but there was <50% survival in 18 colony pairs and <10% survival in six colony pairs. There was no correlation between the level of aggressive behavior and the laboratory diet of the termites. Effect of bioassay design and length of time in the laboratory was evaluated in three colony pairs where tests were first conducted on the day of field collection, then colony pairs were retested every 7 days. Aggressive behavior decreased over time in both bioassays, but it tended to decrease more rapidly in the Petri dish tests. The rapid loss of agonism in groups of termites kept in the laboratory demonstrates that changes in environmental factors affect intercolonial agonism.