首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
ABSTRACT.
  • 1 A total of 7063 specimens of Sphaeroceridae representing forty species were caught in four light traps, two in woodland and two in the open, at Rothamsted Experimental Station between December 1980 and December 1983.
  • 2 A complete list of species and the numbers of individuals of each is provided.
  • 3 The catches in the two traps in woodland were less diverse than the catches in the two traps in the open.
  • 4 Two-way analysis of variance demonstrated a significant difference in catch from trap to trap.
  • 5 When their similarities were compared, the four light trap catches formed two groups, corresponding with habitat type.
  • 6 The majority of the catch were Copromyza similis (Collin) (5555 specimens or 78.64% of the total). The species was most abundant in winter from mid-December to early February, although there were slight differences in times of maximum abundance between open and woodland habitats.
  相似文献   

2.
3.
4.
  • 1 Heath and Rothamsted light traps and a Johnson-Taylor suction trap were used to sample flying insects on Aldabra Atoll.
  • 2 The present study extended over two wet seasons. The pattern of relative monthly insect activity resembled the rainfall pattern. Catches were greatest during the months when there was a sudden marked increase in precipitation.
  • 3 Lepidoptera dominated light trap catches and Diptera suction trap catches, the total monthly insect numbers therefore reflecting the abundance of these two orders. Hemiptera, Coleoptera and Hymenoptera were also common.
  • 4 Predominant families were represented by only a few or even only one dominant species. These species were present throughout the study period although their monthly totals varied considerably, different species dominating the catches during different months.
  • 5 The composition and size of catches in the three light traps was affected by the type of light source and surrounding vegetation.
  • 6 A comprehensive list of families and selected common species is given with their relative monthly abundance in the light traps.
  • 7 Suction trap catches were segregated on an hourly basis to give a broad indication of insect flight periodicity.
  相似文献   

5.
  1. Adult emerald ash borers are attracted to green prism traps baited with the ash host volatile (3Z)-hexenol and the sex pheromone of emerald ash borer (3Z)-dodecen-12-olide [(3Z)-lactone]. Quantifying the heretofore unknown range of attraction of such traps would help optimize deployment strategies for early detection.
  2. Examining trap captures of traps deployed in pairs at variable distances offers insight into the range of attraction. Recent work has shown the range of attraction can be estimated as half the intertrap distance at which trap catch begins to decrease, which should occur when proximate traps overlap their respective attractive ranges.
  3. We estimated these traps' attractive range for emerald ash borer using 98 baited dark green prism traps deployed in pairs, one trap per tree, in an urban park in Saint Paul, Minnesota, USA in summer 2020.
  4. We estimate attractive range by fitting a logistic model to trap catch data using Bayesian inferential methods and describe advantages thereof.
  5. The attractive range of these baited traps was estimated to be between 16 and 73 m, with a median of 28 m. We recommend that dark green prism traps baited with these semiochemicals be placed 25–35 m apart near high-risk entry points.
  相似文献   

6.
7.
  • 1 The development of integrated pest management strategies requires that the semi‐natural habitats scattered across the landscape are taken into account. Particular determinants of insect pest abundance in overwintering habitats just before they migrate onto crops appear to be poorly known and of crucial importance for understanding patterns of crop colonization and pest population dynamics at the landscape scale.
  • 2 The emergence of pollen beetle Meligethes aeneus F. was studied in grassland, woodland edge and woodland interior over a 3‐year survey in France using macro‐emergence traps. A suite of variables at the local and the landscape scale was assessed for each trap, aiming to identify potential relevant habitat indicators. The effects of habitat characteristics were evaluated using partial least square regressions.
  • 3 It was found that M. aeneus can overwinter in all types of habitat but that particular habitat characteristics at the local and landscape scales may explain their abundance in overwintering sites more than the types of habitat: relative altitude, litter thickness, soil moisture and proximity to the previous year's oilseed rape fields appear to be positively correlated with abundance of adults over the 3 years.
  • 4 Hence, the abundance of emerged pollen beetles depends on both the landscape configuration of the previous year's oilseed rape fields around overwintering sites and local habitat characteristics. Landscape configuration may determine population flow towards overwintering sites in the late summer, and local habitat characteristics may influence survival rates during the winter. The findings of the present study provide valuable insight into the role of semi‐natural habitats as a source of pests, patterns of crop colonization in the spring, and the influence of landscape on pollen beetle abundance.
  相似文献   

8.
Abstract
  • 1 During 1989–93, field studies were conducted in Finland to develop a method based on pheromone traps to monitor and forecast population levels of the European pine sawfly (Neodiprion sertifer Geoffr.) and tree defoliation.
  • 2 Three traps per site were baited with 100 µg of the N. sertifer sex pheromone, the acetate ester of (2S,3S,7S)‐3,7‐dimethyl‐2‐pentadecanol (diprionol), in maturing pine stands in southern and central Finland. In addition, three different dosages (1, 10 and 100 µg) of the pheromone were tested in 1991–92.
  • 3 The highest number of males was observed in traps baited with the highest dose. On average, there was a 10‐fold increase in trap catch between lure doses.
  • 4 Density of overwintering eggs was used to evaluate the effectiveness of pheromone traps in predicting sawfly populations. The proportion of healthy overwintering eggs was determined each year. A model based on the number of current shoots on sample trees, diameter at breast height and tree height was formulated to estimate eggs per hectare.
  • 5 Linear regression analysis produced high coefficients of determination between number of males in traps and density of total eggs in the subsequent generation, when populations were at peak densities. The relationships were not significant for low population densities. The results indicate a risk of moderate defoliation when the seasonal trap catch is 800–1000 males per trap or higher.
  相似文献   

9.
10.
11.
12.
13.
14.
15.
16.
The Rothamsted Insect Survey has operated a Great Britain-wide network of light-traps since 1968. From these data we estimated the first ever national abundance indices and 35-year population trends for 338 species of common macro-moths. Although the number of trap sites which run each year is not constant, there is a representative, well-distributed core of traps that have run for 15 years. The proportion of operating sites catching a species and the annual geometric mean catch of successful traps were used to provide estimates of species range and absolute abundance. T, an index of long-term population trends, was used to compare trends among species. T was not biased by trap site turnover. The percentage of species displaying significant decreases (54%) was more than double that displaying increases (22%). Species found throughout Great Britain are decreasing most rapidly in the south and especially the southeast but species with a southerly distribution are increasing. Results of a preliminary overview suggest habitat and climate change may both play a role in changing species dynamics. The existence of estimates of abundances and trends for such a large species pool opens the way for much further research, linking trends with land-use changes, climate change and inter-specific dynamics.  相似文献   

17.
  • 1 Catches of male pea moths in six designs of trap, each containing (E,E)-8,10-dodecadienyl acetate as an attractant, were compared; triangular-shaped traps caught most moths.
  • 2 The vertical distribution of moths within a pea crop and the size of catches at different levels varied in different wind speeds. Three-quarter crop height is probably the optimum height for monitoring.
  • 3 Five trap designs (including the triangular type) captured only 20–30% of individuals landing on them; water traps were slightly more efficient.
  • 4 There was an eight-fold range in the number of moths caught depending on the sticky material used. ‘Bird-Tanglefoot’ was most effective.
  • 5 Smoke plumes, emitted from different trap designs in the field to simulate plumes of attractant, were photographed and measured. The effect of trap design on plume shape was confirmed in wind tunnel tests.
  • 6 Field tests showed that the more elongated the mean plume emitted from a trap the greater the catch.
  • 7 The tracks of individual moths flying to traps are discussed in relation to current views on orientation to odour sources.
  相似文献   

18.
1 The production of new insect pheromones for pest monitoring proceeds at a greater rate than their evaluation, with the consequential possibility of premature introduction. Fundamental to their successful deployment is the determination of a consistent relationship between adult male pheromone trap catches and pest damage. In the present study, adult pheromone traps and larval bait traps were used to examine spatial relationships between two species of Agriotes beetle and wireworms at the field scale. 2 The spatial distributions of adult male Agriotes lineatus and Agriotes obscurus in two fields were determined and compared with the distribution of their larvae. Data were assembled as spatially referenced trap counts, and analysed for evidence of aggregation and clustering using Spatial Analysis by Distance IndicEs (SADIE) methodology. Spatial stabilities of adult populations between sampling dates were tested using association tests. Spatial and quantitative linkages between adult and larval trap catches were also tested. Moreover, a new way of adapting SADIE methodologies is presented for situations where two datasets within an area do not share the same sampling points. 3 There was no significant difference in variance : mean relationships for the two species but there were differences in their spatial distributions, and this is a definitive example of the general argument stating that it is important to consider spatial as well as count data in ecological studies. The spatial distribution of A. lineatus varied between sampling occasions at both sites whereas A. obscurus had consistently significant SADIE indices over time at one site, and adult catches could also be linked to larval distributions and counts. It is proposed that observed differences between the two species can be explained by interference between traps and dissimilar movement rates. There was some evidence of an edge effect at the field boundaries. 4 The distance between pheromone traps is related to the time that elapses before adjacent traps interfere with trap captures and this limits the detection of statistically significant spatial patterns. It is shown that the current practice of adding trap counts for different Agriotes species and treating them as numerically equivalent is insufficiently robust to be recommended at this stage. 5 The implications for the use of sex pheromone traps in wireworm pest management are considered. It is concluded that pheromone traps, as currently used, will not reliably indicate where wireworms occur in a field, and that the complexity of interpreting adult male trap counts limits quantitative predictions of population size.  相似文献   

19.
20.
  • 1 A cloth cage with collecting bottles is described for trapping adult insects emerging from beneath tree bark in low densities.
  • 2 The traps had little effect on temperature, although fluctuations tended to be slightly damped. They probably delayed emergence of adult codling moth, Cydia pomonella by a day or two only.
  • 3 In a test of trap efficiency, all codling moths which developed to the adult stage inside the traps were recorded in the collecting bottles; a few larvae remained in diapause, and the proportion of these was greater in the traps than in an outdoor insectary, so that traps tend to provide a slight underestimate of adult numbers.
  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号