Mud Tubes Research Articles

Chemical Ecology, Detection and Identification of Subterranean Termites Based on Electronic-Nose Volatile Emissions Analysis

The effective monitoring and identification of existing subterranean termite populations within coarse woody debris and infested wood in service depend on accurate detection. These insects are often concealed within logs, wooden support structures, walls, and floorboards of buildings. In the absence of external mud tubes, termite infestations normally must be discovered through the destructive exploration of wooden structures to reveal the physical presence of these insect pests. Subterranean termite species are difficult to identify due to similarities in morphological features, but they may be readily distinguished by differences in volatile emissions from which they are divided into chemotaxonomic groups. Consequently, a more effective and nondestructive approach for detection and identification is to take advantage of unique species-specific emissions of volatile organic compounds (VOCs) from termite bodies which easily pass through wooden structures, allowing for detection without physical damage to wood and avoiding expensive DNA analysis. Electronic aroma detection analyses were conducted with an Aromascan A32S electronic-nose (e-nose) instrument, fitted with a 32-sensor conducting polymer (CP) sensor array, for discrimination between four common subterranean termite species based on differences in volatile emissions. Principal component analysis (PCA) of whole-body volatiles effectively distinguished between four termite species with the first two principal components accounting for more than 98% of sample variance (p < 0.01). Unique electronic aroma signature patterns (smellprints) were produced from e-nose sensor array outputs that allowed for the effective identification of termite species based on distinct differences in volatile metabolites released from their bodies. The e-nose methods were determined to be an improved means for rapidly detecting and monitoring termite species in wood. The method is cheaper than conventional detection methods and allows for the timelier discovery of species-specific termite infestations necessary for better management. The e-nose capability of detecting the Formosan termite in indoor living spaces was particularly significant due to the production of naphthalene, a volatile hazardous gas causing many adverse human health effects in enclosed environments.

Kehadiran Rayap dan Tanda-Tanda Infestasinya pada Bangunan Rumah Di Kawasan ‘Kebun Karet’ Gundaling, Tamiang Layang, Barito Timur, Kalimantan Tengah

Land clearing carried out in part or all of the ‘Rubber Garden’ area for settlement often leave stumps and branches that becomes food sources for termites and when the food sources is ran out, termites attack extends to the wooden structure of the house building and becomes a destructive pest. The aim of this research was to detect the presence of termites through signs of infestation on house building and yard located in the Gundaling ‘Rubber Garden’, Barito Timur Regency. Twenty house buildings were observed. Visual detection of termite infestation signs was conducted on house building and yard such as on wooden building components, fuel wood, stump, dead and living trees, and recording wooden building components damaged by termite infestation. Termites specimens were collected by directly capture termites from mud tubes and nests on the observed house buildings and yards. The results showed the presence of termites from the genus Nasutitermes on house buildings through signs of infestation in the form of mud tubes, carton nests, and damaged wooden building components. In the yard, the genus Nasutitermes was found through signs of infestation in the form of a mud tubes, arboreal carton nest, while the signs of termite infestation of genus Coptotermes was in the form of shelter tubes.

Polydorid species (Annelida: Spionidae) associated with commercially important oyster shells and their shell infestation along the coast of Normandy, in the English Channel, France

Polydorid species (Annelida, Spionidae), which inhabit the shells of the commercially important oyster Crassostrea gigas, were investigated along the coast of Normandy, France. Eight species, including five new records for Normandy (Polydora onagawaensis, Polydora websteri, Boccardia pseudonatrix, Boccardia proboscidea, and Boccardiella hamata) and two first records in European waters (P. onagawaensis and B. pseudonatrix), were identified based on morphological, molecular biological, and ecological characteristics. Polydora onagawaensis, which belongs to the Polydora ciliata/websteri complex, was discovered in the shells of wild and suspended cultured oysters, as well as in limestone substrates. In the phylogenetic analysis of mitochondrial COI gene sequences, specimens of P. onagawaensis collected from Normandy were grouped together with specimens from the USA into a single clade and were distinguished from the other three lineages that comprised Japanese and USA specimens. Polydora websteri inhabited shells of suspended cultured oysters. Polydora hoplura, Dipolydora giardi, and Dipolydora sp. were observed in shells from the sandy oyster culture grounds. Boccardiella hamata has been found in wild oyster shells from muddy oyster culture grounds. Boccardia pseudonatrix was observed in the shells of both the wild and cultured oysters. Adult and juvenile Boccardia proboscidea were observed in coralline algae, as well as in suspended cultured oysters. Mud tubes were observed to protrude from the outer surface of the shells, and abnormal black and calcareous deposits were secreted on the inner surface of the shells against polydorid penetration.

Repairing Behavior of Termites Odontotermes obesus (Rambur), (B lattodea: Termitidae) in Response to the Damage of Indoor Mudtube

The termite Odototermes obesus (Rambur) either tunnel through soil or move inside the ‘mudtube’ usually found on walls or in cracks between boards and walls. The mud tube formation could provide the initial proof of the termite infestation. The study analyses the behavioral changes of termite when the indoor mud tube was damaged. The response of termites was recorded by video camera at certain intervals until the mud tube was repaired and closed. Seasonal effects on repairing of damaged mud tube by termite indicated that during rainy season the time required for repairing an unit area of indoor mud tube was about half of the summer season. Based on change of behavioral patterns due to the damage of mud tube the responses of the termites were divided into 6 different categories which reflected the different division of labors that were distributed among the workers after sudden disturbance. The studies on measuring activity of work found out the time required for different steps of work for repairing the damage.

A Study on the Particle Size of Sand to Prevent Penetration of Subterranean Termite (Reticulitermes speratus kyushuensis) in Wooden Buildings

Termites cause massive damage to wooden architectural heritage structures. Chemical treatments have been commonly used to control them. In foreign countries, physical barriers made of sheet and particles impenetrable to termite are being used as an alternative to the chemical method. To study the efficacy of physical barriers, we investigated the appropriate sand particle size that can prevent the penetration of R. speratus kyushuensis. Upon evaluating the barrier properties of sand with particle sizes ranging from 0.85 to 4.00 mm, the penetration of termites was found to be effectively blocked at a particle size range of 1.00 to 2.80 mm. At smaller particle sizes, termites managed to move the sand particles and build an almost linear mud tube to penetrate the sand layer. At larger particle sizes, the termites could penetrate the sand layer by passing through the sand gaps.

Arboreal Crop Tree Termites in the Komkom Community Oyigbo Local Government Area in Port Harcourt, Nigeria

Termites cause major economic losses by destroying agricultural crop trees. This study aims to survey the arboreal crop tree termites in Komkom community of Oyigbo in the Niger Delta. The study area was divided into 10 zones and 306 trees were examined for the presence of termite nests, hollow sounds and mud tubes. Samples of termites with its nest, hollow, mud tube and tree cuttings were collected from infested trees using metal spatula, sorted and identified. Approximately 9.5% of the sampled trees had some termite presence as arboreal nests, hollowness or mud tubes. The trees most affected were Gmelina arborea (Gmelina), Dacryodes edulis (Native pear), Persea americana (Avocado), Citrus sinensis (Orange), Chrysophyllum albidum (African star apple), Cocos nucifera (Coconut), and Mangifera indica (Mango). The termites identified were Odontotermes oblongatus, Microcerotermes annandalei, Microtermes sp (new), Microcerotermes paracelebensis, Neotermes spp, Glyptotermes kachongensis and Microcerotermes crassus. Eight crop trees - Anacardium occidentale (Cashew), Moringa oleifera (Moringa), Annona muricata (Soursop), Theobroma cacao (Cocoa), Psidium guajava (Guava), Irvingia gabonensis (Bush mango), Syzygium samarangense (Java apple), and Elaeis guineensis (Oil Palm) had no termite infestation in the study area. The result obtained in this study indicates the termite species that are pests of crop trees in the area.

<p class="ZootaxaTitle"><strong>Novel symbiotic relationship between a spionid polychaete and <em>Lingula</em> (Brachiopoda: Lingulata: Lingulidae), with description of <em>Polydora lingulicola</em> sp. nov. (Annelida: Spionidae)</strong></p>

A new spionid species Polydora lingulicola sp. nov., a novel symbiont of Lingula anatina Lamarck, 1801 is described here based on materials collected from the Yatsushiro Sea and Ariake Sea, southern Japan. Polydora lingulicola sp. nov., morphologically closest to P. glycymerica Radashevsky, 1993 and P. vulgaris Mohammad, 1972, is distinct from latter two shell-boring species by its smaller size, long maximum caruncle length, non-boring lifestyle, presence of subspherical yellow chromatophores on chaetiger 5 (visible in living specimens), and larval morphology. The new species was observed to construct mud tubes on the surfaces of L. anatina shells, with the tube apertures located near the lateral inhalant pseudosiphon of the hosts, and utilizes the water currents created by the filter-feeding host for feeding suspended food particles. Polydora lingulicola sp. nov. represents the first polychaetous annelid reported to exhibit an obligate symbiotic relationship with a lingulid brachiopod. Epibiotic polychaetes previously reported as P. cornuta Bosc, 1802 to occur on L. anatina shells from Japan in 1902 may belong to P. lingulicola sp. nov. The possibility that the wild populations of P. lingulicola sp. nov. may be vulnerable to extinction because they only associate with L. anatina, wild populations of which are near threatened by habitat loss, coastal pollution, and fishing pressure.

Rapid Biodiversity Evaluation of the Arboreal Termites in Kano University of Science and Technology, Wudil, Nigeria

A rapid biodiversity evaluation of arboreal termite was carried out on the campus of Kano University of Science and Technology, Wudil. Three different trees which include Mangifera indica, Azadirachta indica and Khaya senegalensis were selected from three different sites (campus new site, premises of administrative offices and commercial area) on the campus and examined for termite activity, either arboreal nests or mud tubes which indicated infestation by the termites. Using a soft brush termite samples were collected into a labeled sampling bottle containing 10% formalin solution by cutting open the mud tubes and the nests with a forceps on the trees. A total of one hundred and twelve (112) individuals termites were samples were collected during the study belonging to five species: Coptotermes sp., Microtermes sp., Odontotermes sp., Amitermes sp. and Nutitermes sp. The Coptotermes sp. are the most abundant species both on the trees and the sites. Khaya senegalensis has the greatest diversity of the termite fauna as compared to other trees while campus new site (site A) also has greatest diversity. Coptotermes sp are insects of agricultural economic importance and feed on dead wood; therefore, they are insect pests of these trees and other building structures on the campus.

Rapid Biodiversity Evaluation of the Arboreal Termites in Kano University of Science and Technology, Wudil, Nigeria

A rapid biodiversity evaluation of arboreal termite was carried out on the campus of Kano University of Science and Technology, Wudil. Three different trees which include Mangifera indica, Azadirachta indica and Khaya senegalensis were selected from three different sites (campus new site, premises of administrative offices and commercial area) on the campus and examined for termite activity, either arboreal nests or mud tubes which indicated infestation by the termites. Using a soft brush termite samples were collected into a labeled sampling bottle containing 10% formalin solution by cutting open the mud tubes and the nests with a forceps on the trees. A total of one hundred and twelve (112) individuals termites were samples were collected during the study belonging to five species: Coptotermes sp., Microtermes sp., Odontotermes sp., Amitermes sp. and Nutitermes sp. The Coptotermes sp. are the most abundant species both on the trees and the sites. Khaya senegalensis has the greatest diversity of the termite fauna as compared to other trees while campus new site (site A) also has greatest diversity. Coptotermes sp are insects of agricultural economic importance and feed on dead wood; therefore, they are insect pests of these trees and other building structures on the campus.

Transgenerational Immune Priming in the Field: Maternal Environmental Experience Leads to Differential Immune Transfer to Oocytes in the Marine Annelid Hediste diversicolor.

Transgenerational immune priming (TGIP) is an intriguing form of parental care which leads to the plastic adjustment of the progeny’s immunity according to parental immune experience. Such parental effect has been described in several vertebrate and invertebrate taxa. However, very few empirical studies have been conducted from the field, with natural host-parasite systems and real ecological settings, especially in invertebrates. We investigated TGIP in wild populations of the marine annelid Hediste diversicolor. Females laid eggs in a mud tube and thus shared the local microbial threats with the first developmental stages, thus meeting expectations for the evolution of TGIP. We evidenced that a maternal bacterial challenge led to the higher antibacterial defense of the produced oocytes, with higher efficiency in the case of Gram-positive bacterial challenge, pointing out a prevalent role of these bacteria in the evolutionary history of TGIP in this species. Underlying mechanisms might involve the antimicrobial peptide hedistin that was detected in the cytoplasm of oocytes and whose mRNAs were selectively stored in higher quantity in mature oocytes, after a maternal immune challenge. Finally, maternal immune transfer was significantly inhibited in females living in polluted areas, suggesting associated costs and the possible trade-off with female’s protection.

A rapid survey of the arboreal termites in a university environment in Port Harcourt, Nigeria

BackgroundTermites inhabiting tree crops are pests which if neglected could result to agricultural loss. In a study to investigate the arboreal termites of planted trees in Rivers State University, 1050 trees were sampled between July and October 2017. The study area was categorised into 10 zones, and all trees were examined for the presence of nests and mud tubes. Samples of termites and tree cuttings were collected from infected trees for identification of termites and trees.ResultsApproximately 37.71% of the sampled trees had some termite infestation as arboreal nests or presence of mud tubes. The trees most affected were Mangifera indica, Elaeis guineensis (Arecaceae), Polyalthia longifolia (Annonaceae), Pentaclethra macrophylla, Eucalyptus sp., Terminalia sp. and Persea americana (Lauraceae). The termites identified were Amitermes sp., Nasutitermes havilandi, Odontotermes sp., Microcerotermes sp., Glyptotermes sp. and Globitermes sp. The termites did not show preference for particular trees (p < 0.05). There was a significant association between the termite species and the nest type (p < 0.05); the observed difference between the species and nest sets arose by chance; in other words, they were not randomly distributed with respect to nest type. Termite-resistant crop trees were Psidium guajava and Cocos nucifera. With more than one in three infestation rates, there is the need for termite management.ConclusionThis basic knowledge of the termite species and distribution is vital for effective control measure as it indicates that there is need for control and management. Suggested management would require treatment of infested trees and control measures of all trees in the study area except P. guajava and C. nucifera.

Studies on termite infestation of buildings in Ase, a rural community in the Niger Delta of Nigeria

BackgroundTermites (Order Isoptera) are eusocial insects that are of great benefit and economic importance to humans. Despite its benefits and economic attributes to humans, it accounts for serious damage on buildings in Nigeria especially in the rural areas. The aim of this study was to collect preliminary data on termite infestation of the buildings in Ase, a local community in the Niger Delta region of Nigeria. Data was collected by direct observation of termites on the buildings, and a structured questionnaire was presented to respondents in houses with visual signs of infestation. Samples of termites were collected from parts of the houses with mud tubes or nests.ResultsA total of 106 houses were inspected with 35.85% infested with termites. The termites found were two species of Amitermes, one of Microcerotermes, three of Nasutitermes, two of Neotermes, and one of Odontotermes. Most infested homes (71%) were graded as moderate, severely damaged, and collapsed revealing a major problem. Percentage infestation of wood services revealed door frames 62.5% and wall (mud tubes) 87.75%, floor 18.85%, logs outside the house 56.25%, windows and roof 43.75%, ceiling 18.75%, and bathroom, furniture, and kitchen 6.25%. Respondents were 30–90 years old and did not attribute mud tubes to termite infestation. Seventy-two percent of the buildings were less than 60 years, and preventive measures used by respondents were Solignum and used engine oil. Most of the buildings were severely infested, and a < 2-year-old house showed visible signs of slight termite infestation.ConclusionThis study clearly demonstrates the level of termite infestation in Ase and the need for better control measures and increased awareness for early detection.

Escaping and repairing behaviors of the termite Odontotermes formosanus (Blattodea: Termitidae) in response to disturbance.

The escaping behavior of termites has been documented under laboratory conditions; however, no study has been conducted in a field setting due to the difficulty of observing natural behaviors inside wood or structures (e.g., nests, tunnels, etc.). The black-winged termite, Odontotermes formosanus (Shiraki), is a subterranean macrotermitine species which builds extensive mud tubes on tree trunks. In the present study, 41 videos (totaling ∼2,700 min) were taken on 22 colonies/subcolonies of O. formosanus after their mud tubes were partially damaged by hand. In general, termites consistently demonstrated three phases of escape, including initiation (wandering near the mud-tube breach), individual escaping (single termites moving downward), and massive, unidirectional escaping flows (groups of termites moving downward). Downward moving and repairing were the dominant behavioral activities of individuals and were significantly more frequent than upward moving, turning/backward moving, or wandering. Interestingly, termites in escaping flows moved significantly faster than escaping individuals. Repairing behavior was observed shortly after the disturbance, and new mud tubes were preferentially constructed from the bottom up. When predators (i.e., ants) were present, however, termites stopped moving and quickly sealed the mud-tube openings by capping the broken ends. Our study provides an interesting example that documents an animal (besides humans) simultaneously carrying out pathway repairs and emergency evacuation without congestion.

Fipronil enhanced natural occurrence of Fusarium solani (Hypocreales: Nectriaceae) on building infesting termite Heterotermes indicola Wasmann (Blattodea: Rhinotermitidae)

Abstract The Southeast Asian subterranean termite, Heterotermes indicola Wasmann (Blattodea; Rhinotermitidae), is recognized as a building infesting lower termite species in urban environment. The extensive use of chemical termiticides against aerial mud tubes and underground nests of H. indicola beneath the buildings could not suppress its infestation; however, it enhanced the environmental contamination and insecticide resistance. In the present study, we tried to control termites using naturally occurring entomopathogenic fungi Fusarium solani (Mart.) Sacc., along with sublethal concentrations of termiticide fipronil in no-choice feeding pathogenecity bioassay for 20 days. Termite mortality after 20 days of continuous exposure to highest fungal treatment 1 × 109 conidia/mL was 10% exclusively, whereas 100% mortality was calculated just after 16 days of concurrently exposure to 5 ppm of fipronil and highest rate of fungus 1 × 109 conidia/mL. These results indicated that insecticidal stress declined the immune response of termites and reduced the repellency of termites against fungal conidia by breaching the primary defense mechanism (allogrooming). This co-application of F. solani at suitable sublethal concentrations of fipronil showed the promising potential against termites that may reduce the selection pressure of pesticides and resistance risk by targeted pests, but further investigations are necessary for developing field trials.

Fine structure of the tubes of Maldanidae (Annelida)

Many marine annelids are active tube builders. Several polychaete families make agglutinated tubes by fixing sediment particles with specific secretions from their epithelial glands. The fine structure of the tubes of six species of Maldanidae from five genera (Nicomache minor, N. lumbricalis, Maldane sarsi, Praxillella praetermissa, Axiothella catenata, Rhodine gracilior) was examined by scanning electron microscopy. These species exhibit different lifestyles. Nicomache minor and N. lumbricalis inhabit massive hard tubes attached to stones. Other species live in the sediment, Rhodine in rigid organic tubes, Praxillella, Axiothella and Maldane in sand or mud tubes. All the examined maldanid tubes have a similar basic structure. The inner sheath of the tubes is made of a hardened organic lining secreted by the worm. Fibres from the inner sheath fasten sediment particles of the agglutinated layer. In Nicomache the tube surface is covered with a fibrous outer layer. All tube layers contain variously arranged organic fibres, which form a 3D network in the agglutinated layer and fabric-like linings in the inner sheath and outer layer. The tubes of Maldanidae may be important for taxonomy, and useful for identification of fossils.

English

Termites are serious pests of agricultural crops and rural houses in Ethiopia. Some attempts were made to control termites on crops. However, termite problem on rural houses is a neglected area regardless of the intensity of the problem which at times results in total collapses of newly constructed houses. To collect preliminary information on status of termite infestation to rural houses, surveys were conducted in three districts of the Central Rift Valley of Ethiopia in 2012.&nbsp; Data were collected by direct observations and through semi-structured interviews. A total of 58 houses were inspected in the three districts of which 91% were termite infested at deferent levels. About 81% of the houses aged less than 10 years. Over half of the homeowners used pre-construction preventive measures such as plastic sheet cover and painting with used engine oil. Even though termite infestation was common and serious, only 35% of the homeowners took post construction preventive measures mainly because of lack of knowledge on the problem. The post construction termite control methods used in the study area were removing or scratching mud tubes from the infested parts and painting of the houses with used engine oil. There was no evidence of using synthetic chemicals for the management of termites on rural houses. The local government officials or Development Agents were not aware of termite problems in rural houses as the problem was only seen as a secondary problem. Termite samples were collected from houses, wooden fences and mounds built attached to the exterior walls of the houses. The collected termites were only from the genera Macrotermes and Odontotermes where about 79% was found to be from the former genus. This study explicitly indicated that termites have a great impact on local houses leading to frequent repairing and rebuilding. This damage will eventually lead to deforestation and environmental degradation in addition to its economic impact and spread of the termites. According to key informants of the study areas termite resistant tree species became rare and/or went extinct since they are used for all types of construction. In this study, preliminary information which can clearly demonstrate the level of termite infestation on local houses was obtained which can serve as an important input for the government both for awareness creation and developing best termite management practices. &nbsp; Key words: Macrotermes, Odontotermes, rural houses, survey, termites, termite control measures.

Predicting the predatory impacts of the “demon shrimp” Dikerogammarus haemobaphes, on native and previously introduced species

Biological invasions continue to exert pressure on ecosystems worldwide and we thus require methods that can help understand and predict the impacts of invasive species, on both native species and previously established invaders. Comparing laboratory derived functional responses among invasive and native predators has emerged as one such method, providing a robust proxy for field impacts. We used this method to examine the likely impacts of the Ponto–Caspian amphipod Dikerogammarus haemobaphes, known as the “demon shrimp”, a little investigated invader in European freshwaters that has recently established in the British Isles. We compared the functional responses on two prey species of D. haemobaphes with two other amphipod species: Dikerogammarus villosus, a congeneric invasive with well-documented impacts on macro-invertebrate communities and a native amphipod, Gammarus pulex. Prey species were native Chironomus sp. and the invasive Chelicorophium curvispinum, a tube-building amphipod also originating from the Ponto–Caspian region. D. villosus showed higher Type II functional responses towards both prey species than did D. haemobaphes and G. pulex, with the latter two predators exhibiting similar impacts on the native prey. However, D. haemobaphes had higher functional responses towards the invasive C. curvispinum than did G. pulex, both when prey individuals were tubeless and resident in their protective mud tubes. Thus, we demonstrate that functionally equivalent invasive congeners can show significantly different impacts on prey, regardless of shared evolutionary history. We also show that some predatory invaders can have impacts on native prey equivalent to native predator impacts, but that they can also exert significant impacts on previously introduced prey. We discuss the importance of invasion history and prey identity when attempting to understand and predict the impacts of new invaders.

The Water Sump Cleaning Machine by Vacuum Suction

This article describes a vacuum water sump cleaning machine which is used to clean up coal mine water sump. Cleaning machine is composed of mechanical structure and electrical control devices. The parts of machine are made up of Walk the flatbed, storage mud tank, vacuum pumps, suction pipe, mud tubes, swing devices, control valves, suction pipe and pressure tracheal. When working, under the function of vacuum pumping, cleaning machine pulls out the vacuum from storage mud tank through the vacuum air feeder. As the vacuum level in the tank is increasing, under the function of atmospheric pressure outside world, the mud flows into the reservoir along the suction tube. When storage mud tank is full, vacuum pump automatically shut down. Turning off the vacuum valve and opening the pressure valve, the slime in the tank under the function of compressed air comes into the mine car through the row mud tube. The layout of this cleaning machine is reasonable, what is more, it is flexible and convenient to operate, so that it reduces the labor intensity significantly and improves the work efficiency of the clearance.

Appraisal of the Economic Activities of Termites: A Review

Termites can be found through out the world largely in the tropical and sub-tropical countries. They are social insects, feeding on cellulosic materials and live in colonies. Termites comprise the Order Isoptera with six families, 170 genera and 2600 species, of which six species are present in Nigeria. The most striking aspects of termites is their destructive tendency. They feed on wood indiscriminately, and tend to destroy timber and other wooden materials of importance to man, and this brought them into direct competition with man. However, their beneficial aspect to man is very significant. In most countries, where termites exist in abundance they are edible. Their burrowing within the soil increases the rate of percolation of water into the soil, thereby promoting water absorbent of the soil. Their feeding habit includes decomposition of dead trees, and incorporation into the soil, mineral nutrients of these trees. Man in response to the destructive activities of termites, developed various controlled methods towards them, which include the use of pesticides such as DDT ( Dichloro Diphenyl Trichloroethane), BHC ( Benzene Hexachloride ), Aldrin, Dieldrin, soil barrier termiticides, treated zone termiticides, dust and fumigant, and, non chemical control methods such as mud tube removal, debris removal, pathogenic fungi, mechanical barriers, heat, high voltage electricity or electrocution and wood replacement. The control of termites however, does not seek to totally exterminate them, but to bring their activities to a manageable level. The objective of this paper is to appraise the economic activities of termites.

Effect of Fipronil on Subterranean Termite Colonies (Isoptera: Rhinotermitidae) in the Field

To assess possible colony-level effects of fipronil, a commonly used nonrepellent termiticide, we conducted a field study of eight houses in the Raleigh, NC, area with infestations of the eastern subterranean termite Reticulitermes flavipes (Kollar) (Isoptera: Rhinotermitidae). We installed an extensive grid of in-ground monitoring stations on each property (mean = 68.6 monitors per property) and collected samples from these stations as well as from mud tubes in the structure and wood debris in the yard for approximately 6 mo. We genotyped all samples by using microsatellite markers to identify the number and locations of colonies present on each property. Houses were treated with either a full treatment (n = 5) or exterior/localized interior treatment (n = 3). After treatment, the monitors were checked monthly for 3 mo and then quarterly for 3 yr to track the fate of colonies. Wood debris in natural areas was checked semiannually for 3 yr. All 11 of the treated colonies (those attacking structures) disappeared within 90 d of treatment and were not found again. These colonies were presumed to be eliminated. In contrast, 60% of untreated colonies (those located > 6 m from the foundation wall at the time of treatment) continued to persist throughout the study, as did 25% of the likely treated colonies (those occupying monitors 0.5 m from the foundation wall where the treatment was applied). Our results provide strong evidence for potent colony wide effects of fipronil on subterranean termites leading to colony suppression and likely colony elimination under field conditions.