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The hypothesis that western drywood termite, Incisitermes minor (Hagen), nymphs are negatively phototactic was tested. Significantly more nymphs were found under the covered half of a petri dish than under the uncovered half exposed to either incandescent or fluorescent light, whereas there was no significant preference for either the covered or uncovered side when exposed to red darkroom light. The behaviors of I. minor nymphs when placed on temperature gradients for 24 h at 10, 30, or 50% RH were videotaped, analyzed, and quantified to test the hypothesis that I. minor nymphs actively avoid and move away from hot and cold temperatures. I. minor nymphs avoided temperatures >45°C and

Colony size, foraging activity, foraging phenology, and selected physiological parameters were evaluated on colonies of the western subterranean termite, Reticulitermes hesperus Banks, in urban and undisturbed habitats. The greatest foraging activity occurred from May to October at the University of California, Riverside urban site, and from late November to January at the Motte–Rimrock natural study site. Foraging activity was related to minimum temperatures at the urban site, and minimum temperatures and precipitation at the undisturbed site. Foraging population was greater in the urban habitat, with estimates ranging from 85,752 to 830,581 foragers compared with 78,930 to 103,758 at the native site. Termites at the urban site had greater initial and dry body weights, but less body fat than their counterparts from undisturbed habitats. No difference in the cuticular permeabilities of termites occurred between locations.

Some abiotic environmental factors influencing the survival of the cat flea, Ctenocephalides felis (Bouche), in semi-arid and temperature climates were studied. Pupae survived outdoors throughout most of the year except July and August, when temperatures often exceeded 35°C. As temperatures increased, the time required to kill larvae exposed to 12 and 33% relative humidity (RH) decreased. At 27°C, 16-h exposures to 12% RH and 24-h exposures to 33% RH provided 100 and 97% mortality, respectively. Larvae survived only when the RH was >50% for several consecutive days or the microhabitats provided substantially higher than ambient humidity. Soil moistures of 1 to 10% permitted larval development even when larvae were held at 12 ± 2% RH. Soil moistures from 20 to 50% were deleterious. Emerged and preemerged adults survived short exposures to low temperatures but were killed by 10-day or 5-day exposures at 3 and −1°C, respectively. Exposures to 3°C for 5 days killed all immature stages.

Aspects of the outdoor activity and distribution of the smokybrown cockroach, Periplaneta fuliginosa (Serville), were studied during a 14-day period in July 1984 in Houston, Tex. Daily trapping revealed an age-class distribution of 27.2% adults (260 females : 244 males) and 72.2% nymphs (630 small : 475 medium : 214 large). Trap-catch was significantly lower following rains and correlated to the time when it rained. Rain early in the day resulted in higher trap-catches than rains occurring later in the day. The mark-recapture technique was used to estimate adult population size, movement, and home range. Of 240 females and 206 males marked and released, 12.1% and 7.3%, respectively, were recaptured at least once. A mean of 338 female and 386 male P. fuliginosa was estimated living on the 0.23-ha study site. Of recaptured adults, 34.3% of the females and 58.8% of the males moved at least 2 m. Mean circular home ranges were 107 m2 for females and 280 m2 for males. Traps located near harborage sites caught >70% nymphs, whereas other traps caught

The alarm pheromone of southern California populations of the ant Forelius foetidus (Buckley) was identified as 2-heptanone. This compound (2.9µg per worker) occurs in an admixture with cis, trans-iridodial and a minor unidentified iridodial isomer, which together constitute a defensive secretion emitted posteriorly from the gaster. Secretory components were isolated and quantified from extracts by gas chromatography and structurally elucidated by 1H and 13C nuclear magnetic resonance analyses. Videorecordings of agonistic encounters with foreign ants revealed a stereotypical defense behavior of F. foetidus workers culminating in aerial transfer of their secretion onto the heterospecific worker. The defensive spray was repellent but not toxic to either Solenopsis maniosa or Crematogaster califomica Chemical and behavioral comparisons between F. foetidus and F. (=Iridomyrmex) pminosus indicate a high degree of similarity between these sympatric ants and support the generic reclassification of the latter species.