Experimental evidence for male biased flight-to-light behavior in two moth species

Many studies report a greater abundance of male than female moths in light trap catches. The finding was interpreted as evidence for male-biased attraction to light, but alternatives could not be ruled out. For example, it is not known, how much the sex ratio in the catches deviates from the natural sex ratio. To overcome these limitations, we experimentally tested the flight-to-light behavior of two moth species, Yponomeuta cagnagella (Hübner) (Lepidoptera: Yponomeutidae) and Ligdia adustata (Denis and Schiffermüller) (Lepidoptera: Geometridae), under standardized conditions in an enclosed environment. In our test, we controlled the sex ratio, age, and population size. We recorded the moths caught in the trap and those that remained outside. Depending on the species, between 27 and 72% of all moths were caught in the light trap. We found that male moths were significantly and about 1.6 times more frequently attracted to the light than female moths. Our results were consistent for both species and hold good on the level of populations. We experimentally supported the general observation of a sexual dimorphism in the flight-to-light behavior of moths. Possible functional explanations include different flight activities of males and females or differences in the perception of light between males and females. Our experimental demonstration of a sexual dimorphism in the flight-to-light behavior of moths together with the common observation of an overrepresentation of males in light traps and other artificial light sources has implications for population and conservation biology.     

Evaluation of pheromone-baited traps for winter moth and Bruce spanworm (Lepidoptera: Geometridae)

We tested different pheromone-baited traps for surveying winter moth, Operophtera brumata (L.) (Lepidoptera: Geometridae), populations in eastern North America. We compared male catch at Pherocon 1C sticky traps with various large capacity traps and showed that Universal Moth traps with white bottoms caught more winter moths than any other trap type. We ran the experiment on Cape Cod, MA, where we caught only winter moth, and in western Massachusetts, where we caught only Bruce spanworm, Operophtera bruceata (Hulst) (Lepidoptera: Geometridae), a congener of winter moth native to North America that uses the same pheromone compound [(Z,Z,Z)-1,3,6,9-nonadecatetraene] and is difficult to distinguish from adult male winter moths. With Bruce spanworm, the Pherocon 1C sticky traps caught by far the most moths. We tested an isomer of the pheromone [(E,Z,Z)-1,3,6,9-nonadecatetraene] that previous work had suggested would inhibit captures of Bruce spanworm but not winter moths. We found that the different doses and placements of the isomer suppressed captures of both species to a similar degree. We are thus doubtful that we can use the isomer to trap winter moths without also catching Bruce spanworm. Pheromone-baited survey traps will catch both species.     

Assessing the value of the Garden Moth Scheme citizen science dataset: how does light trap type affect catch?

Done well, citizen science projects can gather datasets of a size and scope far larger than would be possible using professional researchers. This study uses data gathered in Britain by the Garden Moth Scheme (GMS). Participants run garden light traps for at least 26 weeks a year and complete garden questionnaires detailing garden habitat and nearby landscape features. We used data exploration and generalised linear modelling (GLM) to investigate whether the data can be used to generate reliable research findings, testing the effect of moth light trap type on moth catch. Robinson traps, then Skinner traps, then Heath traps were found to catch the highest abundance and diversity of moths. Mercury vapour bulbs, then blended light bulbs, then actinic bulbs collected the highest abundance and diversity of moths. The GMS dataset can be used to generate useful and reliable research findings, and can be used in the future to investigate temporal and spatial trends in moth assemblage. Under international law, the use of mercury vapour bulbs will be phased out in coming years, leading to changes in the way moth assemblages are sampled. Information on the relative efficacy of different bulb types will aid the analysis of long‐term moth datasets after these changes.     

Influence of within-orchard trap placement on catch of codling moth (Lepidoptera: Tortricidae) in sex pheromone-treated orchards

The influence of trap placement on catches of codling moth, Cydia pomonella L., was examined in a series of studies conducted in orchards treated with Isomate-C Plus sex pheromone dispensers. Mark-recapture tests with sterilized moths released along the interface of pairs of treated and untreated apple and pear plots found that significantly more male but not female moths were recaptured on interception traps placed in the treated plots. In a second test, significantly higher numbers of wild male and female moths were caught on interception traps placed in treated versus untreated plots within a heavily infested orchard. The highest numbers of male moths were caught on traps placed along the interior edge of the treated plots. Trap position had no influence on the captures of female moths. In a third test, north-south transects of sex pheromone-baited traps were placed through adjacent treated and untreated plots that received a uniform release of sterilized moths. Traps on the upwind edge of the treated plots caught similar numbers of moths as traps upwind from the treated plots. Moth catch was significantly reduced at all other locations inside versus outside of the treated plots, including traps placed on the downwind edge of the treated plot. In a fourth test, five apple orchards were monitored with groups of sex pheromone-baited traps placed either on the border or at three distances inside the orchards. The highest moth counts were in traps placed at the border, and the lowest moth counts were in traps placed 30 and 50 m from the border. In a fifth test, the proportion of traps failing to catch any moths despite the occurrence of local fruit injury was significantly higher in traps placed 50 versus 25 m from the border. The implications provided by these data for designing an effective monitoring program for codling moth in sex pheromone-treated orchards are discussed.     

Impact of trap design, windbreaks, and weather on captures of European corn borer (Lepidoptera: Crambidae) in pheromone-baited traps

Pheromone-baited traps are often used in ecological studies of the European corn borer, Ostrinia nubilalis (Hübner) (Lepidoptera: Crambidae). However, differences in trap captures may be confounded by trap design, trap location relative to a windbreak, and changes in local weather. The objectives of this experiment were, first, to examine differences in 0. nubilalis adult (moth) captures among the Intercept wing trap, the Intercept bucket/funnel UNI trap, and the Hartstack wire-mesh, 75-cm-diameter cone trap (large metal cone trap) as well as among three cone trap designs. Second, we examined the influence of the location of the large metal cone trap relative to a windbreak on the number of moths captured. Third, we examined the relationship between nightly mean air temperature, relative humidity, wind speed, precipitation, and the number of moths captured in large metal cone traps. The number of moths captured was significantly influenced by trap design, with large metal cone traps capturing the most moths. Wing and bucket traps were ineffective. Differences among trap captures were significant among trap locations relative to a windbreak. Under strong (>14 kph) or moderate (7 <14 kph) wind speeds, traps located leeward of the windbreak captured the most moths, but when wind speeds were light (<7 kph), traps not associated with windbreaks captured the most moths. The multiple regression model fitted to the relationship between number of moths captured per Julian date and nightly weather patterns was significant. Nightly mean air temperature was the most influential parameter in the model, and its relationship with moth capture was positive.     

Comparison of pheromone-mediated mating disruption and conventional insecticides for management of tufted apple bud moth (Lepidoptera: Tortricidae)

Large-plot studies were used to compare pheromone-mediated mating disruption and conventional insecticide applications for management of tufted apple bud moth, Platynota idaeusalis (Walker), in North Carolina in 1993 and 1994. Pheromone trap catches were reduced in mating disruption blocks, and traps placed in the lower stratum of the canopy had a higher level of trap capture reduction compared with traps placed in the upper stratum. First-generation tufted apple bud moth exposure to either pheromones for mating disruption or insecticides affected second generation pheromone trap catches in the lower and upper canopy. More second generation male moths were caught in pheromone traps placed in the upper compared with the lower canopy in blocks treated with pheromones for mating disruption during the first generation, whereas the opposite was true in blocks treated with insecticides during the first generation. Despite reduced trap catches in pheromone-treated blocks, egg mass densities were not reduced in these blocks compared with insecticide-treated blocks. Furthermore, fruit damage was not significantly different between mating disruption blocks and conventionally treated blocks in orchards with relatively low populations of tufted apple bud moth, but damage was greater in mating disruption blocks in orchards with higher moth densities.     

Pheromone‐trapping the nun moth,Lymantria monacha (Lepidoptera: Lymantriidae) in Inner Mongolia,China

The nun moth, Lymantria monacha L., is one of the most important defoliators of Eurasian coniferous forests. Outbreaks during 2011–2015 in the natural/planted larch, and larch‐birch mixed forests of the Greater Khingan Range in Inner Mongolia, China, caused tremendous timber losses from severe defoliation and tree mortality. A series of trapping experiments were conducted in these outbreak areas to evaluate the efficacy of a synthetic species‐specific pheromone lure based on the female pheromone blend of European nun moth populations. Our results clearly show that the nun moth in Inner Mongolia is highly and specifically attracted to this synthetic pheromone, with few gypsy moths (Lymantria dispar) captured. Flight activity monitoring of L. monacha male moths using pheromone‐baited Unitraps at 2 locations during the summer of 2015 indicated that the flight period started in mid‐July, peaking in early August at both locations. Based on male moth captures, there was a strong diurnal rhythm of flight activity throughout the entire scotophase, peaking between 22:00 and 24:00. Unitraps and wing traps had significantly and surprisingly higher catches than the gypsy moth traps. Unitraps fastened to tree trunks 2 m above ground caught significantly more male moths than those at the ground level or at 5 m height. Male L. monacha moths can be attracted to pheromone‐baited traps in open areas 150–200 m distant from the infested forest edge. Our data should allow improvement on the performance of pheromone‐baited traps for monitoring or mass‐trapping to combat outbreaks of this pest in northeastern China.     

Light trap transects – a field method for ascertaining the habitat preferences of night-flying Lepidoptera, using Mythimna turca (Linnaeus 1761) (Lepidoptera: Noctuidae) as an example

The habitat associations of the noctuid moth Double Line Mythimna turca (Linnaeus 1761) were studied in three areas in Britain by setting up light traps equidistant along transects which passed through different habitat types. Counts were made of M. turca at each trap station and the results compared with the habitat present in the vicinity of each trap. The results using chi-square analysis indicate that the preferred habitats for M. turca are woodland and Pteridium aquilinum scrub, especially where the grasses Agrostis capillaris and Holcus mollis occur. The environmental factors affecting moth catches are discussed and chi-squared expectations are adjusted to take account of the different efficiency of light traps in open grassland and woodland situations. The light trap transect method is shown to be useful for moth species where little is known of their ecology and can be used to provide a straightforward insight informing additional targeted autecological studies. The methodology may be less suited to those species which occur at low density, are poorly attracted to light or are known to migrate.     

All quiet on the western front? Using phenological inference to detect the presence of a latent gypsy moth invasion in Northern Minnesota

Following establishment in a new environment, invasive species expand their range through stratified diffusion, the coupling of local growth and spatial spread with long-distance movement of propagules that found new colonies. Consequently, the stages of arrival and establishment serially repeat until the entire habitat susceptible to invasion is occupied. An empirical example of such a phenomenon is the gypsy moth, Lymantria dispar (L.), invasion of northeastern Minnesota. Under a regional management program, a trapping grid is deployed along the L. dispar leading edge to detect male moth presence and inform management decisions. However, the presence of moths does not always indicate reproducing populations, and moths dispersing from populations behind the front can obscure the presence of latent invasions. We analyzed trapping data during the arrival and establishment of L. dispar in this region (2000–2012), supplemented with sentinel trap data to ascertain the timing of male moth flight (2005–2009), and derived yearly phenological predictions for male moth flight. We also used a male wing morphology metric (2007–2009) to further quantify spatial and temporal patterns associated with the L. dispar invasion. We provide evidence of an established L. dispar population when analyses suggest spatial randomness in trap catch data, and how the presence of phenologically distinct, immigrating adult moths from source populations outside of Minnesota recorded from sentinel traps could lead to the overestimation of the abundance of an established population. This work highlights the complexity of the initial invasion process even in a well-studied system for which a sensitive monitoring program exists.     

Large moths captures by a pest monitoring system depend on farmland heterogeneity

As intensive farmlands cover increasing areas of the world, associated biotic richness is crucial for the biodiversity of entire regions. Using data on non‐target Macrolepidopteran moths captured by a crop pest monitoring system, we compared local (100 m perimeter)‐ and landscape‐scale (1000 m perimeter) predictors of the numbers of moth individuals and moth species richness. During a single year (2009), eighteen light traps captured 91 726 individuals of 564 moths species. Typically for biotically impoverished habitats, the catches were dominated by a few superabundant species. Even in these impoverished assemblages, numbers of species increased with increasing herb and woody plants diversity (100 m around the traps), crop diversity (1000 m perimeter), landscape composition (1000 m) and configuration (100 and 1000 m). Abundance of the catches increased only with woody plants diversity in 100 m perimeters. In separate analyses of two species‐rich families, the presumably less mobile Geometridae increased with landscape configuration (i.e. density of edges) within 100 m perimeters around the traps, whereas the species richness of more mobile Noctuidae also reflected the landscape composition (i.e. proportional representation of land covers) at 100 m perimeters. Proportional representation of pest species decreased with increasing richness of herb and woody plants. Taken together, farmland heterogeneity increases moth species richness, whereas abundance of the catches mainly depends on local factors in the vicinity of light traps, and the local factors are more important for presumably less mobile Geometridae than for more mobile Noctuidae.     

Monitoring grape berry moth (Paralobesia viteana: Lepidoptera) in commercial vineyards using a host plant based synthetic lure

For some Lepidopteran pests, such as the grape berry moth Paralobesia viteana (Clemens), poor correlation between males captured in traps baited with sex pheromone and oviposition activities of female moths has called into question the value of pheromone-based monitoring for these species. As an alternative, we compared the capture of female and male grape berry moth in panel traps baited with synthetic host volatiles with captures of males in pheromone-baited wing traps over two growing seasons in two blocks of grapes in a commercial vineyard in central New York. Lures formulated in hexane to release either 7-component or 13-component host volatile blends captured significantly more male and female grape berry moth on panel traps compared with the numbers captured on panel traps with hexane-only lures. For both sexes over both years, the same or more moths were captured in panel traps along the forest edge compared with the vineyard edge early in the season but this pattern was reversed by mid-season. Male moths captured in pheromone-baited wing traps also displayed this temporal shift in location. There was a significant positive correlation between captured males and females on panel traps although not between females captured on panel traps and males captured in pheromone-baited traps for both years suggesting pheromone traps do not accurately reflect either female or male activity. Male moths captured in pheromone traps indicated a large peak early in each season corresponding to first flight followed by lower and variable numbers that did not clearly indicate second and third flights. Panel trap data, combining males and females, indicated three distinct flights, with some overlap between the second and third flights. Peak numbers of moths captured on panel traps matched well with predictions of a temperature-based phenology model, especially in 2008. Although effective, panel traps baited with synthetic host lures were time consuming to deploy and maintain and captured relatively few moths making them impractical, in the current design, for commercial purposes.     

Evaluating the phototactic behavior responses of the diamondback moth,Plutella xylostella,to some different wavelength LED lights in laboratory and field

Light traps equipped with light emitting diodes (LEDs) have been applied to manage some phototactic insect pests. The diamondback moth, Plutella xylostella, is a cosmopolitan insect pest to be seriously harmful to many cruciferous plants. The present research focused on evaluating the phototactic behavior responses of the moths to several wavelengths and photon flux densities of LED lights under laboratory and field conditions. The results from the laboratory showed that the highest phototactic behavior responses of P. xylostella moths were recorded for UV (380 nm) LED light under 1.5 µmol m⁻² s⁻¹ and 2.5 µmol m⁻² s⁻¹. The moths were more attracted to light traps equipped with 4 LEDs and 6 LEDs of 380 nm, respectively, between 20:00 and 22:00 than the other groups and night times in the field. The finding from the field was consistent with the results from the laboratory. We found that the 380 nm LED light results in the strongest attraction rate of the moths by 92.4 % and the moths caught in light trap with the UV LEDs was 1.62 times more than that with a black light. These data clearly demonstrate that P. xylostella moths have a high sensitivity to 380 nm, therefore, a 380 nm LED light trap could be useful for monitoring and controlling the moths.     

Long-term seasonal abundance patterns of Helicoverpa zea and Heliothis virescens (Lepidoptera: Noctuidae) in the Texas High Plains

Bollworm, Helicoverpa zea (Boddie), and tobacco budworm, Heliothis virescens (F.), male adult (moth) activities were monitored between 1982 and 1995 by using sex pheromone traps in the Texas High Plains. Moths were monitored weekly from early March to mid-November near Lubbock and Halfway, two prominent cotton production areas in the Texas High Plains region. Based on trap captures, the bollworm-budworm complex consisted of approximately 98% bollworms and approximately 2% tobacco budworms. Seasonal activity patterns varied between location for bollworm but not for tobacco budworm. The 14-yr average (+/- SE) bollworm moth abundance (moths per trap per week) at Lubbock was significantly higher (226.5 +/- 10.4) compared with that at Halfway (153.7 +/- 8.1). Correlation analyses showed a significant positive relationship between moth abundance and average weekly temperatures, whereas a significant negative relationship was observed between moth abundance and average weekly wind velocity for both species. Analyses also showed a positive correlation between moth abundance and cumulative degree-days (> 0.0 degrees C) from 1 January. A strong positive relationship was observed between moth abundance and weekly average precipitation for both species. Average weekly abundances were positively correlated between adjacent months during most of the active cotton fruiting season (June-September). However, the relationship between populations that contributed to the overwintering generation and the following spring populations varied between species and study sites. Nevertheless, data from this study indicated that late-season moth catches could be indicative of the dynamics of the early-season moth catches the following year in the High Plains. The mean population abundance curve based on 14-yr averages showed two bollworm population peaks at Lubbock, but only one peak at Halfway. Separate degree-day-based models were developed to describe long-term seasonal abundance patterns of bollworm moths for the Lubbock and Halfway sites.     

Landscape analysis of adult codling moth (Lepidoptera: Tortricidae) distribution and dispersal within typical agroecosystems dominated by apple production in central Chile

We analyzed the spatial distribution and dispersal of codling moth, Cydia pomonella (L.), adults within two heterogeneous agroecosystems typical of central Chile: commercial apple, Malus domestica Borkhausen, orchards surrounded by various unmanaged host plants. Both a geostatistical analysis of catches of adult males with a grid of sex pheromone-baited traps and an immunological self-marking technique combined with traps baited with a male and female attractant were used. The spatial analyses identified the key sources of moths within these diverse landscapes. Codling moth catches in traps were spatially associated within distances of ≈ 150-300 m. Similarly, the mean distance from the immunological self-marking plots within the commercial apple orchard to the traps that captured marked adults was 282 m. In contrast, the mean distance in the capture of marked moths from unmanaged self-marking plots to a commercial orchard was 828 m. These data suggest that the success of any future area-wide management programs for codling moth in Chilean pome fruit must include a component for managing or removing noncommercial hosts that surround orchards. This analysis also suggests that the selection pressure for resistance imposed by insecticide sprays within managed orchards is likely dampened by the influx of susceptible moths from unmanaged sites common in central Chile.     

Effect of weather factors on populations of Helicoverpa armigera moths at cotton-based agro-ecological sites

Pheromone trapping was used to monitor populations of the moth Helicoverpa armigera at five cotton‐based agro‐ecological sites – river, vegetable, orchard, forest and clean cultivation (areas under only cotton cultivation) – in the Bahawalpur district, Pakistan. Three locations at each site were chosen and three pheromone traps at each location were installed in cotton fields. Moth catches were recorded at 15–20 day intervals from 24 October 2004 to 19 December 2006. In 2004, the river sites showed the maximum trapped population of H. armigera (0.22/trap) followed by 0.165 per trap at the vegetable sites. Orchard, clean cultivation and forest sites had zero moth catches. In 2005, the river sites again showed the highest trapped population (0.57/trap), followed by clean cultivation (0.45/trap), vegetable (0.44/trap), orchard (0.40/trap) and forest (0.29/trap). The moths appeared during July to December and March to May. In 2006, sites showed non‐significant difference, with a population range of 0.47 to 0.97 moths per trap. On average, river sites peaked at 0.49 per trap, followed by vegetable (0.38), clean cultivation (0.47), orchard (0.35) and forest (0.25) sites. The peak was observed on 3 April 2006, and moths appeared during February to July and October to December. The minimum temperature in river, forest and clean cultivation sites; the maximum temperature in orchard sites; and the average temperature in river, orchard, forest and clean cultivation sites showed significant positive correlations with trapped moth populations. Relative humidity showed significant negative correlation with population at the orchard sites in 2005. All weather factors during 2004 and 2006 showed non‐significant correlations with the moth populations. No model was found to be best fit by multiple linear regression analysis; however, relative humidity, minimum temperature, maximum temperature, minimum temperature and maximum temperature contributed 8.40, 10.23, 2.43, 4.53 and 2.53% to the population fluctuation of the moth at river, vegetable, orchard, forest and clean cultivation sites, respectively.     

Comparison of mating disruption with pesticides for management of oriental fruit moth (Lepidoptera: Tortricidae) in North Carolina apple orchards

The efficacy of mating disruption by using Isomate-M 100 pheromone dispensers and two formulations of microencapsulated sprayable pheromone for management of oriental fruit moth, Grapholita molesta (Busck), was compared with conventional insecticides in large plot studies in Henderson County, North Carolina, in 2000 and 2001. In addition, experiments were conducted in small and large plots to test the response of oriental fruit moth males to different application rates of sprayable pheromone. Pheromone trap catches were significantly reduced in mating disruption blocks compared with conventional and abandoned orchards. Pheromone traps placed in the upper canopy captured significantly more moths than traps placed in the lower canopy across all treatments, and lures loaded with 100 microg of pheromone caught more moths than traps with 300 microg, but the difference between doses was statistically significant at only one location in 2001. Isomate-M 100 provided excellent trap shutdown and was significantly more effective than sprayable pheromone formulations. Fruit damage by oriental fruit moth larvae was very low (< or = 1%) in mating disruption blocks and was generally lower than in conventional and nonmanaged blocks. Based on male moth response to pheromone traps in small plots, there was little difference among doses of sprayable pheromone, ranging from 12.4 to 49.1 g (AI)/ha, but efficacy declined at 2.4 g (AI)/ha. With the exception of one orchard, there was no significant difference between 12.4 and 37.1 g (AI)/ha under low and high oriental fruit moth population pressure in large plot studies. Mating disruption proved to be an alternative to organophosphate insecticides for managing oriental fruit moth populations in North Carolina apple orchards.     

Spatial distribution,sampling efficiency and Taylor's power law

1. A relationship between sampling efficiency and Taylor's power law (TPL) is derived and illustrated with data from gypsy moth samples taken in Pennsylvania. 2. It is shown that attractant traps such as pheromone and light traps may exhibit density‐dependent sampling efficiency which can influence the parameters of TPL. 3. Comparison of the light trap and pheromone trap sample data with those of a standardised suction trap enables the attractant traps to be standardised. 4. Rescaling male moth catches per trap to number per unit volume increases the slope, intercept and correlation coefficient while stretching the pattern of data points. 5. Density‐dependent sampling efficiency of attractant traps shows how TPL is sensitive to spatial aggregation behaviour as well as other life‐history variables.     

Monitoring of the European corn borer (Lepidoptera: Crambidae) in central Maine

Pheromone trap types and within-field trap locations were compared for their effectiveness in monitoring the flight activity of European corn borer, Ostrinia nubilalis (Hübner), and its relationship to egg mass density and crop damage in sweet corn in central Maine from 1995 to 1996. The use of both 3:97 Z:E-11-tetradecenyl acetate and 97:3 Z:E-11 tetradecenyl acetate pheromone blends confirmed that European corn borer in central Maine is attracted to both pheromone lure types. European corn borer moths were captured predominantly with the E-lure type than with the Z-lure type in both years. The Scentry Heliothis trap was more effective than the Multi-Pher trap, but similar to the pheromone-baited water pan trap for monitoring European corn borer flights. With the Scentry Heliothis trap, the grassy border and 1st corn rows were the best locations for moth capture during the early flight period, but during the peak flight period, traps located in the middle of the field caught the most moths. Corn damage was recorded before moth captures in some sites and before egg mass counts in others, indicating poor efficacy of traps for early flights. Significant and positive correlations were found between moth captures in the midfield location and egg mass counts, and corn leaf damage, and between egg mass counts and corn leaf damage. However, low coefficients of variation suggest that pheromone trap captures were not good predictors of European corn borer leaf damage in sweet corn.     

Vertical distribution of codling moth adults in pheromone-treated and untreated plots

The vertical distribution of codling moth,Cydia pomonella (L.) within pheromone-treated and untreated apple and pear orchard canopies was determined using tethered virgin females, unbaited sticky traps, and blacklight observation of released moths. Mating of virgin females tethered at various heights in untreated orchard canopies increased with placement height from 1–4 m. Application of pheromone dispensers for mating disruption at 2 and 4 m above the ground greatly decreased mating. Greatest capture of males and females on unbaited sticky traps occurred at mid- and upper-canopy heights. Total capture of males and females in pheromone-treated plots was not statistically different than in untreated plots. The percentage of mated females captured on sticky traps did not vary with trap height or pheromone treatment. Released moths marked with flourescent powder and observed at dark with a blacklight indicated that moths are primarily distributed high in the canopy. However, males shifted to a position lower in the canopy when pheromone dispensers were placed 2.1 m above the ground. Results suggest that pheromone dispensers be placed in the upper canopy for optimal disruption of codling moth mating.     

Trap style influences wild pig behavior and trapping success

Despite the efforts of many natural resource professionals, wild pig (Sus scrofa) populations are expanding in many areas of the world. Although many creative techniques for controlling pig populations are being explored, trapping has been and still is the most commonly used method of population control for many public and private land managers. We conducted an observational study to examine the efficiency of 2 frequently used trap styles: a small, portable box-style trap and a larger, semi-permanent, corral-style trap. We used game cameras to examine patterns of trap entry by wild pigs around each style of trap, and we conducted a trapping session to compare trapping success between trap styles. Adult female and juvenile wild pigs entered both styles of trap more readily than did adult males, and adult males seemed particularly averse to entering box traps. Less than 10% of adult male visits to box traps resulted in entries, easily the least percentage of any class at any style of trap. Adult females entered corral traps approximately 2.2 times more often per visit than box traps and re-entered corral traps >2 times more frequently. Juveniles entered and re-entered both box and corral traps at similar rates. Overall (all-class) entry-per-visit rates at corral traps (0.71) were nearly double that of box traps (0.37). Subsequent trapping data supported these preliminary entry data; the capture rate for corral traps was >4 times that of box traps. Our data suggest that corral traps are temporally and economically superior to box traps with respect to efficiency; that is, corral traps effectively trap more pigs per trap night at a lower cost per pig than do box traps. © 2011 The Wildlife Society.