Canopy Trap Research Articles

The horseflies fauna diversity (Diptera: Tabanidae) in the habitats along the Mura river in Međimurje, Croatia

From May to September 2022, in the habitats along the Mura River, 1295 horseflies were sampled, classified into two subfamilies, six genera, and 21 species. Seven new records of horseflies were recorded for the first time in the researched area. Newly recorded species are: Tabanus bovinus, Tabanus cordiger, Tabanus sudeticus, Heptatoma pellucens, Haematopota italica, Haematopota scutellata, Haematopota subcylindrica. The species Haematopota pluvialis is the most abundant species, accounting for 60.07% of all sampled horseflies. Tabanus bromius followed with 21.23%, while the other 19 horseflies account for 18.7%. 18 species of horseflies belonged to the boreal-Eurasian type of fauna, two belonged to the Mediterranean type of fauna, i.e. the southern European subtype, while one species belonged to the Afro-Eurasian-arid type of fauna. In the collected sample of horseflies, 33 males classified into 10 species were recorded, while all other collected horseflies were females (1262 specimens) classified into 20 species. The greatest similarity of the horseflies fauna was recorded between the localities Križovec and Goričan, 81.81%. 17 species of horseflies were sampled with a modified Manitoba trap (the so-called canopy trap), and 14 species were sampled with an oil or liquid trap. The largest number of horsefly specimens (59.07%) was sampled in the month of July, while the least horseflies were sampled in September (0.15%). The most abundant species, Tabanus bromius and Haematopota pluvialis, recorded their highest peaks of abundance in July. The longest flight period lasting five months (from May to September) was recorded only for Haematopota pluvialis. Tabanus bromius was represented in all 11 localities, while the species Haematopota pluvialis was represented in 10 localities, as well as the species Chrysops viduatus. Based on the earlier research conducted in 2011 and current research of the horseflies fauna along the Mura river in Međimurje, 22 taxa of horseflies (21 species and 1 subspecies) classified into six genera were identified.

New record of Cepa apeca (Diptera, Syrphidae, Eristalinae, Merodontini) in the Andean-Amazonian region of Colombia and expansion of its geographic range

ABSTRACT Flower flies of the genus Cepa are endemic to the Neotropical region and Cepa apeca is currently known only from Costa Rica. Here we report the first record of C. apeca in Colombia based on a single female collected using a canopy trap in a dense secondary forest in a mountainous ecosystem in the locality of Vereda San Francisco, municipality of Florencia-Caquetá, at an altitude of 643 m.a.s.l. This finding constitutes the first record of the genus Cepa in Colombia and expands the geographic range of Cepa apeca by approximately 1,500 km (straight line) southwards to South America. Our finding represents the southernmost occurrence of the species and contributes to the incipient knowledge on the Diptera diversity in the Colombian Andean-Amazonian region.

Novel reusable canopy trap for sampling arboreal populations of electric ant, Wasmannia auropunctata (Hymenoptera: Formicidae)

AbstractHere we describe and test a novel canopy trap design for catching the little fire ant, Wasmannia auropunctata, known as the electric ant in Australia, as part of the National Electric Ant Eradication Program (the program) in North Queensland. As W. auropunctata is known to nest and forage both on the ground and in tree canopies, an effective arboreal trap to monitor their presence is a critical management tool. Our trap design addresses known issues with arboreal sampling such as sample retention, weather and debris proofing, robustness and canopy access. The trap is cost effective and friendlier to the environment compared with single‐use traps, due to its reusability and recyclable or biodegradable components. Field testing carried out in the Cairns region demonstrated that the canopy trap successfully collected ants with minimal non‐ant bycatch. In a known W. auropunctata‐infested area, the canopy trap recorded an 88% sensitivity rate and continues to be used as a surveillance tool within the program. Additional research is required to further evaluate the sensitivity of the canopy trap for monitoring W. auropunctata populations. We believe that the trap has potentially wider applications for arboreal arthropod sampling and can be modified to suit.

Efficiency of six different octenol-baited traps for collecting horseflies (Diptera: Tabanidae).

The efficiency and the potential species preference for six different horsefly trap types was studied. A total of 2401 horseflies were collected during this study. The most effective trap was the modified box trap with (27.9%), followed by the Nzi trap with (24.5%), Malaise trap (Townes design 1972) with (22.5)%, canopy trap with (17.9%), modified small canopy trap with (7.0%) and Malaise trap (Townes design 1962) with (0.2%). The Nzi and Malaise trap (Townes design 1972) did not differ significantly in the number of collected horseflies. The comparison of all other traps revealed significant differences in the number of collected horseflies. Tabanus bromius was the most abundant species with (58.6%) of the collected sample. The modified box trap was the most successful in collecting of T. bromius, while the Malaise trap (Townes design 1972) was the most successful in collecting the species Haematopota pluvialis, T. maculicornis and T. tergestinus. This study demonstrated that different trap designs influenced the quantity, species and taxonomic diversity of horseflies that were collected. Variables in the trap design included cloth type and colour and size and shape of trap. More detailed studies should be done to determine which factor or factors are most significant.

Semiochemical and Communication Ecology of the Emerald Ash Borer, Agrilus planipennis (Coleoptera: Buprestidae).

Knowledge of buprestid chemical ecology is sparse but the appearance of the invasive pest Agrilus planipennis Fairmaire in North America has provided the impetus to study in detail the semiochemistry and ecology of this important buprestid. The macrocyclic lactone (3Z)-12-dodecenolide [(3Z)-lactone] is identified as a key antennally-active compound that is produced by females and attracts males. Though a weak trap attractant alone, when combined with the host kairomone (3Z)-hexenol and the important visual cue of a green canopy trap, significant increases in male trap capture occur, thus defining (3Z)-lactone as both a sex pheromone of A. planipennis as well as the first and only known buprestid pheromone. The non-natural stereoisomer (3E)-12-dodecenolide and the saturated analog, 12-dodecanolide also exhibit mimetic activities towards male A. planipennis, suggesting a notable plasticity in this pheromonal structural motif. Efficient synthetic routes to these compounds have been developed. A series of fluoro-12-dodecanolides has also been synthesized containing CF2 groups as a strategy to bias the conformational space accessed by these macrolides and to assess if the analogs may act as mimetics for 12-dodecanolide pheromones associated in A. planipennis. These compounds also afford a unique opportunity to study the binding affinities of lactone surrogates with A. planipennis chemosensory proteins and olfactory receptors. Some progress has also been made in identifying the genes involved in the reception, processing and degradation of volatiles in this invasive insect. It is now evident that the behavior and ecology of A. planipennis involves a complex pattern of sensory modalities, including visual, tactile, olfactory and potentially acoustic components. Earlier reviews focused on studies of attractive host volatiles in development of a trapping system for early detection and visual and contact phenomena in A. planipennis mate finding. This review will update the semiochemistry and chemical ecology of A. planipennis and discuss studies on chemistry and behavior that have identified female-produced pheromone components and host kairomones.

Field studies of the efficacy of some commercially available essential oils against horse flies (Diptera: Tabanidae)

AbstractThe repellent activity of commercially available essential oils from the plants Cymbopogon winterianus, Mentha piperita, Litsea citrata and Lavandula angustifolia against female horse flies (Tabanidae) is not yet known, and it was studied in Eastern Croatia. In the absence of standard protocols for determining repellency in field studies, five canopy traps baited with 1-octen-3-ol were used, four of which were protected with essential oils. One canopy trap was always without any essential oil and used as negative control. The chi-square analyses of the trapping data for the canopy traps revealed that the essential oil of Lavandula angustifolia significantly reduced the number of collected horse flies in comparison to those collected in the canopy traps protected with the other essential oils. Significantly less specimens of Tabanus bromius were collected from the canopy traps protected with Lavandula angustifolia when compared with the traps protected with the other essential oils. However, the numbers of females of Tabanus tergestinus and Haematopota pluvialis collected from the canopy traps protected with all four essential oils did not differ significantly. A total of 93.6% of horse flies collected belonged to these three species. Tabanus bromius was the most abundant species with 76.5% in the samples collected by canopy traps. Finally, the traps protected with the essential oil of Lavandula angustifolia collected 0.50 times less horse flies than unprotected traps, whereas traps protected with oils of Mentha piperita, Cymbopogon winterianus, and Litsea citrata collected 0.19, 0.15 and 0.04 times less horse flies, respectively, than did unprotected traps.

Cardiochilinae and Ichneutinae (Hymenoptera: Braconidae) of Konza Prairie

Abstract. The results of a survey of Cardiochilinae and Ichneutinae (Hymenoptera: Braconidae) at Konza Prairie near Manhattan, Kansas are reported. Eleven sites representing prairie and woodland/wetland areas, including gallery forest, were sampled in 2001 and 2005 using Malaise traps and a canopy trap. Selected sites were also sampled haphazardly using pan traps and a sweep net. Six species of Cardiochilinae and two species of Ichneutinae were collected. Cardiochilines were collected at woodland/wetland sites only except a single specimen collected at a prairie site. Both species of Ichneutinae were collected at woodland/wetland sites and prairie sites. Cardiochiles floridanus (Ashmead) (n53) and Cardiochiles minutus (Cresson) (n54) were the most abundant species of Cardiochilinae in 2001 and 2005, respectively. Paroligoneurus newharti Kula, new species, the most abundant species of Ichneutinae in 2001 and only ichneutine collected in 2005, is described. Cardiochiles insculptus Mao and Cardiochiles minut...

Take-off time of the first generation of the overwintering small brown planthopper, Laodelphax striatellus in the temperate zone in East Asia.

Overseas migration of the small brown planthopper, Laodelphax striatellus (Fallén), occurs during the winter wheat harvest season in East Asia. Knowing the take-off time of emigrating L. striatellus is crucial for predicting such migrations with a simulation technique because winds, carriers of migratory insects, change continuously. Several methods were used in China and Japan from late May to early June 2012 and again in 2013 to identify the precise timing of take-off. These methods included: a tow net trap mounted to a pole at 10 m above the ground, a helicopter-towed net trap, and a canopy trap (which also had video monitoring) set over wheat plants. Laodelphax striatellus emigrated from wheat fields mainly in the early evening, before dusk. The insects also emigrated during the daytime but rarely emigrated at dawn, showing a pattern that is unlike the bimodal emigration at dusk and dawn of two other rice planthoppers, the brown planthopper, Nilaparvata lugens (Stål), and the white-backed planthopper, Sogatella furcifera (Horváth). There was no significant difference in the temporal pattern of take-off behavior between females and males of Japanese L. striatellus populations.

A horizontally polarizing liquid trap enhances the tabanid-capturing efficiency of the classic canopy trap

Host-seeking female tabanid flies, that need mammalian blood for the development of their eggs, can be captured by the classic canopy trap with an elevated shiny black sphere as a luring visual target. The design of more efficient tabanid traps is important for stock-breeders to control tabanids, since these blood-sucking insects can cause severe problems for livestock, especially for horse- and cattle-keepers: reduced meat/milk production in cattle farms, horses cannot be ridden, decreased quality of hides due to biting scars. We show here that male and female tabanids can be caught by a novel, weather-proof liquid-filled black tray laid on the ground, because the strongly and horizontally polarized light reflected from the black liquid surface attracts water-seeking polarotactic tabanids. We performed field experiments to reveal the ideal elevation of the liquid trap and to compare the tabanid-capturing efficiency of three different traps: (1) the classic canopy trap, (2) the new polarization liquid trap, and (3) the combination of the two traps. In field tests, we showed that the combined trap captures 2.4-8.2 times more tabanids than the canopy trap alone. The reason for the larger efficiency of the combined trap is that it captures simultaneously the host-seeking female and the water-seeking male and female tabanids. We suggest supplementing the traditional canopy trap with the new liquid trap in order to enhance the tabanid-capturing efficiency.

QUALITY IMPROVEMENT OF MANGOSTEEN FOR EXPORT THROUGH DRIP IRRIGATION SYSTEM AND YELLOW FLUORESCENT STICKY TRAP INSTALLATION

Mangosteen ( Garcinia mangostana Linn.) dubbed as “finest fruit of the world”, has potential for both domestic market and export. However, this potential is threatened by low fruit quality caused by production of yellow latex and fruit scarring. The research objective was to obtain technology to reduce yellow latex and control Scirtothrips dorsalis , a pest that causes scarring on mangosteen. A randomized block design with four treatments and 14 replications was used in this research. Significant differences among the treatments were calculated using the Honestly Significant Difference (HSD) test. The results showed that treatment of drip irrigation system in combination with removing weeds under the canopy (A) or removing weeds followed by minimum tillage under the canopy (B) or removing weeds then covering with rice hay mulch under the canopy (C), where N, P, K, Ca, Mg fertilizer and yellow fluorescent sticky trap were applied could reduce scarring intensity and percentage of yellow latex on the fruit peel. However, the treatments did not significantly impact fruit diameter or percentage of yellow latex inside the fruit. Nevertheless, treatment C improved mangosteen quality by as much as 67.79% fulfilling export standard requirements. Keywords: Mangosteen, quality improvement, drip irrigation, yellow fluorescent sticky trap

Tabanidae and other Diptera on Camel’s Hump Vermont: Ecological Observations

A canopy trap and aerial nets led to finding 8 species of Tabanidae. There was an abundance of calyptrate muscoid flies. Camel’s Hump is in the Green Mountains of western New England, USA. Discovering Diptera on Camel’s Hump involved sixteen visits over 40 years. Upwards of 23 other Diptera species are listed. Habitats on the east side and above 762 m (2500 ft) elevation on Camel’s Hump differ from the west slope but the boreal forest on both sides is influenced by cloud and fog precipitation on trees. The cliffs just above the 900 m level along the east side are often overlooked, are not seen from the summit and provide access to morning sun for insects. Recent visits explored the role of polarized skylight in relation to the canopy trap, the boreal forest environment and flies found there.

Comparison of the Efficiency of three types of Canopy Traps on the Collection of Horse flies (Diptera: Tabanidae)

Many different types of traps are used to monitor horse flies (Diptera: Tabanidae) throughout the world. Unfortunately, the hithertoo knowledge on the efficiency of traps is poor. Therefore, three new types of canopy traps have been evaluated, a standard trap and two modified ones, to determine their relative efficiency for collecting tabanids. Tabanids were collected with twelve traps at three different forest sites. One site was located in E' Croatia in the valley of the River Danube; two were located in the mountainous region of W' Croatia. The standard canopy traps collected significantly more tabanids than the smaller modified canopy traps. The size of the linen cover apparently influenced the collection efficiency. However, no significant effects were found between the modified high canopy traps. The highest efficiency of collections was recorded if the openings of the canopy traps were between 123 and 130 cm above ground. The standard canopy traps collected an average of 35 specimens per trapping period, whereas both modified high and small canopy traps collected 28 and 11 tabanids, respectively, per trapping period. The highest number of specimens and species was collected by the standard canopy traps. One may conclude that the designs of the three types of canopy traps affected the numbers of collected specimens and of species composition.

A comparison of trapping methods for Tabanidae (Diptera) in North Queensland, Australia

The ability to monitor the abundance and diversity of tabanid flies over wide areas requires effective and low-cost surveillance methods. Such monitoring activities help to quantify the risk of transmission of pathogens by tabanids. Here we examine the effectiveness and practicality of two types of trap (canopy traps and Nzi traps) and two types of attractant (octenol and carbon dioxide) for monitoring tabanid flies in tropical Australia. The Nzi trap consistently caught more tabanids and more species of tabanids than the canopy trap. It was also more robust and therefore required less maintenance in remote locations. The use of attractants substantially increased capture rates, both of individuals and species, and traps using both attractants were consistently the most effective. However, in remote locations, where it is not possible to check traps frequently, the use of attractants may not be feasible. When attractants were not used, the canopy trap caught very few tabanids, but the Nzi trap remained effective enough to be useful as a monitoring device. In addition, the number of tabanid species caught by the Nzi traps remained high, and included those that were most abundant. We therefore conclude that, in this region, Nzi traps are preferable for tabanid monitoring and that attractants greatly improve their effectiveness. However, for longterm monitoring, especially in remote locations, Nzi traps without attractants are a satisfactory option.

A Comparison of the Beetle (Coleoptera) Fauna Captured at Two Heights Above the Ground in a North American Temperate Deciduous Forest

We compared the beetle fauna captured in 12 pairs of flight intercept traps suspended at two different heights above the ground (≥15 m and 0.5 m) in a temperate deciduous forest in the southeastern United States to better understand how the abundance, species richness, diversity and composition of insect communities differ among forest strata. A total of 15,012 beetle specimens were collected representing 73 families and 558 morphospecies. Shannon's diversity and evenness were both higher near the ground than in the canopy, but no differences in total abundance or species richness between the two layers were observed. There were many differences at the family level, however, and species composition differed considerably between the two layers. About 29% and 31% of species were captured exclusively in the canopy or near the ground, respectively. The canopy traps were more similar to one another than they were to those near the ground and vice-versa based on both Sorensen's quotient of similarity and Raabe's percentage of similarity. The canopy and ground trap locations were quite distinct based on nonmetric multidimensional scaling. The degree to which species composition was similar (i.e., Sorensen's quotient of similarity) between pairs of traps decreased significantly with inter-trap distance for the traps in the canopy, but not for those near the ground, suggesting a more uniform community near the ground. Of the 41 families or subfamilies represented by more than 40 individuals, 12 were more abundant in the canopy and 14 were more abundant near the ground. Similarly, of the 16 families or subfamilies represented by more than 10 species, five were more species rich in the canopy and four were more species rich near the ground. Three families (Cerambycidae, Cleridae and Coccinellidae) were both more abundant and species rich in the canopy, whereas four other groups (Carabidae, Pselaphinae (Staphylinidae), Scolytinae (Curculionidae) and other Staphylinidae) were both more abundant and species rich near the ground. In addition to differing considerably among families, the vertical distribution patterns varied within many families as well. The distribution patterns for several groups are discussed in some detail with respect to known life history information.

A TWO-YEAR EVALUATION OF ELEVATED CANOPY TRAPPING FOR CULEX MOSQUITOES AND WEST NILE VIRUS IN AN OPERATIONAL SURVEILLANCE PROGRAM IN THE NORTHEASTERN UNITED STATES

The effectiveness of CO2-baited Centers for Disease Control and Prevention miniature light traps elevated in the tree canopy (approximately 7.6 m) was compared with light traps placed at ground level (approximately1.5 m) and grass-sod infused gravid traps for collecting Culex pipiens, Culex restuans, and Culex salinarius and detecting West Nile virus (WNV) activity in an operational surveillance program that encompassed 12 ecologically diverse sites in Connecticut in 2004 and 2005. More than twice as many Cx. pipiens were collected on average in light traps suspended in the tree canopy than in either light or gravid traps placed at ground level. This difference was generally restricted to those collection sites where markedly greater numbers of Cx. pipiens were collected with all trapping methods but was not associated with site-specific urbanization indices. Culex restuans was not preferentially attracted to light traps suspended in the tree canopy. No differences in the overall abundance of this species were recorded with either of the 2 trapping procedures, but both light traps were more effective than the gravid traps. Culex salinarius was significantly more attracted to ground-based light traps than traps suspended in the tree canopy, while gravid traps were ineffective at all sites regardless of the level of urbanization or any other specific land-use characteristic. CO2-baited light traps placed in the tree canopy were generally superior to ground-based light traps for detecting WNV in Cx. pipiens. West Nile virus-infected females were collected more regularly, and the frequency of infected pools was significantly greater. Twofold higher minimum field infection rates (maximum likelihood estimation [MLE] = 6.7 vs. 3.0 per 1,000 mosquitoes) were also recorded from canopy collections of this species, and virus was detected in canopy-collected females several weeks before it was detected in collections from light traps at ground level. We conclude that the use of CO2-baited light traps placed in the tree canopy for targeted trapping of Cx. pipiens and subsequent detection of WNV are likely to yield better overall results than light traps placed at ground level in this region of the northeastern United States. The virus isolation data obtained from Cx. pipiens collected in gravid traps compared favorably both temporally and spatially with results from canopy trap collections. There were no significant differences in the overall frequency of WNV-infected pools or MLEs for Cx. pipiens, but fewer total WNV isolations were made from Cx. pipiens collected in the gravid traps and virus was detected more infrequently. Results reaffirmed the utility of gravid traps as effective surveillance tools for detection of WNV in Cx. pipiens in the northeastern United States. However, findings also demonstrated that CO2-baited light traps placed in the tree canopy provided more consistent results where weekly detection of virus amplification is a critical objective. The comparative effectiveness of ground- and canopy-based light traps for detection of WNV-infected Cx. restuans and Cx. salinarius was inconclusive owing to the limited number of virus isolations that were made from these species during the 2 years of study. However, WNV virus isolations were made several weeks earlier and more frequently from Cx. restuans collected in traps placed in the canopy rather than at ground level in 2004. Results support the view that ground-based light traps are more effective for detection of WNV in Cx. salinarius.

Phenology and nest site preferences of wood-nesting bees in a Neotropical lowland rain forest

During a two year trap nest study in the forest reserve of the La Selva Biological Station, a total of 450 males, 288 females, and 455 nests from 16 species of solitary bees were collected. Trap nests were set up in six dead and six live trees, at canopy level and at 1.5 m height. Comparison of the phenology among species indicated a general seasonality pattern across two bee families, with peak abundance of nests and adults between May and August and lowest values between December and February. Contrary to an original hypothesis, adult and nest abundance was never negatively correlated with monthly rainfall. The occurrence of maximum values for males, females, or nests coincided with flowering peaks of trees at La Selva found in another study. The more sun-exposed canopy trap nests in dead trees were preferred by most species, but not Centris labrosa, which is assumed to be a rainforest specialist. According to this result, the protection of dead but standing canopy emergent trees for bee conservation in commercially managed forests is emphasized. Egg to adult development periods indicated that multiple generations per year might be common for the species investigated in this study.

MAMMALS OF THE RIO JURUÁ AND THE EVOLUTIONARY AND ECOLOGICAL DIVERSIFICATION OF AMAZONIA

We describe the nonvolant mammal fauna of the Rio Juruá of the western Amazon of Brazil, based on collections made during a year-long survey of the river. We, along with our colleagues Drs. Claude Gascon and Carlos Peres, designed the field project to examine the effects of the river on the differentiation among terrestrial vertebrates (mammals, birds, and amphibians and reptiles) at both the community and population levels. This monograph examines only the patterns of geographic variation and community structure of the small-bodied mammals. Species inventories were made at 16 primary trapping localities divided into eight pairs of cross-river sites, with two pairs in each of four regions from near the mouth to the headwaters of the Rio Juruá. A total of 81 species of nonvolant mammals were obtained, including nine new to science. Four of these are described herein; the others have been described elsewhere. We used a standardized trapping protocol to assess community structure at each of the 16 localities that included terrestrial and canopy trap stations in floodplain (várzea) and upland (terra firme) forest formations. Supplemental trapping was done in secondary habitats at all sites. We describe these sites, the trap effort expended, and the placement of trap stations relative to local habitats. We also describe each species of marsupial, sciurid rodent, murid rodent, and echimyid rodent encountered; comment on their systematics; and summarize aspects of habitat use, life history, geographic distribution, and geographic differentiation based on morphological and molecular traits. We examine patterns of differentiation in the mitochondrial cytochrome-b gene for samples of 41 of the 45 species of marsupials and rodents obtained within the Rio Juruá Basin, and discuss these patterns from the perspective of the entire Amazon and, in some cases, the Mata Atlântica of coastal Brazil. We also examine patterns of community organization within the Rio Juruá basin and throughout Amazonia, drawing attention to the geographic distribution of what appear to be major faunal units that are independent of habitat differences. Finally, we use principles of phylogeography to analyze patterns of geographic differentiation among the nonvolant mammals with regard to the Riverine Barrier Hypothesis. We show that, while there are few examples of taxa for which the Rio Juruá is apparently a barrier, most taxa either are largely undifferentiated throughout the basin or are sharply divided into reciprocally monophyletic mtDNA haplotype clades separable into upriver and downriver units. We argue that the concordance in the geographic placement of clade boundaries suggests a common history; moreover, both the age of these clades and their geographic position in relation to underlying geological features suggest that landform evolution has been an important, but underappreciated component of diversification within western Amazonia.

Responses of horse flies (Diptera: Tabanidae) to Jersey bullocks and canopy traps baited with ammonia, octenol, and carbon dioxide.

The attraction of females of six species of tabanids to stanchioned Jersey bullocks, unbaited canopy traps, and canopy traps baited with either octenol (1-octen-3-ol), ammonia (NH4OH), a combination of ammonia and octenol, or 5 kg of dry ice (CO2) was studied. A randomized Latin square design (treatments x sites x days) was used. Species diversity and number of flies captured in canopy traps unbaited or baited with octenol, ammonia, or the combination of octenol and ammonia did not differ significantly. Females of Tabanus americanus Forster, T. fuscicostatus Hine, and T. lineola F. were captured more frequently in CO2-baited canopy traps than on Jersey bullocks, but the reverse was observed for females of Leucotabanus annulatus (Say). The number of females of T. pallidescens Philip and T. wilsoni Pechuman collected from CO2-baited canopy traps and bullocks did not differ significantly.

Seasonal Abundance and Spatial Distribution Patterns of Three Adult Muscoid (Diptera: Muscidae) Species on Equine Premises

Adult face fly, Musca autumnalis De Geer, stable fly, Stomoxys calcitrans (L.), and horn fly, Haematobia irritans (L.), populations on four Kentucky horse farms were monitored weekly from late April to mid-October 1987 and 1988 using dry ice-baited canopy traps and visual counts of flies on pastured horses. Face flies were most abundant during May 1987 and June of both years followed by peak stable fly activity during mid-June, July, and August of both years and peak horn fly activity during mid-September of both years. Canopy trap collections of face flies were correlated with visual counts of face flies on pastured horses for 1987 and 1988. Horn flies were not collected in the canopy traps, and stable flies were not observed on pastured horses. Using visual count data to determine the degree of population aggregation, horn fly populations were found to be more contagious than face flies as populations increased on pastured horses. From the canopy trap data, face fly and stable fly populations had similar aggregation indices or similar distribution patterns as populations increased.

L-Octen-3-ol, an Effective Attractant for Tabanidae (Diptera)

The effectiveness of the canopy trap for female Tabanidae was increased significantly when l-octen-3-ol was used as an attractant. There was a threefold increase in the number of tabanids captured by traps with octenol (12.8 ± 2.1 females/trap) versus unbaited traps (3.7 ± 1.2 females/trap), and with dry ice plus octenol (72.1 ± 9.7 females/trap) versus traps with dry ice alone (24.7 ± 2.6 females/trap). There was also a significant increase in number of species in collections from traps with dry ice plus octenol (9.8 ± 0.9 species/trap) versus traps with dry ice alone (6.2 ± 0.9 species/trap). Tabanus molestus Say constituted 70% of the 1,038 tabanids collected.