阎甲采集方法的比较及应用

结合阎甲的生活习性介绍了野外采集阎甲科昆虫的方法,主要分为客观采集法(包括引诱物法、土网筛法、巴氏罐诱法和灯诱法)和特殊生境(树皮下、动物巢穴和储藏物)主观采集法;并比较各种方法的特性和优缺点,认为引诱物法采集效率最高。通过分析各种方法所采集的主要阎甲种类,说明主观采集法的类群针对性强。探讨各种采集方法在不同研究方向的现状和潜在的应用前景。     

陷阱法和Winkler法调查土壤节肢动物多样性比较:以千岛湖岛屿封闭生境研究为例

陷阱法和Winkler法是调查土壤动物的两种常规方法,然而这两种方法的调查效率各有优劣。本研究于2010年秋季,在千岛湖中心湖区选取了15个面积不同的岛屿,同时采用Winkler法和陷阱法采集岛屿上的土壤节肢动物,在岛屿这一封闭生境中比较两种方法收集土壤节肢动物的效率。结果表明,两种方法捕获土壤动物类群丰富度差异不显著,但多样性指数差异极显著。Winkler法对常规土壤节肢动物类群的采集效率优于陷阱法,尤其对运动较缓慢、活动范围较小的土壤节肢动物类群的采集具有优势;陷阱法则更优于采集运动能力较强、活动范围较大的类群。基于样方的稀疏曲线结果说明,Winkler法能用少量样方快速获取研究区域的土壤节肢动物群落基本组成,推荐在面积较小的岛屿上使用;而在面积较大的岛屿上使用陷阱法能够获取更多的类群。ChaoJaccard相似性系数比较则显示两种方法所取的土壤节肢动物相似性在大型岛屿上差异较大,说明大样本数据的采集需要两种方法同时使用能够提高数据的完整性和可靠性。本研究的结果为土壤节肢动物研究的方法选择提供了数据支持,具有一定的实际应用性。     

Spatio-temporal patterns of ground-dwelling ant assemblages in a lowland rainforest in southeast Cameroon

We studied the spatio-temporal patterns of ground-dwelling and -foraging ant assemblages in a continuous mixed secondary lowland rainforest on the northern periphery of the Dja Biosphere Reserve in southeast Cameroon. The effect of season and of the interaction of season with vegetation type on ant species density, activity and composition were investigated. We also checked for a possible impact of army ant activity on the ant assemblage. Ants were collected by pitfall trapping in seven vegetation types in each of three seasons during 12 months in 2003 and 2004–2005. Season significantly influenced the ground-dwelling ant assemblage. The late wet season had the lowest ant species density and a different species composition than the early wet and the dry season. Also inter-annual variation in ant species density and composition was detected and could partly be explained by an influence of Dorylus activity. In general, vegetation type and inter-annual variation had a larger influence on the ground-ant assemblage than season. Significant effects of interactions between season, year, vegetation type and army ants on the ant assemblage confirm that also in African rainforests ant assemblages are extremely dynamic and depend on a complex combination of availability of food resources, nest sites and predators. Received 4 October 2006; revised 4 June 2007; accepted 2 July 2007.     

A census of a community of small terrestrial vertebrates

A small vertebrate community of eighteen terrestrial species was revealed by removal trapping in 1 ha of Western Australian Banksia woodland in autumn. Nine of these species were lizards, three were mammals, three were snakes and three were frogs. The use of pitfall and mammal traps on an 8 × 8 m grid was shown to be sufficient to census the majority of terrestrial species in the study site. A biomass of 2063 g/ha of terrestrial species was estimated from trapping records. Frogs (three species) had the greatest biomass (41% of total), but the introduced mouse Musmusculus contributed the greatest biomass (36%) of any single specie.     

Pitfall trapping of scarce Orthoptera at a coastal nature reserve in Essex, UK

The value of pitfall trapping was questioned in a recent review of methods for sampling Orthoptera in grassland ecosystems. However, subsequent to the publication of this review, interesting data has become available from pitfall trapping at Colne Point, an important coastal nature reserve in Essex, UK. As a result of this trapping, the nationally scarce and Essex Red Data List species, Platycleis albopunctata, was rediscovered in the county. This tettigoniid was believed to be extinct in Essex as previous visual searches for the insect at Colne Point had failed to locate it. Large numbers of the Essex Red Data List species, Myrmeleotettix maculatus, were also captured, as were specimens of the nationally scarce cockroach, Ectobius panzeri (Dictyoptera). Systematic pitfall trapping at Colne Point was therefore pivotal in recording scarce species such as P. albopunctata which had proved difficult to locate by visual searching methods.     

Hand searching versus pitfall trapping: how to assess biodiversity of ground beetles (Coleoptera: Carabidae) in high altitude equatorial Andes?

The use of ground beetles (Coleoptera: Carabidae) as bioindicators of environmental change depends on the reliability and the effectiveness of the sampling methods. Those that have been tested in the temperate zone and in tropical forests still await experimentation in tropical high-altitude environments. For the first time, pitfall trapping and hand searching have been compared in Ecuadorian páramo above 4000 m a.s.l., in terms of practical effectiveness. The study was performed on six volcanoes and was based on the comparison of 28 sampling sessions (pitfall trapping and hand searching) performed along two different elevational belts [lower superpáramo (LSP) and upper superpáramo (USP)]. Analyses of sampling sessions showed that detected species richness is slightly higher with hand searching than with pitfall trapping, regardless of the elevation. Additionally, hand searching is more time-effective than pitfall trapping. The performance of the sampling method slightly varies when species assemblage composition is analysed in relation to elevational belts. In the LSP, hand searching and pitfall trapping should be simultaneously used to obtain exhaustive inventories of carabid biodiversity, since different species are likely to be collected by each method. In the USP, hand searching and pitfall trapping efficiency is very similar, but hand searching allows to collect a slightly larger number of species. Lastly, the sample-based rarefaction curves showed that four temporal replicates are mandatory to obtain a robust dataset and an exhaustive inventory of the true species richness and species assemblages composition. Our findings suggest a combined use of hand searching and pitfall trapping in the LSP, while both methods can be used alone for surveying carabids in the USP. Furthermore, hand searching is recommended if the aim is to obtain an inventory of species diversity, whereas pitfall trapping seems more convenient for fine grain ecological and comparative studies.     

A comparison of pitfall traps with bait traps for studying leaf litter ant communities.

A comparison of pitfall traps with bait traps for sampling leaf litter ants was studied in oak-dominated mixed forests during 1995-1997. A total of 31,732 ants were collected from pitfall traps and 54,694 ants were collected from bait traps. They belonged to four subfamilies, 17 genera, and 32 species. Bait traps caught 29 species, whereas pitfall traps caught 31 species. Bait traps attracted one species not found in pitfall traps, but missed three of the species collected with pitfall traps. Collections from the two sampling methods showed differences in species richness, relative abundance, diversity, and species accumulation curves. Pitfall traps caught significantly more ant species per plot than did bait traps. The ant species diversity obtained from pitfall traps was higher than that from bait traps. Bait traps took a much longer time to complete an estimate of species richness than did pitfall traps. Little information was added to pitfall trapping results by the bait trapping method. The results suggested that the pitfall trapping method is superior to the bait trapping method for leaf litter ant studies. Species accumulation curves showed that sampling of 2,192+/-532 ants from six plots by pitfall traps provided a good estimation of ant species richness under the conditions of this study.     

Acoustic activity across a seabird colony reflects patterns of within-colony flight rather than nest density

Passive acoustic monitoring is increasingly being used as a cost-effective way to study wildlife populations, especially those that are difficult to census using conventional methods. Burrow-nesting seabirds are among the most threatened birds globally, but they are also one of the most challenging taxa to census, making them prime candidates for research into such automated monitoring platforms. Passive acoustic monitoring has the potential to determine presence/absence or quantify burrow-nesting populations, but its effectiveness remains unclear. We compared passive acoustic monitoring, tape-playbacks and GPS tracking data to investigate the ability of passive acoustic monitoring to capture unbiased estimates of within-colony variation in nest density for the Manx Shearwater Puffinus puffinus. Variation in acoustic activity across 12 study plots on an island colony was examined in relation to burrow density and environmental factors across 2 years. As predicted fewer calls were recorded when wind speed was high, and on moon-lit nights, but there was no correlation between acoustic activity and the density of breeding birds within the plots as determined by tape-playback surveys. Instead, acoustic indices correlated positively with spatial variation in the in-colony flight activity of breeding individuals detected by GPS. Although passive acoustic monitoring has enormous potential in avian conservation, our results highlight the importance of understanding behaviour when using passive acoustic monitoring to estimate density and distribution.     

The energetic equivalence rule rejected because of a potentially common sampling error: evidence from carabid beetles

Abundance data from pitfall traps are widely used to estimate the relationship between beetle body size and abundance. Such data probably overestimate densities of large bodied species and may overestimate slopes of size‐abundance relationships. Here, we test this idea by comparing size‐abundance patterns found using data from pitfall trapping with those found with data from a quantitative method of estimating abundance, quadrat sampling. We use data from a total of 47 communities. As expected, slopes of size‐abundance relationships are significantly more positive when estimated using data from pitfall traps compared to when using quadrat sampling data. This was seen when looking across different communities, within communities sampled by both methods and when focusing on the set of species found by both methods within a community. These results were also generally found regardless of method of analysis, which were done using regression with species values as independent data points and using the independent contrast method, and with slopes estimated using ordinary least square regression or the structural relation. Most important, slopes of size‐abundance relationships based on data from pitfall traps were on average significantly more positive than ?0.75 on log–log scales, and thus inconsistent with the energetic equivalence rule. Slopes based on quadrat sampling, on the other hand, were on average not significantly different from ?0.75. The rejection of the energetic equivalence rule based on data from pitfall traps here is therefore a sampling artefact. Similar problems may apply to abundance data from virtually all insect trapping methods, and should make us consider re‐examining many of the size‐abundance patterns documented so far. As a large proportion of all animal species are insects, and traps are widely used to estimate abundance, this is a potentially important problem for our general understanding of the relationship between species body size and abundance.     

A survey of the apes in the Dzanga-Ndoki National Park, Central African Republic: a comparison between the census and survey methods of estimating the gorilla (Gorilla gorilla gorilla) and chimpanzee (Pan troglodytes) nest group density

A survey of apes was carried out between October 1996 and May 1997 in the Dzanga sector of the Dzanga‐Ndoki National Park, Central African Republic (CAR), to estimate gorilla (Gorilla gorilla gorilla) and chimpanzee (Pan troglodytes) densities. The density estimates were based on nest counts. The strip transect census and the line transect survey method (Standing Crop Nest Count) were used to estimate the gorilla nest group density. The strip transect has been most commonly used to date. It assumes that all nest groups within the width of the strip are detected, but as this assumption is easily violated in the dense tropical rain forest, the line transect survey was also used. In this method, only the nest groups on the transect line itself should be detected. This method proved to be an adequate and easy technique for estimating animal densities in dense vegetation. The gorilla density of 1.6 individuals km^?2 (line transect survey method) found for the Dzanga sector is one of the highest densities ever reported in the literature for the Western lowland gorilla. The density estimate for chimpanzees was 0.16 individuals km^?2 (census method). The results of this study confirm the importance of the Dzanga‐Ndoki National Park for primate conservation.     

Spatial heterogeneity in predator activity, nest survivorship, and nest-site selection in two forest thrushes

The ability of prey to find and use predator-free space has far-reaching consequences for their persistence and interactions with their predators. We tested whether nest survivorship of the ground-nesting veery (Catharus fuscescens) and shrub-nesting wood thrush (Hylocichla mustelina) was related to the local absence of a major nest predator, the white-footed mouse (Peromyscus leucopus). Mouse-free space was defined by trap stations that failed to trap a mouse during the avian breeding season (~May through July). In addition, mouse activity was quantified at individual trap stations based on the number of captures during the same period (six 2.25-ha trapping grids, each containing 121 trap stations trapped repeatedly throughout the summer between 1998 and 2002.) Annual mouse-free space was correlated with other measures of mouse activity based on trapping data. Both mouse-free space and activity metrics were significantly related to annual rates of nest predation (i.e., nest daily mortality rate) in veery but not wood thrush. Likewise, mouse-free space and mouse activity within the nest neighborhood (~30×30 m² surrounding each nest) was significantly related to nest survivorship in veery but not wood thrush. More trap stations had consistently greater (hotspots) and lesser (coldspots) mouse activity than expected by chance, and veeries were significantly more likely to nest near stations that had below the grid-average trapping success. Our study thus documented significant spatial variability in predator activity and its relationship to nest predation and nest-site selection in a ground-nesting songbird.     

Counting primates for conservation: primate surveys in Uganda

Primate census techniques have been developed over the past 35–40 years yet there is still some confusion and great variation in the methods used. This precludes comparisons between sites where different techniques have been used. This paper discusses the variations between the methods that seem to be practiced currently and then describes a census of primates in the forests of western Uganda. Primate density and biomass varied greatly between forests as well as within forests and this is probably related to food availability. Chimpanzee (Pan troglodytes) density was strongly correlated with nest encounter rates from reconnaissance walks in the forest. This result can be used to estimate chimpanzee density in forests where it is difficult to survey this species (e.g., due to security reasons). A total of 4,980 chimpanzee was estimated for Uganda which is higher than previously guessed, but still of conservation concern. Only four forests had more than 500 individuals which gives concern for long-term population viability.     

相机陷阱法在潮间带底栖蟹类群落生态学中的应用研究

潮间带大型底栖动物调查是滨海湿地生物多样性监测的重要环节。目前普遍应用的传统侵入性调查方法（挖掘法、手捕法和陷阱诱捕法）存在干扰强、耗时久和劳动密集等问题,无法客观反映活动性较强的蟹类等重要功能类群的群落结构和物种多样性。对陆地野生动物研究中常用的相机陷阱法进行了符合潮间带应用条件的便携式设计,并以红树林蟹类为例,通过与3种传统侵入性调查方法进行对比,探讨相机陷阱法在潮间带底栖蟹类群落生态学研究中的应用。结果表明：（1）相机陷阱法在种群密度测定方面比挖掘法提高2.1倍,比手捕法提高10.3倍,比陷阱诱捕法提高16.3倍;（2）相机陷阱法在调查物种数方面均高于3种传统侵入性调查方法,适用于沙蟹科（Ocypodidae）和方蟹科（Grapsidae）蟹类调查;（3）相机陷阱法对个体大小选择性弱,采样更加全面;（4）相机陷阱法在群落alpha多样性（Shannon-Wiener指数）、beta多样性（样方-多度矩阵总方差Var （Y））和功能多样性（Rao二次熵和功能离散度）调查方面整体不弱于侵入性调查方法。此外,相较于侵入性调查方法,相机陷阱法对沉积物结构破坏小、不干扰蟹类群落结构,在兼顾数据丰富性的同时又具有高效性。然而,由于相机陷阱法基于蟹类底表活动性,无法适用于冬季调查、夜行性蟹类和游泳型蟹类调查。未来,相机陷阱法的发展将与基于深度学习的图像处理技术结合以满足数据处理需求。研究揭示了相机陷阱法在潮间带底栖蟹类群落中的应用优越性与局限性,为潮间带大型底栖动物群落生态学的研究提供技术支撑。     

Monitoring of the ground-dwelling beetle community and forest floor environment in 22 temperate forests across Japan

This data paper reports census data of ground-dwelling beetle and other fauna of the forest floor environment; collections were made from a network of 22 forest sites in Japan. To our knowledge, this represents the largest dataset for long-term monitoring of a ground-dwelling beetle community and other taxa in a ground environment in forests, which covers a broad climatic range in the temperate zone and is freely available. The network forms part of the Monitoring Sites 1000 Project launched by the Ministry of the Environment, Japan. It covers subalpine, cool- and warm-temperate and subtropical climatic zones and the four major forest types of Japan. Thirty-three permanent plots usually 1 ha in size were established in old-growth, secondary natural and a few plantation forests. Censuses of the ground-dwelling beetle community were conducted using pitfall trapping and forest floor environment monitoring every year from 2004 to the present. During the initial 9 years of the census (2004–2012), 59,762 beetle individuals (including 3182 larvae) of more than 314 species were recorded. This dataset includes taxonomy and biomass of each beetle individual and each taxonomic group of other invertebrates coincidently captured in pitfall trapping. The dataset also includes data related to ground coverage by forest floor vegetation, dry mass of the accumulated organic litter layer, and carbon and nitrogen contents and cellulose decomposition rate in organic layer and surface mineral soil. The data could be used to investigate geographical patterns and intra- and inter-annual dynamics of individual body mass, populations and community structures of ground-dwelling beetles, and their relationships with the forest floor environment. Furthermore, the data could be analyzed with other open datasets related to tree community dynamics and litter fall continuously measured in the same study plots. This dataset also provides information related to the distribution and average body mass of each beetle species.     

Is pitfall trapping a valuable sampling method for grassland Orthoptera?

Common methods to assess diversity and abundance of Orthoptera are sweep netting, transect counts and box-quadrat sampling. Pitfall trapping, by contrast, is rarely used, and the value of this method is still being questioned. In 2008, we studied Orthoptera species richness and abundance in five vegetation types along a gradient of dune succession on the Baltic Sea island of Hiddensee (NE Germany) by comparing transect-count and pitfall-trapping data. Using transect counts, 12 species were detected in the study area. With pitfall traps, three chorto- and thamnobiont Ensifera species (C. dorsalis, M. roeselii and T. viridissima) were not caught at all, and it was only in low-growing and sparsely-vegetated grey dunes that all present species were detected. With pitfall traps, the proportion of present species recorded strongly declined with increasing height and density of the vegetation type. Assuming that transect counts are a good proxy for relative Orthoptera densities, densities ascertained by pitfall traps are strongly biased by vegetation structure and locomotive behaviour of the species. More than 80% of all individuals were caught in sparsely-vegetated grey dunes. Frequency patterns of the species also differed. Using pitfall traps, especially chortobiont species were significantly underrepresented. Qualitative and quantitative sampling of Orthoptera using pitfall traps seems only reasonable in habitats with low and sparse vegetation and a high proportion of geobiont species.     

笼捕法和陷阱法对森林小型兽类多样性监测效率比较

<正>小型兽类包括食虫目(Insectivora)、啮齿目(Rodentia)、翼手目(Chiroptera)、兔形目(Lagomorpha)等,物种数量多,分布广,适应能力强,对环境变化敏感,因此其群落组成和种群数量变化可较好地反映生境变化的质量和人类活动的干扰程度(肖治术等,2002;李俊生等,2003;仝磊和路纪琪,2010)。小型兽类多样性一直是生物多样性和生态环境监测与评价的重要指示类群之一(周立志和马勇,2002)。统计动物毛发、粪便、巢穴、叫声、足迹等动物痕迹以及直接观察等方法已被广泛用于兽类物种监测和种群密度估计(Eberhardt and Van Etten,1956;Bider,1968;Gannon     

Diversity and composition of epigeal arthropods using pitfall trapping method in different habitat types of Abu Dhabi Emirate,UAE

Pitfall trapping is an efficient self-sampling method for capturing epigeal arthropods for ecological and faunistic studies. During the present study, conducted between March 2009 and March 2015, pitfall trapping was undertaken in five study sites of different habitats in Abu Dhabi Emirate. During the study period a total of 94 monitoring visits were made to collect data from the pitfall traps at five sites in Abu Dhabi. A total of 36,238 individuals of ground-dwelling arthropods of 121 different species belonging to 14 orders and 46 families were recorded from all the study sites using pitfall traps. The order Coleoptera (beetles) was recorded to be the most dominant order with 46 species followed by Hymenoptera (ants, bees & wasps) with 24 species. On average 37.5 ± 3 (mean ± SE) species were recorded every month from all the study sites and number of species did not vary significantly across the months (df = 11, F = 0.48, p = 0.91 one-way – ANOVA). The arthropod fauna was recorded to be highly diversified in different habitat types, but the number of individuals were not evenly distributed across the study sites (H) 1.10, (E) 0.53, Shannon Diversity Index). The highest diversity of arthropods was recorded from a site Wadi Tarabat, followed by Al Wathba Wetland Reserve (AWWR) and Abu Al Abyed. Our findings indicate that to study ground dwelling invertebrate species, pitfall trapping is an efficient method. Moreover, capture efficiency of pitfall traps can be affected by climatic factors and habitat types of Abu Dhabi Emirate. The ideal period to encounter the highest number of species is between March to April and September to November across all the habitat types.     

Extended Application of a Marked-Nest Census Method to Examine Seasonal Changes in Habitat Use by Chimpanzees

The Kalinzu Forest Reserve in Uganda comprises various types of vegetation, including mixed mature forest, Parinari-dominated mature and secondary forest, and Musanga-dominated secondary forest. We used a marked-nest census method to examine seasonal changes in chimpanzees' use of the different vegetation types. We made 10 parallel line-transects in the study area; they were 5-km long and 500-m apart. During the first 3–4 walks along the transects, we marked all existing nests. We then conducted 10 main censuses of all transects at 15-day intervals, over a total period of about 5 months. In each main census, we recorded all unmarked nests visible from the transects and marked them. When we saw a nest, we searched for neighboring nests of the same age class 30 m of each other, in order to estimate the size and position of nest groups. To improve the accuracy of the estimation of nest density in each census period, we excluded nests that consisted only of brown leaves and corrected the number of nests observed by allowing for the proportion of newly-built nests that would still have green leaves at the next main census. We estimated the population density of chimpanzees in the study area both by the number of individual nests and by the number of nest groups; the two methods gave similar results. We found differences in number of chimpanzees that used different vegetation types in different fruiting seasons, and differences in nest group size related to the different fruiting seasons.     

Relative efficiency of pitfall trapping and hand-collecting from plots for sampling of millipedes

Millipedes were sampled by hand-collecting from plots and by pitfall trapping at three forest sites in central Tasmania. Seven days of pitfall trapping each month over one year was less efficient than four weeks of hand-collecting in autumn, yielding fewer species and fewer specimens per working day in the field. Hand-collecting is likely to provide more accurate data on species diversity and relative abundance for a range of litter invertebrates.     

The beetle fauna of remnant eucalypt woodlands from the Northern Plains Victoria Australia

The abundance, richness and trophic structure of beetle assemblages (Insecta: Coleoptera) from remnant eucalypt woodlands of the Northern Plains, Victoria, is documented. Three sampling methods (pitfall trapping, direct searching, sweep netting) were used to sample beetles in four seasons over a year. A total of 4487 beetles were sorted into 342 morphospecies from 46 families. Pitfall trapping alone caught the greatest number of families (72%), morphospecies (56%) and specimens (50%). However, direct searching and sweep netting yielded a large number of morphospecies not caught by pitfall trapping. Sampling in summer yielded the greatest number of families (78%) and morphospecies (55%) but the most specimens (31%) were caught during winter. The proportions of different trophic groups varied little across different seasons but greatly for sampling methods. Pitfall trapping caught a higher proportion of predators and a lower proportion of herbivores than other sampling methods. Direct searching caught mostly herbivores, whilst sweep netting captured a large number of fungivores. The results have implications for the design of sampling sets for inventory surveys of invertebrate groups.