Trap Placement Research Articles

Using Room Temperature Current Noise To Characterize Single Molecular Spectra

We propose a way to use room temperature random telegraph noise to characterize single molecules adsorbed on a backgated silicon field-effect transistor. The overlap of molecule and silicon electronic wave functions generates a set of trap levels that impose their unique scattering signatures on the voltage-dependent current noise spectrum. Our results are based on numerical modeling of the current noise, obtained by coupling a density functional treatment of the trap placement within the silicon band gap, a quantum kinetic treatment of the output current, and a Monte Carlo evaluation of the trap occupancy under resonance. As an illustrative example, we show how we can extract molecule-specific "fingerprints" of four benzene-based molecules directly from a frequency-voltage colormap of the noise statistics. We argue that such a colormap carries detailed information about the trap dynamics at the Fermi energy, including the presence of correlated interactions, observed experimentally in backgated carbon nanotubes.

Light brown apple moth (Epiphyas postvittana) (Lepidoptera: Tortricidae) colonization of California

In response to the confirmed detection of the light brown apple moth, Epiphyas postvittana, in California, approximately 53,000 pheromone-baited Jackson traps were deployed and more than 246,000 males were caught (February 2007–February 2010). Approximately 46,000 manually entered catch records were corrected for errors and converted into catch per trap per day. As empty trap data (zeros) were not recorded, we added zeros between first and last catch for each trap based on the stated servicing period (~30,000), before analyzing for trends. Residual data error rate was estimated as 1.5 %. San Francisco and Santa Cruz counties had relatively high trap catches immediately upon trap set, and remained the leading population centers, while most other counties showed a more general trend of a slow build-up in catch over time (12 counties). An exponential increase in trap catch was observed in four counties with sufficient data. The pattern of spread indicated natural, as well as anthropogenic-assisted spread rates, with populations appearing well ahead of the invasion front. This jump dispersal is probably due to movement of host plants, unsurprising since eggs of this polyphagous moth are readily laid on foliage. There was evidence of seasonality in spread, probably linked to the phenology of the insect. There was a positive relationship between catch and known host tree preference, suggesting that trap placement in preferred hosts could add sensitivity to future surveys. Recommendations include the improved provision of data acquisition by telecommunications, standardization of data input, more archiving, and frequent analysis of trap catches. The rapid rate of population growth demonstrated in two counties and spread across many others supports the hypothesis of the recent arrival of E. postvittana in California.

Sand fly surveillance and control on Camp Ramadi, Iraq, as part of a leishmaniasis control program

Abstract : Vector-borne diseases are a serious health threat to U.S. troops stationed around the world. U.S. forces deployed to Iraq following the 2003 invasion experienced serious risk of infection by several vector-borne pathogens, specifically cutaneous (CL) and visceral leishmaniasis (VL) (Aliaga and Aronson 2007). Camp Ramadi, a U.S. military Forward Operating Base, was established in 2003 at the Al Anbar provincial capital of Ramadi, approximately 110 km west of Baghdad. In Iraq the total number of cases of CL reported per year from 2004 to 2008 was 1,655 and for VL was 1,711 (Alvar et al. 2012). In Al Anbar province in 2008, the estimated incidence of CL and VL was 1 per 10,000 (Alvar et al. 2012). Because of the war, the number of cases of both CL and VL was most likely underreported in Al Anbar and all provinces of Iraq (Alvar et al. 2012). Because of the risk of vector-borne diseases, each large U.S. military facility, such as Camp Ramadi, had a vector control program operating throughout the year. As part of a base-wide vector control program, unbaited Center for Disease Control and Prevention (CDC) light traps were placed at three locations on Camp Ramadi between April and August, 2009 to gather baseline population estimates of adult sand flies and monitor the success of subsequent control measures. This paper reports sand fly collections over the five-month period, whether they were positive for Leishmania, and describes efforts to control sand fly populations using ultra-low volume (ULV) insecticide applications. Three sites on Camp Ramadi were established for trap placement in areas where U.S. troops worked and lived. Site one was in a grove of palm trees near troop living quarters and the base medical clinic. Site two was in a plot of scrub vegetation near the helicopter landing pad, and site three in tall vegetation near buildings occupied by the base Commander. All three sites had active rodent burrows.

Effects of trap height on captures of arboreal insects in pine stands of northeastern United States of America

AbstractKnowledge of the effects of variables that can influence trapping results should help to optimise efforts in exotic species detection and other surveys. Two vertical trap placements (understorey, canopy) were tested to determine influence of these two heights on captures of Scolytinae (Coleoptera: Curculionidae), Cerambycidae (Coleoptera), and Siricidae (Hymenoptera) using semiochemical-baited multiple-funnel traps. Traps were baited with α-pinene, ethanol, ipsdienol, and ipsenol. A total of 8463 insects from 65 species and one genus were captured during the study. Average species richness, species diversity, abundance, number of unique species, and expected diversity were higher in understorey compared with canopy traps. Jaccard (0.94 ± 0.05) and Sørensen abundance (0.97 ± 0.03) similarity indices suggested highly similar communities sampled at the two trap heights.Dendroctonus valensLeConte,Dryocoetes autographusRatzeburg,Hylastes opacusErichson,Orthotomicus caelatus(Eichhoff),Gnathotrichus materiarius(Fitch),Asemum striatum(Linnaeus),Monochamus scutellatus scutellatus(Say),Rhagium inquisitor(Linnaeus), andXylotrechus sagitattus sagitattus(Germar) were more abundant in understorey traps. In contrast,Ips pini(Say),Pityogenes hopkinsiSwaine,Monochamus carolinensis(Olivier),Acmaeops proteus(Kirby), andAstylopsis sexgutatta(Say) were more abundant in canopy traps. The common practice of trapping in the understorey may be optimal for sampling arboreal insects as part of survey efforts. However, additional species may be found by trapping at other vertical placements.

Effect of habitat type and pitfall trap installation on captures of epigaeic arthropod assemblages in the boreal forest

AbstractIt is unrealistic to achieve high-resolution biodiversity inventories required to support local conservation strategies over large areas; however, benchmark associations between arthropods and ecosystem classification can support landscape scale biomonitoring. We investigated habitat associations of ground-dwelling spiders (Araneae), staphylinid beetles (Coleoptera: Staphylinidae), and carabid beetles (Coleoptera: Carabidae) in three forest ecosystems in northwestern Alberta, Canada and also studied the effect of variation in depth of pitfall trap installation on catch. Composition and diversity of all three taxa were correlated with the ecosystem classification map, and 20 species were strong indicators of particular habitats. The black spruce (Picea mariana(Miller) Britton, Sterns, and Poggenburg; Pinaceae) bog supported fewer species and individuals of beetles but this trend was not observed for spiders because of natural history traits associated with their performance in this environment. Pitfall trapping biases were constant among habitats enabling proper comparison of ground-dwelling invertebrate assemblages. Three species of beetles (Agonum retractumLeConte (Coleoptera: Carabidae),Pterostichus brevicornis(Kirby) (Coleoptera: Carabidae), andQuedius veloxSmetana (Coleoptera: Staphylinidae)) were disproportionally active beneath the soil surface, as catches were greater in pitfall traps with the lip situated 15–25 cm below the soil surface. Thus, even highly standardised trap placement will influence the concept of biodiversity achieved through pitfall trapping, because some target organisms are disproportionately active in subterranean zones.

Effects of Biogents Sentinel Trap Field Placement on Capture Rates of Adult Asian Tiger Mosquitoes, Aedes albopictus

The Biogents® Sentinel (BGS) trap is the standard tool to monitor adult Aedes (Stegomyia) albopictus (Skuse) (Diptera: Culicidae), the Asian tiger mosquito. BGS traps are commonly placed in residential properties during surveillance operations, but locations within properties may have significant differences in ambient light, temperature, and humidity (e.g. between a sunlit lawn and shady underbrush). We examined the effect of BGS trap placement on Ae. albopictus capture rates in three residential properties in Monmouth County, New Jersey, USA. In each property we visually selected locations as shade, partial shade, and sun. Traps in “partial shade” locations were under vegetation and were exposed to filtered sunlight during some parts of the day while “shaded” locations were never exposed to direct sunlight. Locations defined as “sun” were exposed to direct sunlight for large parts of the day. We placed a BGS trap in each of the three location types and used small data loggers to measure temperature, relative humidity, and light exposure at each trap during a 24-hour deployment. To address temporal variability, we made seven separate measurements from 31 August to 22 September 2010. We found that “partial shade” and “full shade” locations did not differ but that “full sun” locations had significantly higher light exposure, higher temperature, and lower humidity. Importantly, Ae. albopictus catches (males, females, or both) were consistently and significantly over 3 times higher in traps located in shaded locations. To further investigate the effects of local temperature and humidity on surveillance we examined Ae. albopictus collections from 37 BGS traps fitted with data loggers and deployed weekly from August through mid October, during the 2009 season, in three urban sites in Mercer County, NJ. We confirmed that local climate influences capture rates and that Ae. albopictus surveillance projects need to monitor trap placement carefully for maximum efficiency.

How varying pest and trap densities affect Tribolium castaneum capture in pheromone traps

AbstractThe red flour beetle, Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae), is an important insect pest in food processing facilities. Pheromone trapping is frequently used to monitor red flour beetle populations in structures; however, the optimal trap density and the relationship between trap captures and beetle density is not known. Two experiments were performed concurrently in environmentally controlled 30‐m2 walk‐in chambers to determine the relationship between aggregation pheromone trap captures of red flour beetles and beetle and trap number. In one experiment, beetle density was kept constant at 200 individuals per chamber while trap number was varied from 1 to 8, and in the other experiment trap number remained constant at one per chamber while beetle density varied from 20 to 800 individuals. Results indicated that approximately one out of 23 red flour beetles were captured in a trap. Number of beetles captured in traps increased significantly as beetle density increased; however, the proportion of beetles captured remained consistent across beetle densities with a mean of 4.7 ± 0.6% of individuals captured. Trap captures varied significantly with trap placement within experimental chambers, indicating that subtle differences in the trapping environment can influence trap captures. Data suggested that trap densities of 0.07–0.10 m−2 (2–3 traps per chamber) would maximize trap capture, whereas a trap density of 0.13 m−2 (four traps per chamber) would maximize the predictive ability of a trapping equation estimating beetle density from trap captures. Results provide information needed to more thoroughly explore how environmental factors might influence red flour beetle trap capture in the absence of changes in beetle density. Further understanding of these relationships will allow for more accurate assessments of absolute beetle density from pheromone trap capture data.

Field Trapping the Little Fire Ant,Wasmannia auropunctata

Two detection methods for the little fire ant, Wasmannia auropunctata (Roger) (Hymenoptera: Formicidae), both employing the pheromone attractant 2,5-dimethyl-3-(2-methylbutyl)pyrazine (2-MeBu-diMePy), were compared with peanut butter based detection, in order to evaluate differences in species specificity and detection reliability. Trapping was conducted using a transect through a macadamia orchard on the island of Hawaii. The transect consisted of a series of three-tree plots, each plot contained a peanut butter coated stick (the most common detection method used for W. auropunctata in Hawaii), a one—way trap treated with 2-MeBu-diMePy, and a piece of double-sided tape treated with 2-MeBu-diMePy. While there were no differences in the number of W. auropunctata counted with each detection method, and no differences in detection reliability (detecting the known presence of W. auropunctata in a plot), the pheromone—incorporating methods showed greater species specificity, retaining W. auropunctata almost exclusively. These results demonstrate the potential of pheromone—detection methods to selectively capture target ant species even when other ants are present and abundant. Combined data from all three detection methods and a previous visual survey along the transect showed a marked difference in the frequency of cohabitation among ant species. Of the 10 ant species collected, W. auropunctata was found as the sole ant species on a given tree at a significantly higher frequency than all other ant species except Pheidole fervens. 94% percent of the trees with W. auropunctata had only W. auropunctata, supporting previous observations that this species tends to displace other ant species. In addition, W. auropunctata microhabitat preferences were investigated using one—way traps containing 2-MeBu-diMePy, which were placed in three arboreal and three non—arboreal locations. While the number of ants captured did not differ by trap placement, when grouped, captures were significantly higher in arboreal than non-arboreal microhabitats.

A comparison of methods for estimating raccoon abundance: Implications for disease vaccination programs

AbstractAccurate estimates of demographic parameters are critical to the management of wildlife populations, including management programs focused on controlling the spread of zoonotic diseases. Rabies managers in the United States Department of Agriculture (USDA) have applied a simple raccoon (Procyon lotor) abundance index (RAI) based on cumulative catch of unique raccoons per unit area to determine vaccine‐bait distribution densities. This approach was designed to allow for both the collection of biological samples and to index raccoon abundance to determine bait densities for oral rabies programs. However, post‐baiting surveillance data indicate that, on average, only 30% of raccoons sampled have vaccine induced rabies antibody titers, suggesting that bait densities may not be well calibrated to raccoon densities. We trapped raccoons using both capture‐mark‐recapture (CMR) and the standard RAI to evaluate the accuracy of the current index‐based methodology for estimating raccoon density. We then developed a resource selection function from spatial data collected from radio‐collared raccoons to standardize trap placement within the existing RAI protocol, and evaluated the performance of this modified RAI approach relative to CMR for estimating raccoon population size. Both abundance and density estimates derived using the RAI consistently underestimated raccoon population sizes compared with CMR methods. Similarly, although the use of resource selection models to inform trap placement appeared to improve the accuracy of the RAI, the effectiveness of this method was inconsistent because of an inability to account for variance in detection probabilities. Despite the logistical advantages of using indices to estimate population parameters to determine vaccine bait distribution densities, our results suggest that adjustments may be necessary to more accurately quantify raccoon abundance, which should improve the effectiveness of rabies management in the United States. In particular, estimates of detection probabilities are needed to more precisely quantify abundance estimates and ensure appropriate vaccine coverage rates. © 2012 The Wildlife Society.

Effects of Trap Type, Placement and Ash Distribution on Emerald Ash Borer Captures in a Low Density Site

Effective methods for early detection of newly established, low density emerald ash borer (Agrilus planipennis Fairmaire) infestations are critically needed in North America. We assessed adult A. planipennis captures on four types of traps in a 16-ha site in central Michigan. The site was divided into 16 blocks, each comprised of four 50- by 50-m cells. Green ash trees (Fraxinus pennsylvanica Marshall) were inventoried by diameter class and ash phloem area was estimated for each cell. One trap type was randomly assigned to each cell in each block. Because initial sampling showed that A. planipennis density was extremely low, infested ash logs were introduced into the center of the site. In total, 87 beetles were captured during the summer. Purple double-decker traps baited with a blend of ash leaf volatiles, Manuka oil, and ethanol captured 65% of all A. planipennis beetles. Similarly baited, green double-decker traps captured 18% of the beetles, whereas sticky bands on girdled trees captured 11% of the beetles. Purple traps baited with Manuka oil and suspended in the canopies of live ash trees captured only 5% of the beetles. At least one beetle was captured on 81% of the purple double-decker traps, 56% of the green double-decker traps, 42% of sticky bands, and 25% of the canopy traps. Abundance of ash phloem near traps had no effect on captures and trap location and sun exposure had only weak effects on captures. Twelve girdled and 29 nongirdled trees were felled and sampled in winter. Current-year larvae were present in 100% of the girdled trees and 72% of the nongirdled trees, but larval density was five times higher on girdled than nongirdled trees.

Doryctinae (Hymenoptera: Braconidae) of Konza Prairie Excluding Species ofHeterospilusHaliday

The results of a survey of Doryctinae (Hymenoptera: Braconidae), excluding species of Heterospilus Haliday, 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 and canopy traps. Topographic trap placement included lowland, midslope, and upland areas. Twentyfour species were collected, including 18 in 2001 and 16 in 2005. Twenty-three of the 24 species were collected from the woodland/wetland sites, including 19 from gallery forest sites; five of the 24 species were collected from the prairie sites. Rhaconotus fasciatus (Ashmead) was the most abundant species in 2001 (n = 13); Callihormius bifasciatus (Ashmead) and Coiba jeffersoni Kula were the most abundant species in 2005 (n = 10). The following new species are described: Doryctes xanthogaster Kula and Marsh, Doryctes xanthosoma Kula and Marsh, Doryctinus zolnerowichi Kula and Marsh, and Pambolidea dollari Kula and Marsh. Glyptocolastes caryae (Ashmead), status revised is removed from synonymy with Glyptocolastes rugulosus (Cresson), the type species for Doryctinus Roman. The latter species is transferred to Acrophasmus Enderlein, resulting in Acrophasmus as a new synonym of Doryctinus. Synonymy of the aforementioned genera results in the following nomenclatural changes: Doryctinus amazonicus (Roman), new combination; Doryctinus arizonensis (Marsh), new combination; Doryctinus atriventris (Cresson), new combination; Doryctinus butleri (Marsh), new combination; Doryctinus costaricensis (Marsh), new combination; Doryctinus erugatus (Marsh), new combination; Doryctinus exilis (Enderlein), new combination; Doryctinus ferrugineus (Marsh), new combination; Doryctinus gauldi (Marsh), new combination; Doryctinus immigrans (Beardsley), new combination; Doryctinus maeandrius (Enderlein), new combination; Doryctinus marshi Greenbaum, revised combination; Doryctinus rubronotum (Marsh), new combination; Doryctinus rugulosus (Cresson), revised combination; Doryctinus scobiciae (Marsh), new combination; and Doryctinus secundus (Muesebeck and Walkley), new combination. Doryctes infuscus Marsh is a new synonym of Doryctes rufipes (Provancher), Pioscelus wichitus (Viereck) is a new synonym of Pioscelus borealis (Ashmead), and Rhaconotus graciliformis (Viereck) is a new synonym of R. fasciatus. The following species are first records for Kansas: C. bifasciatus, Dendrosoter sulcatus Muesebeck, D. rufipes, D. ferrugineus, Ecphylus hypothenemi Ashmead, Ecphylus rohweri Muesebeck, Ontsira mellipes (Ashmead), and Rhaconotus canadensis Marsh.

Estimation of population density of European pine marten in central Italy using camera trapping

Evaluating presence and abundance of small carnivores is essential for their conservation. In Italy, there is scarce information on European pine marten distribution, and no data are published on its abundance. Camera traps have been widely used to estimate population density applying capture–recapture models for species in which individual recognition is possible. Here we estimate the abundance of European pine martens in central Italy using camera trapping and a model that allows the estimation of population density without the need for individual recognition Rowcliffe et al. (Anim Conserv 11:185–186, 2008). Camera trapping was also used to evaluate habitat use patterns by martens. Fifteen camera traps were deployed in 90 placements for 15 days each, for a total of 1,334 camera days. Pine martens were captured in 24% of camera trap placements with a mean trap success rate of 0.33 photographs per camera placement. Estimated pine marten population density in the study area was 0.34 individuals km−2. Marten trap rate was not strongly associated with any habitat type, although there were trends towards lower probability of records at locations with high coverage of cultivated fields and higher probability of records at locations with high coverage of human-made woodland. The results suggest that pine martens in this area are not confined to wooded habitat. To our knowledge, this study is the first application of the Rowcliffe et al. (Anim Conserv 11:185–186, 2008) method to a wild carnivore population and, furthermore, the first estimation of population density of pine martens in Italy.

Capture of Two Moth Species in Traps Placed at Different Heights in Sex Pheromone Treated Apple Orchards

Studies were conducted to compare the effect of trap placement above and below sex pheromone mating disruption (MD) dispensers on captures of codling moth, Cydia pomonella (L.), and oriental fruit moth, Grapholita molesta (Busck), in apple orchards. Traps were placed at a height of 1.8 m or 4.5 m in the tree canopy whereas MD dispensers were placed at 3.1 m within the tree canopy; an adjacent set of plots were treated similarly with only insecticides (nonMD). All trees were approximately 4.8 - 5.1 m in height. Capture of codling moth adults in traps was highest in traps placed at 4.5 m in both MD and nonMD plots and lowest in traps placed at 1.8 m in MD treated plots. Reduction in adult codling moth capture was low to moderate (< 64%) in traps placed above dispensers and higher (>70%) in traps placed below dispensers over both years. Oriental fruit moth adult capture in 2007 was lowest in traps placed at 1.8 m in plots treated with MD. In 2008, capture of oriental fruit moth was highest in traps placed at 4.5 m.

The use of forest inventory data for placing flight-interception traps in the forest canopy

Forest canopies are an important part of forest ecosystems and comprise the majority of arthropod diversity. As tree crowns provide various microhabitats, a suitable trapping standard for canopy-dwelling arthropods is required. However, vertical trap position is often not standardized. We developed six vertical placement strategies for flight-interception traps based on information on tree height and crown base obtained from forest inventory data. Strategies differed in how crown base and height of trees were weighted in the calculations of trap height. Forest inventory data from almost 1600 plots in three regions of Germany. Were used to calculate the theoretical suitability of the strategies. The strategy to place traps at the canopy centre was predicted to result in very few trees for which placement would not be possible because trees are too short or crown base is too high, and this strategy by definition resulted in the lowest deviation of trap position from the canopy centre. The strategy Centre was tested in the field by installing three flight-interception traps each in 150 deciduous or coniferous stands of various age structures. On average, 53.8% of the traps were installed at exactly the desired height and for 86.9% of the traps the difference was <10% from the desired height. The strategy worked less well in thickets and pole woods. Overall, our results show that (1) forest inventory data are highly suitable to derive a priori trap placement strategies, even though these data are generally collected in only a small circle in each forest stand, (2) placing traps in the canopy centre largely avoids the problem of not being able to place traps at the desired height in the field, and (3) calculations of trap height should ideally be based on plot-specific data, but data from many stands of one forest type also provide a reasonable fit.

Effects of Habitat Type and Trap Placement on Captures of Bark (Coleoptera: Scolytidae) and Longhorned (Coleoptera: Cerambycidae) Beetles in Semiochemical-Baited Traps

Two studies were conducted to determine the effect of habitat selection and trap placement on catches of Scolytidae and Cerambycidae (Coleoptera) in northeastern U.S. forests. In a nonreplicated case study, four habitat types--closed canopy hardwood stand, closed canopy conifer stand, a low-intensity thinned Pinus strobus L. stand, and a high-intensity thinned P. strobus stand--were surveyed using alpha-pinene, ethanol, ipsenol, ipsdienol, and lanierone. Average trap catches, species richness, and the number of unique species captured were all highest in at least one of the thinned habitats. A second experiment that was replicated evaluated the placement of traps in relation to habitat patches. Semiochemical-baited traps (alpha-pinene and ethanol) were placed under a closed canopy forest, along an edge, and in a clearing and tested for effects on Scolytidae and Cerambycidae trap catches. Abundance and species richness were generally higher in the closed canopy and edge placements compared with traps in the open area. The highest number of unique species were captured in the edge and clearing.

Evaluation of a metofluthrin fan vaporizer device against phlebotomine sand flies (Diptera: Psychodidae) in a cutaneous leishmaniasis focus in the Judean Desert, Israel

The OFF! Clip-On fan vaporizer device releasing metofluthrin was evaluated against phletobomine sand flies in the Judean Desert, Israel, in October, 2009. A total of 76,400 sand flies was collected, with male flies representing 98.3%Phlebotomus sergenti and 1.7%P. papatasi. Females comprised 43.0% of the total catch and included 6.7% blood-fed females. Similar proportions of flies were collected in both suction and sticky traps. In trials with unbaited suction traps, similar numbers of sand flies were collected in traps with a metofluthrin device, blank device, or no device (i.e., suction only). In suction traps baited with CO(2) , higher numbers of P. sergenti males and blood-fed females were collected in traps with a blank device compared to traps with a metofluthrin device. In sticky traps baited with CO(2) , there were no significant differences between catches in traps with a metofluthrin device, blank device, or no device. The results suggest metofluthrin from the device is not repellent against sand flies in a field environment despite showing insecticidal activity against flies collected in suction traps.

An Aquatic Bal-Chatri for Trapping Snail Kites (Rostrhamus sociabilis)

The endangered Rostrhamus sociabilis plumbeus (Florida Snail Kite) has been the focus of several ecological studies emphasizing movements between and within wetland fragments. These studies have required the ability to trap and radiotag free-flying adults without significant risk of injury. We developed and tested a safe alternative to previous methods for trapping Snail Kites as part of a comparative study of VHF and satellite telemetry. The aquatic bal-chatri borrows from historical trap designs with modifications for trapping aquatic birds at the surface of the water. It consists of a square PVC frame with a series of parallel flourocarbon stringers and a mesh basket to restrain the lure species. Nooses are attached to the stringers and used to ensnare the toes of a predatory bird. The trap is held afloat by the PVC frame, with the mesh basket, stringers, and nooses positioned just beneath the surface of the water. After determining effective trap placement in relation to perched birds, we captured 11 kites in 13 days with native pomacea paludosa (Florida Apple Snail) and exotic Pomacea insularum (Island Apple Snail) as lures. Our results indicated that the aquatic bal-chatri can be used to target specific Snail Kites and recapture previously trapped individuals. This trap design is a safe, efficient, and low-cost alternative to methods previously used for capturing Snail Kites. Additionally, the aquatic bal-chatri is relatively easy to use and appears to have minimal impact on foraging behavior and breeding performance of Snail Kites.

Field optimization of the sex pheromone of Stenoma catenifer (Lepidoptera: Elachistidae): evaluation of lure types, trap height, male flight distances, and number of traps needed per avocado orchard for detection

The sex pheromone of Stenoma catenifer was evaluated in commercial avocado orchards in Guatemala to determine operational parameters, such as optimal lure type, trap height, trap density and estimates of the distances that male moths fly. Of four pheromone dispensers tested, gray and white rubber septa were of equal efficacy, whereas 1-ml low-density polyethylene vials and 2×3-cm polyethylene ziplock bags were least efficacious. The height at which wing traps were hung did not significantly affect the number of adult male S. catenifer captured. For monitoring S. catenifer, these data suggest that the pheromone should be dispensed from gray rubber septa in wing traps hung inside the tree canopy at 1.75 m, a height convenient for trap placement and monitoring. Mark-recapture studies of male S. catenifer indicated that, on average, males flew 67 m in one night. However, it is likely that this is an underestimate of the distance that male moths are capable of flying in a single night. Probabilistic modeling of S. catenifer capture data from different numbers of pheromone traps deployed in seven commercial avocado orchards of varying sizes and infestation levels suggested that 10-13 randomly deployed traps per orchard for a 7-day period are needed to detect at least one male S. catenifer with 90% confidence. These data provide sufficient information to develop effective protocols for using the S. catenifer pheromone to detect and monitor this pest in countries with endemic populations that are exporting fresh avocados, and for quarantine detection and incursion monitoring in countries receiving avocado imports from high risk areas.

Measuring adult insect emergence from streams: the influence of trap placement and a comparison with benthic sampling

Increased need to quantify adult insects emerging from streams as a part of foodweb and ecosystem studies has placed new demands on techniques used to sample adults. The population sampled must be better understood to establish the scope of inferences that may be drawn from emergence data. We used data from 2 different studies to compare the structure of insect assemblages represented by benthic samples and emergence-trap samples and to compare adult insect assemblages collected in emergence traps placed at mid-channel vs streambank locations. Nonmetric multidimensional scaling (NMDS) ordination showed that some components of the benthic assemblage were underrepresented in the emergence-trap samples and others were underrepresented in benthic samples. These differences were mainly caused by taxa that emerged by crawling out on the stream bank (e.g., Plecoptera) or whose larvae reside in habitats, such as stream margins, that are underrepresented with traditional benthic sampling (e.g., Dixidae). The flux of insects into traps placed mid-channel did not differ significantly from the flux into traps placed along the stream bank. Taxa collected by mid-channel and streambank traps overlapped considerably, but midchannel traps tended to collect proportionally more Trichoptera, Ephemeroptera, and Diptera, whereas streambank traps collected proportionally more Plecoptera. Our results can be used to improve trapping designs for future assessments of aquatic insect emergence in studies of insect behavior and life histories and as part of foodweb and ecosystem research.

Influence of Trap Position with respect to Height and Placement Surface on Capture of the Tobacco Moth, Ephestiaelutella (Hübner) (Lepidoptera: Pyralidae), in Pheromone Traps

Abstract The efficacy of pheromone traps is affected by trap placement and pest biology, as well as by the trap and lure design. We evaluated the effect of trap height and placement in relation to surfaces on tobacco moth catches using release-capture experiments. Six traps were mounted vertically in a 9 × 15 × 4.2-5.8 m shed on a wall at heights of 0, 1, 2, 3, 4 and 5 m. More catches were obtained near the ceiling and at 1 m above the floor in the dark. Catches at 1 m were negligible when light shone through the upper windows. In a 42.3 × 36.5 × 4 m tobacco warehouse, the respective efficacies of aerially suspended traps and surface-mounted traps were examined. The number of catches obtained using traps mounted on pillars was significantly higher than that obtained in traps suspended from poles. These results suggest practical considerations for monitoring in warehouses. We recommend eliminating any night lighting and placing traps on surfaces, such as walls and stored commodities, at higher positions that are within reach (1 m) to facilitate convenient inspection.