Number Of Target Species Research Articles

Biodiversity Exploitation for Online Entertainment

Anthropogenic wildlife exploitation threatens biodiversity worldwide. With the emergence of online trading which facilitates the physical movement of wildlife across countries and continents, wildlife conservation is more challenging than ever. One form of wildlife exploitation involves no physical movement of organisms, presenting new challenges. It consists of hunting and fishing “experiments” for monetized online entertainment. Here we analyze >200 online videos of these so-called experiments in the world's largest video platform (YouTube). These videos generated about half a billion views between 2019 and 2020. The number of target species (including threatened animals), videos, and views increased rapidly during this period. The material used in these experiments raises serious ethical questions about animal welfare and the normalization of violence to animals on the Internet. The emergence of this phenomenon highlights the need for online restriction of this type of content to limit the spread of animal cruelty and the damage to global biodiversity. It also sheds light on some conservation gaps in the virtual sphere of the Internet which offers biodiversity-related business models that has the potential to spread globally.

Improved freshwater macroinvertebrate detection from environmental DNA through minimized nontarget amplification

Environmental DNA (eDNA) metabarcoding is a new, promising, and non-invasive method to detect biodiversity in aquatic environments. So far, it has mainly been used to screen for fish and amphibian diversity and rarely to detect macroinvertebrates. Typically, DNA metabarcoding relies on PCR amplification of a fragment of the mitochondrial cytochrome c oxidase I (COI) gene with degenerate primers. In comparison to other genes like 16S, COI has a greater taxonomic resolution and availability of an extensive reference database. Benthic stream invertebrates are of critical importance for regulatory biomonitoring, but when using universal primers on eDNA isolated from water, the number of reads and OTUs is “watered down”. This means the target taxa, macroinvertebrates, are underrepresented in comparison to other nontarget taxa, e. g. algae, bacteria, and fungi. The aim of the project was to design an insect-specific primer, which minimizes nontarget amplification. Therefore, data from a time series of 15 months at the Kinzig (Hesse), a silica-rich low-mountain-range stream, which is part of the Rhine‑Main‑Observatory (LTER site) was generated using the universal primers BF2/BR2. With this data we identified the most abundant nontarget taxa and designed a new reverse primer (EPTDr2n) with 3’ ‐ specificity toward benthic invertebrate taxa. Primer specificity was validated in silico together with universal forward primer fwhF2 using available data from GenBank and BOLD. 20 eDNA samples from the Kinzig River and its tributaries were then used to test the new primer in situ together with primer fwhF2. The new primer combination showed a much higher amplification of benthic invertebrates, insects in particular, than two other universal primer pairs for both, number of target reads (fwhF2/EPTDr2n: 99.6% versus BF2/BR2: 25.89% and fwhF2/fwhR2n: 39.04%; Fig. 1) and number of target species (fwhF2/EPTDr2n: 305 versus BF2/BR2: 113 and fwhF2/fwhR2n: 185). Additionally, the number of benthic invertebrate species exceeded even the number of 153 species identified by expert taxonomists at nearby sites across two decades of sampling. While several taxa reported, like a few trichopteran genera, flatworms, and some crustaceans, were not found, the primer shows greatly improved results for eDNA metabarcoding of benthic invertebrates(Leese et al. 2021).

Remote mapping of foodscapes using sUAS and a low cost BG-NIR sensor

The assessment of landscape condition for large herbivores, also known as foodscapes, is fast gaining interest in conservation and landscape management programs worldwide. Although traditional approaches are now being replaced by satellite imagery, several technical issues still need to be addressed before full standardization of remote sensing methods for these purposes. We present a low-cost method, based on the use of a modified blue/green/near-infrared (BG-NIR) camera housed on a small-Unmanned Aircraft System (sUAS), to create foodscapes for a generalist Mediterranean ungulate: the Iberian Ibex (Capra pyrenaica) in Northeast Spain. Faecal cuticle micro-histological analyses were used to assess the dietary preferences of ibexes and then individuals of the most common plant species (n = 19) were georeferenced to use as test samples. Because of the seasonal pattern in vegetation activity, based on the NDVI (Smooth term Month = 21.5, p-value < .01, R2 = 43%, from a GAM), images were recorded in winter and spring to represent contrasting vegetation phenology using two flight heights above ground level (30 and 60 m). Additionally, the range of image pixel sizes was 3.5–30 cm with the smallest pixel size representing the highest resolution. Boosted Trees were used to classify plant taxa based on spectral reflectance and create a foodscape of the study area. The number of target species, the sampling season, the height of flight and the image resolution were analysed to determine the accuracy of mapping the foodscape. The highest classification error (70.66%) was present when classifying all plant species using a 30 cm pixel size from acquisitions at 30 m height. The lowest error (18.7%), however, was present when predicting plants preferred by ibexes, at 3.5 cm pixel size acquired at 60 m height. This methodology can help to successfully monitor food availability and seasonality and to identify individual species.

Conservation Priority Plants in Bukit Barisan Selatan National Park

Bukit Barisan Selatan National Park (BBSNP) has a fairly high biodiversity, including plant species which are categorized as threatened, protected and endemic plants in Sumatra. Information regarding the existence of these plant species is not yet widely available. The purpose of this study was to reveal the existence of threatened, protected and endemic plant species in BBSNP. The research was conducted by exploration methods in three BBSNP areas, namely Kubu Prahu (West Lampung Regency), Sukaraja Atas (Tanggamus Regency) and Rata Agung (Pesisir Barat Regency). A number of target species have been obtained, including 13 threatened plant species, 6 protected plant species, and 7 endemic Sumatran plant species. In addition, three plant species have been included in CITES Appendix 2. The results of the study can be used as a reference for future flora conservation efforts. Keywords: BBSNP, endemic plant, protected, threatened

Year-round cattle and horse grazing supports the restoration of abandoned, dry sandy grassland and heathland communities by supressing Calamagrostis epigejos and enhancing species richness

The spread of competitive grasses, changes in species composition and vegetation structure are direct consequences of grassland and heathland abandonment. As an alternative to more costly management measures such as traditional pastoralism, year-round low-intensity grazing with large herbivores is increasingly used to restore and maintain semi-open habitats. However, the suitability of this grazing regime has not yet been investigated for long-abandoned, highly degraded but nutrient-poor sandy grassland and heathland communities. In particular, it is unclear if year-round grazing is suitable for preventing the further spread of highly competitive grasses such as Calamagrostis epigejos while simultaneously maintaining or improving characteristic species richness and vegetation structure. Hence, we conducted a comprehensive field study on two spatial scales (plot-level: 25m2, macroplot-level: 1ha) to analyse the impacts of year-round low-intensity cattle and horse grazing on the development of the highly competitive grass Calamagrostis epigejos, as well as the vegetation structure and plant species richness of long-abandoned but nutrient-poor dry sandy grassland and heathland communities, their mosaics and Calamagrostis stands within an 800ha heathland between 2008 and 2015. Finally, we assessed the local conservation status of the habitat types after seven years of grazing in comparison to long-abandoned sites.Grazing successfully reduced the coverage of Calamagrostis epigejos, whereby Calamagrostis stands developed towards species-rich sandy grasslands after seven years of grazing. In addition, the quality of the vegetation structure was improved by enhancing the proportion of bare soil, while litter and grass cover, litter thickness and height of the field layer as well as the coverage of ruderal indicators were significantly reduced on grazed sites in comparison to ungrazed sites in 2015. Moreover, we found an overall positive grazing effect on species richness: Total species number, number of target species as well as subordinated target species significantly increased within the vegetation types over time.Thus, year-round low-intensity cattle and horse grazing is a suitable management tool for restoring, maintaining and even improving long-abandoned, nutrient-poor sandy grassland and heathland communities, and thus to enhance the local conservation status of the habitat types. However, if there is a high initial cover of woody species (e.g. shrubs, tree rejuvenation), then an extensive shrub and tree clearance will be necessary, with manual shrub cutting being crucial to reduce the heavy regrowth of the woody species. In addition, a one-time mowing should be implemented in highly degraded heaths to facilitate the vegetative rejuvenation of degenerate stands of Calluna vulgaris, thus improving its attractiveness for the grazing animals.

Restoration of lowland meadows in Austria: A comparison of five techniques

European environmental policy mandates that biodiversity loss should be halted through restoration. However, knowledge about the efficacy of different restoration treatments for lowland meadows is still incomplete. Our study monitored two restoration projects in South-East Austria that served as compensation measures for the loss of species-rich grassland. We compared the efficacy of five restoration techniques: (1) sod transplantation, (2) natural colonization, (3) hay transfer and additions of seed mixtures for (4) wet and (5) bare soils. Over three years, we measured species richness, number of target species, Shannon diversity and similarity to reference sites. We asked: (A) What is the most effective technique for the restoration of lowland meadows? and (B) Is the applied restoration method more important than abiotic site conditions? We included 66 plots (reference and donor sites: 8 plots, restoration sites: 58 plots) in our study. We sampled data on species composition (4m×4m plots) in three consecutive years since restoration initiation, estimated the slope inclination and analyzed soil parameters (K, P, pH). In general, species composition developed towards the reference vegetation for all techniques but sod transplantation produced by far the best result in terms of species richness and similarity to reference sites. By comparison, hay transfer and natural colonization produced intermediate results but performed better than seeding; the latter led to homogenous, species-poor swards. Soil preparation and abiotic site conditions played a minor role in this early stage of the restoration process, though these factors may gain importance in a longer time frame. We found sod transplantation to be a superior method for lowland meadow restoration in our study area but managers must consider its destructive nature and high costs, which might outweigh its benefits. In this light, hay transfer and natural colonization – or a combination of different techniques – could provide less destructive and more cost-effective alternatives.

A test of naturalness indicator values to evaluate success in grassland restoration

How should the somewhat vague term of restoration success be measured? This is a critical question rooted in European law, where in fact the creation of proper replacement habitats is a prerequisite for permitting projects that trigger a loss of species or habitats. Previous studies have used indices that relied on a comparison to reference sites, for example the number of a predefined pool of target species or compositional similarity. However, since restoration sites have rarely the same biotic and abiotic conditions as reference sites, plant communities in restored sites will not perfectly match the reference sites. Furthermore, such indices fail when reference sites are lacking or degraded. Hence, there is a need for an alternative approach that evaluates the conservation value of a restored site independently from reference sites. We propose that naturalness indicator values can be an option to measure restoration success. The approach of using naturalness indicator values makes use of the fact that plants are able to indicate environmental parameters, including degradation and regeneration. We compared and measured the restoration success of three well-established methods for grassland restoration (sod transplantation, hay transfer, seeding) with three commonly used indices (diversity, number of target species, similarity to reference sites). The results verified earlier studies and showed that sod transplantation led to the highest restoration success followed by hay transfer and seeding of sitespecific seed mixtures. Further, we used those well-established indices for an evaluation of novel, naturalness-based indices (unweighted and cover-weighted mean naturalness indicator values, the sum of naturalness indicator values). While calculating the means of naturalness indicator values failed to offer conclusive information on restoration success, we could show that the sum of naturalness indicator values was highly correlated with the number of target species and compositional similarity to reference sites. Thus, our case study demonstrated that naturalness indices can be an excellent option to estimate success in grassland restoration.

Analysis of soil seed bank patterns in an oxbow system of a disconnected floodplain

Soil seed banks have a high potential for vegetation re-establishment in restoration projects. We studied the soil seed bank in an oxbow system of a disconnected floodplain of the Danube River in Southern Germany. The aim of the study was to analyze if floodplain target species were still present in the seed bank after more than 150 years of embankment and disconnection from fluvial dynamics. In this context we investigated seed density, seed bank species richness and species composition in four broad habitat types with and without water-level fluctuations during the time of embankment (permanent water, fluctuating water, reed bed, hardwood floodplain forest). In addition, the similarity between seed bank and above-ground vegetation in these habitat types was studied in order to predict the success of future restoration measures. In total, 124 vascular plant species were determined in the seed bank samples. More than 50 % (66 species) were target species typical for floodplain habitats and 26 of these target species were lost or very rare in the above-ground vegetation. The four habitat types differed significantly in mean seed density and mean species richness. Mean species richness and the number of target species in the seed bank as well as the mean seed density were greatest in the habitats with fluctuating water level whereas mean seed density was much lower in the parts with more or less stable conditions like permanently standing water and hardwood floodplain forest. Sørensen similarity between seed bank and above-ground vegetation was very low in habitats with more or less stable water levels and desirable floodplain target species were very rare or completely absent. Our results indicate that the soil seed bank can be an important seed reservoir for the ecological restoration of floodplain plant communities especially for habitats with unstable environmental conditions during the period of disconnection. Restoration of water level dynamics is important to maintain the seed bank of populations of floodplain target species.

Starch granules identification and automatic classification based on an extended set of morphometric and optical measurements

Starch granules have been found to be preserved in association with archaeological remains and their identification may provide direct botanical evidences of the plants used by ancient humans. However, subtle morphological differences between starch granules make their taxonomic identifications difficult. In order to improve the identification of these plant remains, we used an image analysis program that measures up to 123 different optical and morphological characters. With Random Forest tests we analyzed ~5000 starch granules extracted from underground storage organs (USO), seeds, and fruits of 20 different East African edible plant species. Our results show that correct identification rates are up to 74% for some species (Echinochloa colona, Cyperus rodundus), ~80% for some suprageneric taxa (Poaceae, Fabaceae), and 80% for underground storage organs. However, on average, success rates are just ~53% for species (up to 70% with a dataset reduced to herbaceous species), 60% for families, and 72% for plant parts. Yet, this automated system is not perfect, but it is still more powerful than the human eye, for which the average success rate is just of 25% for species level identifications. We evaluated the performance of our system and found that accuracy rates of identifications of starch granules are highly sensitive to the number of groups (species) to identify (r2=0.83) and, to a lesser extent to the number of characters used by the identification system (r2=0.87). It is therefore crucial to narrow down as much as possible the number of target species, by analyzing additional proxies. We conclude that better results can be achieved if the candidate field is narrowed. If not, the automated identification of starch granules will remain unsatisfactory to provide acceptable interpretations in archaeological contexts.

候鸟类型国家级自然保护区保护成效评估指标体系构建与案例研究

PDF HTML阅读 XML下载 导出引用 引用提醒 候鸟类型国家级自然保护区保护成效评估指标体系构建与案例研究 DOI: 10.5846/stxb201403260563 作者: 作者单位: 1中南林业科技大学野生动植物保护研究所,1中南林业科技大学野生动植物保护研究所,1中南林业科技大学,1中南林业科技大学野生动植物保护研究所,1中南林业科技大学野生动植物保护研究所,2湖南东洞庭湖国家级自然保护区管理局,3青海湖国家级自然保护区管理局;,4中国环境科学研究院,4 中国环境科学研究院 作者简介: 通讯作者: 中图分类号: 基金项目: 环保公益项目科研专项(201209028);国家自然科学基金项目(31472021,31071946);湖南省重点学科建设项目(CSUFT-2013001) Construction of an indicator system and a case study of protection efficacy evaluation of China's national nature reserves for migratory birds Author: Affiliation: 1Institute of Wildlife Conservation,Central South University of Forestry and Technology;Hunan,,1Institute of Wildlife Conservation,Central South University of Forestry and Technology;Hunan,,Central South University of Forestry and Technology;Hunan,,1Institute of Wildlife Conservation,Central South University of Forestry and Technology;Hunan,,1Institute of Wildlife Conservation,Central South University of Forestry and Technology;Hunan,,Hunan East Dongting Lake National Nature Reserve administration;Hunan,China,Qinghai Lake National Nature Reserve administration;Qinghai,China,, Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:建立自然保护区是对生物多样性及其生境最直接、最有效的保护措施,构建一套科学、完整的国家级自然保护区保护成效评估指标体系,对促进国家级自然保护区的有效管理和宏观决策具有重要的意义。截止2014年3月,我国已建立407个国家级自然保护区,其中野生动物类型105个。尽管国家已投入大量的人力、物力和财力,但目前仍不清楚这些国家级自然保护区的保护成效如何,故很有必要对国家级自然保护区保护成效开展评估。基于保护目标物种,以10a为时间尺度,采用集成分析法、专家咨询法和示范研究法,率先构建了我国候鸟类型国家级自然保护区(第一保护对象为候鸟的野生动物类型国家级自然保护区)保护成效评估框架和指标体系,并用层次分析法(AHP)法对指标进行赋分。评估框架包含1个目标层、2个系统层(生态有效性评估,分值占60%;管理有效性评估,分值占40%)、9个因素层、36个指标层,另增加人为影响赋分区(-12分-+8分)。其中,生态有效性评估包含代表性、适宜性、稀有性、多样性、完整性共5个因素层及15个指标层;管理有效性评估包含管理对象、管理行动、管理保障、管理效果共4个因素层及21个指标层。为进一步验证与完善评估指标体系的科学性和可操作性,我们以青海湖国家级自然保护区和湖南东洞庭湖国家级自然保护区为案例进行了研究。结果表明:该评估指标体系具有良好的科学性和可操作性。近10年,青海湖国家级自然保护区在针对保护目标物种种群动态与生境的科研监测、宣传教育、野外巡护、社区共管方面的保护成效较好,但快速发展的生态旅游对候鸟的活动造成了一定的影响,建议加强生态旅游管理;湖南东洞庭湖国家级自然保护区在针对候鸟的宣传教育、野外巡护方面的保护成效较好,但土地管理权属的混乱使候鸟的生境遭到一定的破坏,建议进一步争取土地所有权和落实管理权,并通过发展生态旅游来提高当地居民收入,达到减少人为影响与恢复候鸟生境的目的。 Abstract:The most direct and effective way of protecting biodiversity and their habitats is to establish nature reserves. It has become critically important to establish a comprehensive scientific evaluation index system to assess protection efficacy and promote effective management of China's national nature reserves. Currently, a large number of nature reserves or protected areas have been established worldwide. However, human disturbance and invasion by alien species and other detrimental factors have undermined the ecological benefits of these original habitats. For example, migratory birds still face destruction of their breeding sites, loss of their wintering and stopover sites, and poaching of their non-breeding sites. As of March 2014, 105 national nature reserves specifically for wildlife had been established in China out of a total of 407 national nature reserves. Of these wildlife nature reserves, 22 are designated for migratory birds as the first target of protection through the provision of various kinds of food, habitat, and breeding sites for these birds. Although the Chinese Government has invested a lot of manpower, material, and financial resources in national reserves, their protection efficacy remains unclear. It is, therefore, critical at this juncture to evaluate the protection efficacy of China's national nature reserves for migratory birds to assess their achievements and identify problems, improve effective management effectiveness and biodiversity conservation, and take macroscopic decisions. Different scales of time and space lead to different evaluation results of protection efficacy. We used three methods: integrated analysis, expert consultation, and a case study to develop the first indicator system for evaluating protection efficacy of national nature reserves for migratory birds over the past ten years. The indicator system included one target layer, two system layers (evaluation of conservation effectiveness with a 60% score, and evaluation of management effectiveness with a 40% score), nine factor layers, thirty-six index layers, and seven assigned indexes of anthropogenic influence (-12 points to +8 points). Factor layers of the evaluation of conservation effectiveness included representativeness, suitability, rarity, diversity, and integrity. Factor layers of the evaluation of management effectiveness included management objects, actions, security, and effectiveness. Among the index layers, the number of target species, habitats, water, shelter environments, food resources, routine patrols, environmental quality, and human activities were the focus areas of the indicator system for evaluating protection efficacy. To verify and perfect the evaluation index system, we carried out a case study of the Qinghai Lake National Nature Reserve (QLNNR) and the Hunan East Dongting Lake National Nature Reserve (EDLNNR). The results showed that the evaluation index system demonstrated good scientificity and operability. QLNNR has performed very well in terms of target species monitoring, publicity and education, field patrol, and co-management. However, ecotourism has had some impacts on the activities of migratory birds, so management in this area requires strengthening. EDLNNR has been successful in the areas of publicity and education and field patrol. However, a lack of clarity about land ownership has resulted in a series of adverse consequences. There is, therefore, a need to strive for clarity in terms of land ownership, establishing effective management, and developing ecotourism to improve residents' incomes, and reduce anthropogenic influences to restore the habitats of migratory birds. 参考文献 相似文献 引证文献

Can ecological engineering restore Mediterranean rangeland after intensive cultivation? A large-scale experiment in southern France

Ecological restoration has been identified as one of the possible ways to replace biodiversity loss. While ecological engineering methods can successfully restore some ecosystem attributes, restoration is generally incomplete, mainly due to lack of target species propagule dispersal, unsuitable abiotic conditions and negative biotic interactions, especially after intensive cultivation. How best to restore reference ecosystems is therefore a vital research objective, not only on a small experimental scale but also on a large scale. This study aimed to determine which ecological engineering techniques are the most suitable for large-scale restoration of a low-productive species-rich ecosystem after intensive cultivation. Experiments were carried out at La Crau in southern France, within a 357ha land rehabilitation project whose aim was to recreate a herbaceous sheep-grazed habitat. We investigated: (i) covering species seeding, (ii) topsoil removal, (iii) hay transfer, and (iv) soil transfer as methods to restore a steppe plant community in this rehabilitated area, using the last remaining French Mediterranean steppe as a reference ecosystem. Species-richness, diversity and composition of vascular plant communities were monitored over three years. The rehabilitation made it possible to recover a large area dominated by grasses but with vegetation different from that of the steppe. Hay transfer was successful in transferring some target species, but the number of target species did not significantly increase by the end of the third year. Covering species seeding seemed to provide a suitable area for target species colonization, but probable competition with grasses needs to be monitored. The greatest similarity in richness, diversity, and composition with the reference ecosystem was obtained with topsoil removal and soil transfer, which made it possible to recover the species-richness and, to some extent, the composition of the steppe. Our findings show that current ecological restoration and ecological engineering techniques can lead to at least partial restoration of some ecosystem attributes. However, they also underline the importance of in situ conservation of natural habitats rather than restoring them after their destruction.

Restoration of grasslands on ex-arable land using regional and commercial seed mixtures and spontaneous succession: Successional trajectories and changes in species richness

Dry grasslands in the Protected Landscape Area and Biosphere Reserve of the White Carpathian Mts. in the eastern part of the Czech Republic, central Europe, belong to the species richest plant communities (on a scale of a few m2) in the world. Many of the grasslands were converted to arable land in the second half of the 20th century, but in the past two decades many of the arable fields have been re-grassed, most of them using commercial low-diversity clover-grass seed mixtures, some of them however by spontaneous succession or using a regional species-rich seed mixture. We asked how grasslands restored in various ways differ in their successional trajectories towards long-existing grasslands as reference sites, particularly in species richness and participation of target species.Altogether 35 grasslands restored with a regional seed mixture, 31 restored with commercial seed mixtures, and 16 restored by means of spontaneous succession were compared based on vegetation records (species cover in 5m×5m plots). The data were processed using multivariate statistics.Grasslands restored in the three different ways converged in their species composition and developed generally towards reference grasslands. Considering the number of target grassland species, sowing of regional seed mixtures was the most successful, especially in the beginning, but processes of spontaneous succession led virtually to the same number of target species, even at sites re-grassed with commercial seed mixtures, but more slowly. Development of sites re-grassed spontaneously and by sowing commercial seed mixtures led to the establishment of more mesic vegetation (Arrhenatherion) than when using the regional seed mixture, which was predominantly composed of species typical of dry grasslands (Bromion). Thus, restoration of the most valuable dry grasslands should preferably be based on using properly designed regional seed mixtures.

Nine years of vegetation development in a postmining site: effects of spontaneous and assisted site recovery

Summary1. Highly disturbed areas such as surface‐mined land provide a great challenge for ecological restoration. The goal is to identify appropriate restoration approaches in a continuum between technical reclamation and spontaneous succession. In particular, on slopes endangered by erosion, appropriate methods are needed that quickly establish vegetation cover but also take into account the natural potentials of the site.2. In the mined area Roßbach (Saxony‐Anhalt, Germany), we evaluated the effects of spontaneous succession and assisted site recovery (species introduction through hay transfer and sowing) during a 9‐year experiment. We asked how rates and pathways of vegetation development differ between treatments and whether species composition converges over time owing to species exchange.3. The application of green hay as well as the sowing of regional seed mixtures clearly accelerated vegetation development and led to the rapid establishment of species‐rich grasslands. Hay transfer was most successful owing to the high amount of transferable target species. Moreover, both treatments facilitated the establishment of cryptogams and provided effective erosion control. Also, hay transfer and sowing clearly affected the pathway of succession.Calamagrostis epigejosmigrated from nearby source populations and became increasingly dominant at sites with spontaneous succession. In contrast, the species‐rich grasslands established after hay transfer and sowing were highly resistant to invasion ofCalamagrostisand other ruderals.4. Species exchange between treatments led to increasing similarity in vegetation composition over time. Nine years after implementation of the experiment, we did not find any significant differences between treatments in terms of total vegetation cover, species richness and the number of target species. However, the dominance ratio between target and nontarget species differed significantly. Species introduction through hay transfer and sowing led to a permanently higher abundance of grassland species and a lower coverage of ruderals compared with spontaneously developed sites. Hence, our results highlight the importance of initial floristic composition and the order of species arrivals for long‐term vegetation development.5. Synthesis and applications. Hay transfer and sowing of regional seed mixtures are appropriate restoration tools to achieve rapid revegetation when no potential seed sources of target species are available nearby or there are undesirable species that need to be suppressed. Our results show that introduced grassland species are able to grow under postmining site conditions and can migrate into adjacent spontaneously developing sites. A combination of spontaneous and assisted site recovery can promote the development of species‐rich grasslands in postmining landscapes.

Effects of a Mycoinsecticide on Feeding and Fecundity of the Brown Locust Locustana pardalina

The entomopathogenic fungus Metarhizium anisopliae var. acridum is being developed for use as a mycoinsecticide against locusts and grasshoppers in Africa. In addition to causing significant mortality, studies have shown the pathogen to cause reductions in feeding of a number of target species during the disease incubation period. The present study extends this work by demonstrating significant reductions in feeding following infection in another important pest species, the brown locust Locustana pardalina (Walker). Insects collected from the field following a spray application and subsequently maintained in a field laboratory showed a significant reduction in per capita feeding, as indicated by faecal production, as early as 2 days after treatment; this was before any pathogen-induced mortality. This per capita reduction in feeding by infected individuals contributed to a total reduction in feeding of 65% relative to controls. In addition to this laboratory based assessment, experiments were conducted to examine the effects of infection on mortality, feeding and fecundity in the field. Mortality rates of infected individuals in the field were significantly slower than those in the laboratory (average survival time of approximately 39 days compared with 6 days), although total mortality and percentage mycosis were equivalent. Treated individuals showed a significant reduction in body fat accumulation at sexual maturity compared with controls. This may reduce dispersal ability and total reproductive fitness. However, treated individuals exhibited a reduced pre-oviposition period resulting in them laying more eggs than untreated individuals within the first weeks following fledging. Thus, no significant reductions in fecundity were recorded by the end of the assessment period when mortality of treated individuals exceeded 90%. Given that many untreated locusts were still alive and had the potential to continue oviposition for several more weeks, however, it is likely that differences in fecundity would have become apparent if the assessment had continued. These results provide important insights for evaluating overall impacts of spray applications of the mycoinsecticide.

How small is too small for small animals? Four terrestrial arthropod species in different-sized remnant woodlands in agricultural Western Australia

Island biogeography theory, and the 50/500 rule of genetics, have effectively devalued small habitat fragments for species conservation. Metapopulation theory has given new value to small remnants but data on species persistence are scarce. This study examined the capacity of very small and sheep-grazed remnants of eucalypt woodland in agricultural Western Australia to support remnant-dependent terrestrial arthropods. We surveyed 53 sheep-grazed remnants of wheatbelt wandoo Eucalyptus capillosa for the presence of four species of arthropod with different dispersal strategies (terrestrial versus aerial) and diet (predaceous vs. herbivorous): the harvester and mound-building termite Drepanotermes tamminensis, the wood-eating and mound-building termite Amitermes obeuntis, the predaceous and burrowing scorpion Urodacus armatus and the predaceous 'bull' ant Myrmecia nigriceps. All species with the exception of the scorpion disperse aerially, and all construct above-ground structures that are easily recognized. Remnants ranged in size from 50 m2 to 21 000 m2 (mean 1791 m2), in spatial isolation (distance to the nearest vegetation remnant) from 10 m to 500 m (mean 123 m) and in a length-to-width ratio (shape) from circular (mean ratio 1.0) to linear (mean ratio 4.0). Observations in small and grazed remnants were compared with observations made in six wandoo woodland sites within a large (1040 ha) and ungrazed remnant. The total number of target species was highly correlated with remnant area (r = 0.68). Remnant isolation and remnant shape had no apparent influence on the total number of target species. The minimum area of grazed remnants in which individual species were recorded followed the large predator Urodacus armatus (4515 m2) > smaller predator Myrmecia nigriceps (300 m2) > harvester termites Drepanotermes tamminensis (102 m2) > wood-eating termites Amitermes obeuntis (50 m2). With the exception of U. armatus which occurred only in three of the four largest grazed remnants, the occurrence of all other species increased from small to large grazed remnants, suggesting a remnant-size effect for all species. Remnant isolation or remnant shape had no apparent influence on the occurrence of any one species. The terrestrially dispersing scorpion persisted in remnants despite their isolation from other remnants from 200 m to 500 m. For both termite species, mound heights were significantly greater in large, ungrazed woodlands than in small and grazed woodlands. The incidence of mound abandonment in smaller and grazed remnants was considerably higher for harvester than for wood-eating termite colonies. This suggests differences in spatial requirements and possibly diet-related susceptibilities to fluctuations in food availability. The diameter of Myrmecia nigriceps nests showed no relationship with remnant size or isolation. This study demonstrated that even very small remnant woodlands on farms may play an important role in sustaining small native animals, either as stepping-stones for dispersing individuals (termites, ants) or in providing adequate habitat to sustain populations for longer periods (all four species).

Visual Censusing of Two Coral Fishes Important to the Marine Aquarium Trade.

Although overfishing of edible species has been a substantial factor in the degradation of coral reefs (Hughes 1994), little attention has been paid to the effects of removing selected species of coral fishes for the marine aquarium trade. The global catch of fishes destined for distribution to aquarium hobbyists is substantial, and many of the species selected are important contributors to coral-reef ecosystems. In the U.S. alone, coral fishes are kept in approximately 1% of the estimated 86 million households (Andrews 1990). With few exceptions these specimens are caught wild, often from regions where collecting activities are difficult to monitor (Hingco & Rivera 1991) and population data are lacking. Sensible resource management requires that collections be monitored to minimize habitat destruction and overfishing and that catch limits be based on recruitment dynamics of the target species. Here we assess the populations of adult and juvenile dusky damselfish (Stegastes dorsopunicans) and beaugregories (S. leucostictus) at an unexploited location in the northern part of the Caicos Bank in the Turks and Caicos Islands, British West Indies. Juvenile damselfishes meet the saltwater hobbyist's predilection for species of bright coloration, small size, and extended captive survivorship (Spotte 1993). Our objective was to determine if visual censuses conducted quarterly are sufficiently sensitive to detect natural fluctuations in numbers of target species.