Number Of Termites Research Articles

Escape Behavior of the Formosan Subterranean Termite (Isoptera: Rhinotermitidae) in Response to Disturbance

Disturbances to monitors and baits have often been noted as a confounding factor for the success of termite baiting systems. We studied escape behavior of Coptotermes formosanus Shiraki to a food source disturbance in the laboratory. Four peripheral chambers connected to the central food chamber through tubes served as escape routes from which escape patterns, escape and return times and differences in soldier and worker responses were recorded. We used two sand conditions: moist and dry to test whether favorable versus unfavorable conditions change escape behavior. The post disturbance responses were video recorded for 1 h. C. formosanus quickly escaped from the central chamber when disturbed. The time taken to reach the maximum number of termites that escaped ranged from 20 s to 210 s followed by a gradual return to the disturbed chamber. The majority of the escapees returned to the disturbed area within a few minutes after evacuation in both dry and wet sand conditions. A significantly higher percentage of termites escaped in wet sand arenas (43%) than in the dry sand arenas (31%). Our experiments demonstrate that C. formosanus is highly unlikely to abandon bait stations for extensive periods of time as a result of mechanical disturbances regardless of habitat quality.

Effect of Seasonal Changes in Soil Temperature and Moisture on Wood Consumption and Foraging Activity of Formosan Subterranean Termite (Isoptera: Rhinotermitidae)

The objective of this study was to determine how seasonal changes affect the foraging activity and wood consumption of the Formosan subterranean termite, Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae), in New Orleans, LA. There was a significant correlation between wood consumption and air temperature, soil temperature, and soil moisture, but not precipitation or number of rainy days. In the first year of the study, wood consumption was the lowest in December, February, and March. Wood consumption in January was not significantly different from consumption during the rest of the year. There were no seasonal changes in the number of underground monitoring stations occupied by termites. In the second year of the study, wood consumption was lowest from January to March. There was a significant decrease in the number of monitoring stations occupied by termites during the winter. This study determined that C. formosanus will remain in monitoring stations and resume feeding during warmer periods of a mild winter if average soil temperatures remain above 15 degrees C. Only prolonged periods of cold weather, with average soil temperatures below 15 degrees C, caused a significant number of termites to abandon underground monitoring stations. Seasonal changes in foraging activity would probably only disrupt baiting programs during severe winters in New Orleans, LA.

Control of Sugarcane Termites with Botanical Products

An experiment was conducted with some botanicals to find out their effectiveness against sugarcane termites and their effects on the growth and yield parameter of sugarcane at Sreepur; Gazipur; Bangladesh growers plot during the cropping seasons 2005-06 and 2006-07. The botanicals, neem leaf ( Azadirachta indica), neem seed and bishkatali (Polygonum hydropiper L.) plant powder; were applied at 60 kg per hectare, 80 kg per hectare and 100 kg per hectare during planting and then after two and four months of planting. The number of termites was higher in the control plot compared to the other botanicals treated plots. During the 2005-06 cropping season, neem leaves powder at 100 kg per hectare, neem seed powder at 60 kg per hectare, neem seed powder at 100 kg per hectare, bishkathali plant at 100 kg per hectare gave above 80 per cent efficacy with 85.09 per cent, 84.00 per cent, 809.04 per cent and 91.39 per cent. On the other hand during the 2006-07 cropping season only neem seed powder at 100 kg per hectare showed the highest efficacy with 78.77 per cent. Millable cane and yield were also increased over control. This study revealed that the botanicals from neem and bishkathali plant can be used for controlling termite. Keywords: Saccharum officinarum, botanicals, termite.

CONTROL OPTIONS FOR BANANA WEEVIL (COSMOPOLITES SORDIDUS) AND TERMITES (MICROTERMES SPP.) ON BANANA AND PLANTAIN (MUSA SPP.) IN NIGERIA

ISHS IV International Symposium on Banana: International Conference on Banana and Plantain in Africa: Harnessing International Partnerships to Increase Research Impact CONTROL OPTIONS FOR BANANA WEEVIL (COSMOPOLITES SORDIDUS) AND TERMITES (MICROTERMES SPP.) ON BANANA AND PLANTAIN (MUSA SPP.) IN NIGERIA

Termites (Isoptera) in forest ecosystems of Cat Tien National Park (Southern Vietnam)

The species composition and termite community populations were studied and the total land termites biomass was estimated in five forest habitats of Cat Tien National Park, Southern Vietnam. Twenty-four species of two families, Rhinotermitidae (1 species) and Termitidae (23 species), the predominant representatives of the subfamily Macrotermitinae, were found in mounds and in soil samples. On the test plots the density of termite mounds averaged 68 per hectare, primarily the mounds of three Macrotermes species. Destructive sampling allowed estimation of the caste composition and total community biomass based on six termite mounds of the prevailing species (Globitermes sulphureus, Microcerotermes burmanicus, Macrotermes carbonarius, M. gilvus, M. malaccensis, and Hypotermes obscuriceps). The total number of termites in the nests ranged from 65 000 to 3 150 000 individuals with the total biomass ranging from 185 to 2440 g live weight. The total abundance of nesting Macrotermes species alone could conservatively be estimated as 2.5 million individuals and 20.5 kg live weight per hectare. The number of soil- and litter-feeding termites averaged for the test plots was estimated at about 60 ind./m2. Four species dominating on the test plots (M. carbonarius, M. gilvus, M. malaccensis, and H. obscuriceps) belong to active tree litter feeders.

Relation between termite numbers and the size of their mounds

This article provides a meta-analysis of quantitative data available in literature regarding the relation between termite numbers and the volume of their mounds for 24 species belonging to 13 genera. The leading question behind this analysis is: “how do the respiratory gas exchanges regulate the size of termite mounds?” This question is answered through the analysis of the log–log regression between the volume of the mound and the number of inhabitants. The most confident data support the hypothesis of a respiratory regulation that can be achieved through a relation between the termite numbers and (1) the volume of their mounds (slope of the regression near 1, Noditermes), (2) the surface of the outer walls of their mounds (slope of the regression near 0.67, Termitinae and Nasutitermes) or (3) a compromise between the surface of the outer walls of their mounds and some linear structures of their nests (slope of the regression between 0.67 and 0.33, Trinervitermes and Macrotermes). The way this is achieved is linked with the architecture of the mound. A confident relation was found between the number of individuals and the epigeal volume of their mounds for 18 species for which the most reliable data were provided. Three more accurate models are proposed for estimating the termite population based on the nest material and architecture and on the size of the termites.

Laboratory evaluation of the resistance of plastics to the subterranean termite Coptotermes formosanus (Blattodea: Rhinotermitidae)

Since preliminary studies demonstrated unsuitability of the existing Japanese standardized methods for evaluating the termite-resistance of plastics, a new laboratory method was tested for its applicability. Assembled units, each consisting of a plastic material and a wood attachment surrounding a plastic sample, were placed around a laboratory nest of Coptotermes formosanus for 6 weeks at 28 ± 2 °C and over 80% relative humidity, and the termite attack was assessed visually. Amorphous polyamide performed best, and low-density polyethylene did worst. This new laboratory method succeeded in demonstrating termite damage to materials that are susceptible under actual service conditions, although it is not applicable to evaluating insecticide-incorporated plastics. A modified JWPA Standard No. 17 test method was employed to determine the minimum number of termites required to attack high-density polyethylene film so that it was possible to standardize the method to compare termite-resistance of non-woody materials with or without chemical treatment. It was concluded that 300 workers of C. formosanus in 12.6 cm 2 of foraging area, which was equivalent to the termite density (pressure) of 24 workers cm −2 foraging area, were required for termites to attack from a straight scratched surface.

Estimating the population size of subterranean termites by using a novel diffusion-based method

We developed a population size estimation method to account for the unequal recapture probability of marked animals when their diffusion has not yet to reach the equilibrium in a two-dimensional closed system [S.-H. Lee, N.-Y. Su, Estimating the size of a closed population from a single mark–recapture regime by using a diffusion probability of marked individuals, Appl. Math. Comput. 182 (2006) 403–411]. In the present study, we transformed the method to one-dimensional form and applied it to the quasi one-dimensional artificial colony of the Formosan subterranean termite, Coptotermes formosanus Shiraki. On the whole, the population estimates were consistent with the known number of termites in the artificial colony. This result strongly supports that our method can be useful tool to estimate the closed population size during the diffusion of marked animals.

Field Evaluation of Potential Control Strategies Against the Invasive Eastern Subterranean Termite (Isoptera: Rhinotermitidae) in Chile

Four different termite control strategies consisting of two soil treatments with cypermethrin and fipronil and two bait treatments with hexaflumuron and sulfluramid were evaluated for their efficacy and potential for controlling the invasive eastern subterranean termite, Reticulitermes flavipes (Kollar) (Isoptera: Rhinotermitidae), in Quillota and Valparaíso, Chile. Monitoring stations were installed at all sites to measure the overall termite activity next to and at distances up to 30 m away from infested structures, most being 3–5 m. Foraging activity was extremely seasonal with the maximum consumption rates occurring from January to April. Termite foraging activity was low from July to September. After treatments in January 2003, there was a significant decrease in wood consumption, percentage of active stations, and numbers of termites in traps for the first 6 mo with hexaflumuron baits. No significant change in R. flavipes foraging activity was observed on wood consumption and percentage of active stations for sulfluramid bait or cypermethrin and fipronil soils treatments. The seasonal pattern of foraging activity remained unchanged for all treatments in 2004 and 2005, except structures baited with hexaflumuron. Feeding activity at the monitors in the area surrounding the hexaflumuron baits declined to 0 after January 2004. Alate flights occurred in ≈38% of the structures treated with cypermethrin and sulfluramid bait in 2003 and in ≈40% of the structures treated with cypermethrin, fipronil, and sulfluramid bait in 2004. Sulfluramid baits and cypermethrin soil treatments did not have any impact within a 15-m radius of the structures. Soils treatments of fipronil and cypermethrin prevented termites access in 75% of the homes. The number of active monitoring stations only declined within 2 m of the fipronil-treated zone. Hexaflumuron exhibited a reduction in activity for at least a 15-m radius.

Field Evaluation of Potential Control Strategies Against the Invasive Eastern Subterranean Termite (Isoptera: Rhinotermitidae) in Chile

Four different termite control strategies consisting of two soil treatments with cypermethrin and fipronil and two bait treatments with hexaflumuron and sulfluramid were evaluated for their efficacy and potential for controlling the invasive eastern subterranean termite, Reticulitermes flavipes (Kollar) (Isoptera: Rhinotermitidae), in Quillota and Valparaiso, Chile. Monitoring stations were installed at all sites to measure the overall termite activity next to and at distances up to 30 m away from infested structures, most being 3-5 m. Foraging activity was extremely seasonal with the maximum consumption rates occurring from January to April. Termite foraging activity was low from July to September. After treatments in January 2003, there was a significant decrease in wood consumption, percentage of active stations, and numbers of termites in traps for the first 6 mo with hexaflumuron baits. No significant change in R. flavipes foraging activity was observed on wood consumption and percentage of active stations for sulfluramid bait or cypermethrin and fipronil soils treatments. The seasonal pattern of foraging activity remained unchanged for all treatments in 2004 and 2005, except structures baited with hexaflumuron. Feeding activity at the monitors in the area surrounding the hexaflumuron baits declined to 0 after January 2004. Alate flights occurred in approximately 38% of the structures treated with cypermethrin and sulfluramid bait in 2003 and in approximately 40% of the structures treated with cypermethrin, fipronil, and sulfluramid bait in 2004. Sulfluramid baits and cypermethrin soil treatments did not have any impact within a 15-m radius of the structures. Soils treatments of fipronil and cypermethrin prevented termites access in 75% of the homes. The number of active monitoring stations only declined within 2 m of the fipronil-treated zone. Hexaflumuron exhibited a reduction in activity for at least a 15-m radius.

Mark–recapture without estimating population sizes: a tool to evaluate termite baits

The mark-recapture technique is currently being used by many termite researchers. Here its two uses are explained and disentangled. Use 1 is mapping the geographical location of the colony and use 2 is estimating the number of termites in the colony. Use 2 is controversial because the accuracy of the estimates has been widely questioned. In this article, it is explained that use 1 is not controversial and that use 1 (not use 2) is the criterion that is currently being used for evaluating the efficacy of termite baits.

Estimating tree resin dose effect on termites

The aim of this study is to determine the effectiveness of a natural tropical tree resin in controlling termites thus providing protection from their destruction. Tree resin from the bark of tropical trees offers the potential for this protection. Termites were fed by filter paper soaked in tropical tree resin dissolved in a solvent at different concentrations for 15 days. The number of termites still alive on each day was observed and recorded. In this paper, we use four types of statistical models: Partially linear model, piecewise linear model, cubic smooth spline and mixed effect model to analyze the termite data. The results show that tropical tree resin, particularly at a higher concentration of 10 mg is significantly more effective in killing termites. We show that two dishes under 10 mg of tree resin were mistaken since the data for these two dishes are shown insignificantly different from data under 5 mg. The partially linear model shows that there is non-linear (piecewise linear) time effect. Both piecewise linear model and cubic spline smoothing show that the most effective period is the first week. The non-parametric smoothing, cubic spline, and piecewise linear model are not significantly different. Mixed effect model is consistent with partial linear model and piecewise linear model. The estimated treatment effect is time varying with a change point at day 7. Therefore, we suggest the piecewise linear model as the final simplest one for prediction. This model fits the data with adjusted R2 = 93.7 per cent and shows that on average, 10 mg is 68.9 per cent more efficient than 5 mg in killing termites during the first week. Copyright © 2005 John Wiley & Sons, Ltd.

The emergence of collective foraging in the arboreal Gnamptogenys menadensis (Hymenoptera: Formicidae).

Gnamptogenys menadensis is an arboreal nester that forages opportunistically almost exclusively on vegetation, sometimes recruiting others to participate in prey retrieval. The three-dimensional characteristics of vegetation suggest that functions describing recruitment decision thresholds or the pattern of recruitment in arboreal species may differ from those predicted by optimal foraging theory. To examine the effects of prey abundance and distance on the recruitment dynamics of G. menadensis, we baited nests with one termite, five termites or a number of termites between 20 and 40 either near to or far from the entrance and observed the ensuing behaviors. G. menadensis recruited others when encountering multiple termites regardless of the termite pile's distance from the nest, although a few individuals remained at the site and defended the resource. The pattern of arrivals at the site indicates that the majority and sometimes all arrivals were recruited from the branch trails. In combination, these results suggest that the architecture of the foraging habitat, which limits available return routes to the nest and thus increases encounter probabilities with potential recruits, shaped the process of information transfer and generated a collective pattern of foraging and prey retrieval.

Interhabitat differences in ant activity on plant foliage: ants at extrafloral nectaries ofHibiscus pernambucensisin sandy and mangrove forests

AbstractThe association between visiting ants and the extrafloral nectaries (EFN)‐bearing shrubHibiscus pernambucensisArruda (Malvaceae) was investigated in two different coastal habitats – a permanently dry sandy forest and a regularly inundated mangrove forest. In both habitats the frequency of plants with ants and the mean number of ants per plant were much higher onH. pernambucensisthan on non‐nectariferous neighbouring plants. In the sandy forest the proportion of live termite baits attacked by ants onH. pernambucensiswas much higher than on plants lacking EFNs. In the mangrove, however, ants attacked equal numbers of termites on either plant class. Ant attendance to tuna/honey baits revealed that overall ant activity in the sandy forest is higher than in the mangrove area. The vertical distribution (ground vs. foliage) of ant activity also differed between habitats. While in the mangrove foraging ants were more frequent at baits placed on foliage, in the sandy forest ant attendance was higher at ground baits. Plants housing ant colonies were more common in the mangrove than in the sandy forest. Frequent flooding in the mangrove may have resulted in increased numbers of ant nests on vegetation and scattered ant activity across plant foliage, irrespective of possession of EFNs. Thus plants with EFNs in the mangrove may not experience increased ant aggression towards potential herbivores relative to plants lacking EFNs. The study suggests that the vertical distribution of ant activity, as related to different nest site distribution (ground vs. foliage) through a spatial scale, can mediate ant foraging patterns on plant foliage and probably affect the ants’ potential for herbivore deterrence on an EFN‐bearing plant species.

Prey manipulation in a grassland community at an inland airport in South Africa

Terrestrial invertebrates and very small vertebrates were collected using pitfall and mouse traps in undisturbed long grass and grass which were kept permanently short over a period of 15 months (March 1994 – May 1995) at the Bloemfontein airport. Numerically insects contributed more than 90% of the overall sample. Twice as many individuals occurred in short grass compared to those in the long grass. The available food source for predominantly insectivorous avifauna at inland airports can thus be effectively reduced (indirectly also bird numbers) by implementing a so-called long grass policy as a control strategy. A significant and sustainable decrease in harvester termite numbers and activities was accomplished by administering bait treated with Gaucho in disturbed grass areas. As an important component in the diet of birds in grassland communities, bird numbers, and hopefully also bird aircraft strikes, can thus be reduced.

Estimating relative decline in populations of subterranean termites (Isoptera: Rhinotermitidae) due to baiting.

Although mark-recapture protocols produce inaccurate population estimates of termite colonies, they might be employed to estimate a relative change in colony size. This possibility was tested using two Australian, mound-building, wood-eating, subterranean Coptotermes species. Three different toxicants delivered in baits were used to decrease (but not eliminate) colony size, and a single mark-recapture protocol was used to estimate pre- and postbaiting population sizes. For both species, the numbers of termites retrieved from bait stations varied widely, resulting in no significant differences in the numbers of termites sampled between treatments in either the pre- or postbaiting protocols. There were significantly fewer termites sampled in all treatments, controls included, in the postbaiting protocol compared with the pre-, suggesting a seasonal change in forager numbers. The comparison of population estimates shows a large decrease in toxicant treated colonies compared with little change in control colonies, which suggests that estimating the relative decline in population size using mark-recapture protocols might to be possible. However, the change in population estimate was due entirely to the significantly lower recapture rate in the control colonies relative to the toxicant treated colonies, as numbers of unmarked termites did not change between treatments. The population estimates should be treated with caution because low recapture rates produce dubious population estimates and, in some cases, postbaiting mark-recapture population estimates could be much greater than those at prebaiting, despite consumption of bait in sufficient quantities to cause population decline. A possible interaction between fat-stain markers and toxicants should be investigated if mark-recapture population estimates are used. Alternative methods of population change are advised, along with other indirect measures.

Effect of Organic and Inorganic Landscape Mulches on Subterranean Termite (Isoptera: Rhinotermitidae) Foraging Activity

This research investigated whether organic and inorganic landscape mulches, which buffer soils against temperature extremes and desiccation, create conditions conducive to subterranean foraging by Reticulitermes virginicus (Banks). In the field, termite activity was measured with cardboard monitors placed beneath and within plots of eucalyptus, hardwood, pine bark, and pea gravel mulches, and bare ground (control). Gravel mulch provided higher feeding rates in underground monitors. Groundcover type had no significant effect on the number of monitors discovered by termites or the number of termites within each monitor. All groundcovers significantly reduced the temperature of the soil surface compared with bare soils, but temperature and moisture levels 12 cm below mulch-covered surfaces were not significantly different from those beneath bare soil. In the laboratory, R. virginicus were fed one of the three organic mulches or a control diet of white birch, Betula papyrifera (Marsh), as their only food source. All diet types were consumed at equivalent rates, but the mulch-fed termites suffered significantly lower survivorship.

Solid-phase microextraction for the detection of termite cuticular hydrocarbons

Solid-phase microextraction (SPME)–gas chromatography–mass spectrometry was used to identify the cuticular hydrocarbons of the subterranean termite Coptotermes formosanus Shiraki. Headspace SPME and direct contact SPME methods were evaluated and compared to the hexane extraction method. Variables, such as temperature, time, number of termites, condition of the termites, and the type of SPME fiber were evaluated. Methods were refined to increase the reproducibility as well as the sensitivity. Both SPME methods were successfully used for the identification of all the major termite cuticular hydrocarbons. Using the headspace SPME method, other compounds of interest could also be identified, such as fatty acids. Using the direct contact SPME method, termites could be repeatedly studied over time to monitor chemical changes.

The recolonization of the Krakatau islands by termites (Isoptera), and their biogeographical origins

The termite assemblages of the Krakatau islands and five sites in Sumatra and Java were investigated, using a standardized transect sampling method. Five species were found on the Krakatau islands that have not been collected there before. The total number of termites recorded on the islands since the 1883 volcanic eruption is now twelve species, all of which are wood feeders. No termites nesting in or feeding on the soil were found on the Krakataus, suggesting that rafting in wood is the primary method by which the termites recolonized the islands.

The recolonization of the Krakatau islands by termites (Isoptera), and their biogeographical origins

The termite assemblages of the Krakatau islands and five sites in Sumatra and Java were investigated, using a standardized transect sampling method. Five species were found on the Krakatau islands that have not been collected there before. The total number of termites recorded on the islands since the 1883 volcanic eruption is now twelve species, all of which are wood feeders. No termites nesting in or feeding on the soil were found on the Krakataus, suggesting that rafting in wood is the primary method by which the termites recolonized the islands.