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1.
The knowledge of species occurrence within an area is crucial to develop proper conservation strategies to protect species diversity. Biosphere Reserves (BRs), established to preserve biodiversity and sustainably use their resources, should therefore have precise information of its biodiversity. We compared and evaluated information on threatened and non-threatened vertebrate species available for Spanish BRs from three sources: management documents (MDs), the Global Biodiversity Information Facility index (GBIF), and atlases and red books. Our results suggest that information from any one source was rather partial, to a degree that depended on which vertebrate group was considered. Management documents did list a high percentage of threatened species found in BRs, reaching up to the total number of species of birds and mammals. Species lists overlap between all three sources ranged from 59 % for fish to 84 % for mammals. In addition, there is an inconsistency between national and international threatened species categories and it should thus call for revisions. Even though the information of non-threatened and threatened species occurrence in MDs of Spanish BRs is good, it is necessary to pay attention to amphibian and fish species which are less recorded.  相似文献   

2.
The number of threatened freshwater fish species in Spain is among the highest recorded in Europe and includes a high percentage of endemic taxa. Investigated were the distribution of Spanish freshwater fish to identify priority areas for conservation and assess the extent to which freshwater fish are included in the existing network of protected areas. Considered were those threatened species recorded in the Spanish National inventories. From these data, several biodiversity indices were calculated and analysed. The results reveal important discrepancies between the national and international assessments of conservation status, whereby the current Spanish national catalogue needs updating to reconcile these inconsistencies. Several important areas for the conservation of freshwater fish lie outside protected areas. The results encourage the establishment of protected areas specifically for freshwater environments. An extensive database of Spanish freshwater fish species is needed to redefine priority areas and to maintain freshwater biodiversity.  相似文献   

3.
Syntheses of knowledge are important to reveal trends, biases and gaps in the scientific literature, indicating main data shortfalls and research needs. In this regard, the authors conducted a broad systematic review on the literature about freshwater fish eggs and larvae to investigate (a) temporal trends in the global scientific production, (b) the scope and habitat types, (c) the spatial distribution of studies, (d) the fish species contemplated and their respective conservation status and (e) the factors associated with the spatial distribution of studies. They analysed 654 studies published between 1950 and 2020. The number of studies has increased over time, but with a weak trend. Most studies investigated basic questions about biology and ecology and were carried out chiefly in rivers and lakes. These studies covered 95 freshwater ecoregions (22.3% of all ecoregions) and recorded 871 fish species (4.8% of all freshwater fish currently described). Most species were assessed by the IUCN and classified into six threat categories, but approximately 35% were not evaluated. The main drivers affecting the spatial distribution of studies were ecoregion area, road density, river volume and the number of hydroelectric plants. Results point to significant biases and gaps in the global scientific literature on fish eggs and larvae, especially associated with habitat type, spatial distribution and target species, emphasizing the need to address specific topics. Such biases and gaps indicate the existence of important data shortfalls, which compromise management and conservation planning, as information on fish eggs and larvae is basic and critical for the assessment of fish recruitment and population dynamics.  相似文献   

4.
Freshwater pearl mussels (Margartifera margaritifera L.) are among the most critically threatened freshwater bivalves worldwide. The pearl mussel simultaneously fulfils criteria of indicator, flagship, keystone and umbrella species and can thus be considered an ideal target species for the process conservation of aquatic ecosystem functioning. The development of conservation strategies for freshwater pearl mussels and for other bivalve species faces many challenges, including the selection of priority populations for conservation and strategic decisions on habitat restoration and/or captive breeding. This article summarises the current information about the species’ systematics and phylogeny, its distribution and status as well as about its life history strategy and genetic population structure. Based on this information, integrative conservation strategies for freshwater mollusc species which combine genetic and ecological information are discussed. Holistic conservation strategies for pearl mussels require the integration of Conservation Genetics and Conservation Ecology actions at various spatial scales, from the individual and population level to global biodiversity conservation strategies. The availability of high resolution genetic markers for the species and the knowledge of the critical stages in the life cycle, particularly of the most sensitive post-parasitic phase, are important prerequisites for conservation. Effective adaptive conservation management also requires an evaluation of previous actions and management decisions. As with other freshwater bivalves, an integrative conservation approach that identifies and sustains ecological processes and evolutionary lineages is urgently needed to protect and manage freshwater pearl mussel diversity. Such research is important for the conservation of free-living populations, as well as for artificial culturing and breeding techniques, which have recently been or which are currently being established for freshwater pearl mussels in several countries.  相似文献   

5.
To address the global extinction crisis, both efficient use of existing conservation funding and new sources of funding are vital. Private sponsorship of charismatic ‘flagship’ species conservation represents an important source of new funding, but has been criticized as being inefficient. However, the ancillary benefits of privately sponsored flagship species conservation via actions benefiting other species have not been quantified, nor have the benefits of incorporating such sponsorship into objective prioritization protocols. Here, we use a comprehensive dataset of conservation actions for the 700 most threatened species in New Zealand to examine the potential biodiversity gains from national private flagship species sponsorship programmes. We find that private funding for flagship species can clearly result in additional species and phylogenetic diversity conserved, via conservation actions shared with other species. When private flagship species funding is incorporated into a prioritization protocol to preferentially sponsor shared actions, expected gains can be more than doubled. However, these gains are consistently smaller than expected gains in a hypothetical scenario where private funding could be optimally allocated among all threatened species. We recommend integrating private sponsorship of flagship species into objective prioritization protocols to sponsor efficient actions that maximize biodiversity gains, or wherever possible, encouraging private donations for broader biodiversity goals.  相似文献   

6.
Many freshwater ecosystems and biotas around the world are threatened with extinction. Freshwater fishes, for example, are the most endangered vertebrates after amphibians. Exotic fish are widely recognized as a major disturbance agent for native fish. Evaluating the ecological effects of invaders presents many challenges and the problem is greatly augmented in parts of the world where the native fauna is poorly known and where exotic species are commonplace. We use the fish community of Patagonia, a small and distinct native biota dominated by exotic salmonids, as a case study to ask: what can we learn about the effects of exotic fish species from fragmentary or partial data and how do such data point the way to what needs to be learned? We review the available data and literature on the distribution and status of native and introduced fish. We compile a novel regional presence/absence species database, build fish distribution maps, describe distribution patterns of native and exotic species, and identify critical information voids. A comparative review of literature from Patagonia and Australasia, where a similar native and exotic fish fauna is found, helps us to identify research priorities and promising management strategies for the conservation of native fish fauna. We conclude that the main challenge for fish conservation in Patagonia is to identify management strategies that could preserve native species while maintaining the quality of salmonid fisheries.  相似文献   

7.
The river Ganges is the largest river in India and the fifth longest in the world. Although, many studies on fish ecology and systematic have been conducted largely to improve fisheries but fish diversity and their distribution pattern from conservation point of view have never been adequately addressed in the Ganges. In this connection, current distribution and abundance of freshwater fishes of river Ganges was studied and assessed from April 2007 to March 2009. We documented and described 143 freshwater fish species in the all stretches of the river which is higher than what was reported earlier. Some species were observed with shift in their distribution ranges. First time, a total of 10 exotic fishes, including Pterygoplichthys anisitsi, which has never been reported from India found in the Ganges. Alterations of the hydrological pattern due to various types of hydro projects was seems to be the largest threat to fishes of Ganges. Indiscriminate and illegal fishing, pollution, water abstraction, siltation and invasion of exotic species are also threatening the fish diversity in the Ganges and as many as 29 species are listed under threatened category. The study advocates a need to identify critical fish habitats in the Ganga basin to declare them as conservation reserves to mitigate the loss of fish diversity from this mighty large river.  相似文献   

8.
This report describes the length–weight relationships (LWRs) of 22 freshwater fish species from freshwater western Caribbean drainages in Venezuela. Fishes were collected in dry seasons between 2005 and 2007 with standardized electrofishing from coastal streams of Aroa, Yaracuy and Urama drainages. Results include the first LWR information for ten endemic and threatened species. Novel data on these freshwater fish faunas are important for monitoring their populations, as well as the condition of fluvial habitats to promote strategies for their conservation.  相似文献   

9.
10.
Rates of biodiversity loss are higher in freshwater ecosystems than in most terrestrial or marine ecosystems, making freshwater conservation a priority. However, prioritization methods are impeded by insufficient knowledge on the distribution and conservation status of freshwater taxa, particularly invertebrates. We evaluated the extinction risk of the world''s 590 freshwater crayfish species using the IUCN Categories and Criteria and found 32% of all species are threatened with extinction. The level of extinction risk differed between families, with proportionally more threatened species in the Parastacidae and Astacidae than in the Cambaridae. Four described species were Extinct and 21% were assessed as Data Deficient. There was geographical variation in the dominant threats affecting the main centres of crayfish diversity. The majority of threatened US and Mexican species face threats associated with urban development, pollution, damming and water management. Conversely, the majority of Australian threatened species are affected by climate change, harvesting, agriculture and invasive species. Only a small proportion of crayfish are found within the boundaries of protected areas, suggesting that alternative means of long-term protection will be required. Our study highlights many of the significant challenges yet to come for freshwater biodiversity unless conservation planning shifts from a reactive to proactive approach.  相似文献   

11.
Considering the size of the continent, the Australian freshwater fish fauna is a relatively depauperate one, comprising only about 192 species (belonging to 34 families) which spend significant portions of their life cycles in freshwater habitats. Of these freshwater species, the latest (1989) analysis indicates that six can be classified as endangered, five as vulnerable, four as potentially threatened, two as indeterminate, 32 as restricted, and 16+ as of unknown status, totalling 65 + species. Thus approximately 34% of the entire Australian freshwater fish fauna falls within the above six conservation status categories, which were established by the Australian Society for Fish Biology in 1985. Conservation problems of these fishes, and particularly man-made changes to their habitats, are discussed, and some possible management solutions outlined. Brief mention is also made of several marine species which may also fall into one or more of the above conservation categories, although not enough information is yet available to classify them accurately.  相似文献   

12.
Freshwater fish biodiversity loss in the Mediterranean Basin is regarded as among the highest globally, with long-term population data sets required to discern long-term population trends of threatened species, in order to design appropriate conservation interventions. In this study, we assessed the population trends of two threatened freshwater fishes, Valencia letourneuxi and Valencia robertae, employing the most recent and largest compiled database to date (16 populations over 14 years). We applied the innovative methodology of the Living Planet Index (LPI) to assess the average rate of change over time across a set of V. letourneuxi and V. robertae populations in Greece. The LPI application revealed a dramatic decline of both species, with V. letourneuxi declining by 97.7% and V. robertae by 91.0%. Beta regression showed that water pollution, eutrophication and alien Eastern mosquitofish Gambusia holbrooki’ presence were the three best fitting predictors of the decline of V. letourneuxi and V. robertae populations. Based on the above, we outline the conservation measures urgently required to revert the near collapse of the populations of the two species. Conservation actions include the strict protection of the their lowland spring habitats, habitat improvement through changes in water management and agricultural practices, mosquitofish invasion prevention and mosquitofish impact mitigation measures, as well as translocation actions and captive breeding. Lastly, the association patterns of the proposed conservation actions with anthropogenic pressures and their expected outcomes were analysed through an alluvial diagram, providing insights on the scale of pressures mitigated by conservation actions and on their conservation benefits.  相似文献   

13.
药用植物野生资源的保护正受到学界乃至全社会的广泛关注。本研究通过收集华中地区(包括湖南、湖北和河南三省)的49个国家级自然保护区的科学考察报告、多样性研究报告以及其他相关文献资料, 结合第四次全国中药资源普查数据, 建立了华中地区国家级自然保护区内药用维管植物数据库, 并评估了这些保护区对华中地区药用维管植物的保护成效。研究发现: 华中地区国家级自然保护区内分布有6,071种药用维管植物, 就地保护比例为81.93%; 其中特有、受威胁和常用药用植物物种数分别为1,479种、224种和448种, 三者受保护比例分别为87.98%、78.87%和91.80%。有32.16%的药用维管植物(2,383种, 特有、受威胁和常用药用植物物种数分别为644种、119种和69种)仅分布于1-5个自然保护区中。森林生态系统类型的自然保护区对不同类群药用植物的保护效果均最好。神农架、金童山、莽山、星斗山及湖南舜皇山5个保护区是所有、特有以及受威胁药用植物物种多样性的热点地区, 是华中地区药用植物保护的重要区域。总体上, 华中地区现有国家级自然保护区较好地覆盖了该地区的药用维管植物, 但药用维管植物的就地保护仍不容懈怠。建议加强对该区域保护空缺物种的野外动态监测和保护。  相似文献   

14.
Various factors constrain the existence and development of inland fishes and fisheries, such as pollution, habitat degradation, alien invasive species, local user conflicts, low social priority and inadequate research and funding. In many cases, however, degradation of the environment and loss of aquatic habitat are the predominant concerns for the conservation of freshwater aquatic biota. The need for concerted effort to prevent and reduce environmental degradation, as well as protection of freshwater fishes and fisheries as renewable common pool resources or entities in their own right, are the greatest challenges facing the conservation of fishes in inland waters. Unfortunately, traditional conservation practices such as regulation of exploitation, protected areas and habitat restoration have failed to arrest the alarming increase in number of threatened freshwater fish species worldwide. This paper examines the shifting paradigm of fisheries management from rule-based regulation, through fishery enhancement towards the ecosystem approach to fisheries, with reference to inland waters, and how the emerging concept of ecosystem services coupled with traditional fish conservation management practices, institutional restructuring and integrated management planning should provide a more sustainable thrust to formulation and promotion of fish conservation initiatives.  相似文献   

15.
Although China has established more than 600 wetland nature reserves, conservation gaps still exist for many species, especially for freshwater fishes. Underlying this problem is the fact that top-level planning is missing in the construction of nature reserves. To promote the development of nature reserves for fishes, this study took the middle and lower reaches of the Yangtze River basin (MLYRB) as an example to carry out top-level reserve network planning for fishes using approaches of systematic conservation planning. Typical fish species living in freshwater habitats were defined and considered in the planning. Based on sample data collected from large quantities of literatures, continuous distribution patterns of 142 fishes were obtained with species distribution modeling and subsequent processing, and the distributions of another eleven species were artificially designated. With the distribution pattern of species, Marxan was used to carry out conservation planning. To obtain ideal solutions with representativeness, persistence, and efficiency, parameters were set with careful consideration regarding existing wetland reserves, human disturbances, hydrological connectivity, and representation targets of species. Marxan produced the selection frequency of planning units (PUs) and a best solution. Selection frequency indicates the relative protection importance of a PU. The best solution is a representative of ideal fish reserve networks. Both of the PUs with high selection frequency and those in the best solution have low proportions included in existing wetland nature reserves, suggesting that there are significant conservation gaps for fish species in MLYRB. The best solution could serve as a reference for establishing a fish reserve network in the MLYRB. There is great flexibility for replacing selected PUs in the solution, and such flexibility facilitates the implementation of the solution in reality in case of unexpected obstacles. Further, we suggested adopting a freshwater management framework in the implementation of such solution.  相似文献   

16.
Conservation status assessments are one of the key scientific measures to inform solutions aiming at minimizing the biodiversity crisis of the Anthropocene, being the IUCN’s Red List approach the most widely used and accepted tool for species-level assessment. However, Red Lists are time-consuming because they necessarily rely on expert evaluation. Thus, the development of automated tools, able to handle the huge increasingly amount of data in less time, are useful for guiding conservation actions. In this sense, the aim of this research is to evaluate an automated preliminary conservation status assessment for all known endemic flora from the megadiverse Brazil. Vascular taxa were derived from the Brazilian Flora 2020 project and occurrences were retrieved from GBIF and SpeciesLink. Data was filtered and then evaluated with the aid of ConR package and high resolution nationwide vegetation maps. The current approach estimates that 28.78 % (22.72–43.75 %) of the endemic flora is threatened by extinction, with different patterns between the six Brazilian ecoregions: from 30.75 % (Amazonia’s lower) to 100 % (Pantanal’s best/upper). The high variation in the estimate is because more than a fifth of the vascular flora is poorly known (<3 records). Accuracy assessment reveals a good agreement between the reference from the Brazilian Flora 2020 project and a binary classification (threatened/not- or near-threatened), with an overall accuracy of 61.67 % (58.84–64.47 %), but with limited capacity to distinguish between the IUCN’s threat levels (Critically Endangered, Endangered and Vulnerable to extinction). Bromeliaceae and Orchidaceae are the families with higher estimated number, proportion in relation to the whole family and uncertainty of estimated threatened species, reflecting that herb is the life form with far more threatened species, followed by shrubs. The presented approach can serve as rapid assessment tool for optimizing efforts and to identify potentially threatened species and hotspots of species that could be considered for timely and effective conservation actions. As a practical recommendation, botanists could prioritize the assessment of the species indicated here as threatened, as there is a high chance of confirming this status, and efforts can be properly addressed for their conservation. Moreover, the automated approach can be useful for monitoring the progress of conservation targets. Finally, further scientific research is urgent to fill the knowledge gap on the Brazilian flora aiming at its conservation.  相似文献   

17.
To elucidate the factors underlying species conservation priority setting, we analysed the relationships among species’ structural complexity, scientific attention, threatened species listing, and conservation investments at different organisational levels, including global, European, national, and sub-national. Although the literature often highlights the need to consider criteria other than extinction risk status, our results show that an excessive use of Red lists still persists in the setting of conservation priorities. We found that organismal complexity, available scientific information, and species listing combine together to create a positive feed-back loop, in which more complex organisms have a larger proportion of threatened species in the Red lists and legal lists. This bias promotes research that is devoted to understanding conservation problems as well as more funds invested to solve them. We propose that a sort of pitfall-trap is currently constraining the species conservation priority setting, in which few species, mainly threatened and better-known species, tend to receive most of the funds and policy attention. To counteract this pitfall-trap, we highlight the need to increase scientific effort on lower taxa and expand Red lists to assess lesser-known taxonomic groups as well as the need to use other criteria for species conservation prioritisation.  相似文献   

18.
叶超  刘锋  安明态  杨焱冰 《广西植物》2022,42(2):240-246
兰科(Orchidaceae)植物是植物界中最进化、种类最丰富的类群之一,有较高的环境要求和较强的生态系统依存性.由于很多兰科植物具有较高的观赏价值和药用价值,各地采挖频繁,导致其受威胁十分严重,已成为保护植物中的"旗舰"类群.该文基于文献资料和近年来课题组野外调查数据,分析贵州省野生兰科植物的地理分布状况、就地保护现...  相似文献   

19.
The current freshwater fish fauna crisis is such that natural resource managers urgently need to identify priorities and understand the management consequences of actions aimed at maximizing the preservation of biodiversity. Freshwater research is often poorly linked to conservation ecology; and interdisciplinary studies illustrating examples of freshwater ecosystem conservation are scarce. The Iberian Peninsula has a long history of anthropogenic disturbance that has led to the poor conservation status of its ichthyofauna, with 52 % of species now catalogued as critically endangered, endangered or vulnerable, according to UICN criteria. This paper gives an overview of the main threats (habitat degradation, hydrological alterations and exotic species) that have altered the function and connectivity of Iberian rivers. Case-study examples are provided to analyse the repercussions of these threats and the management actions planned or already performed in these systems. The interaction of many threats is responsible for native fish decline. However, freshwater managers and researchers should not let the trees prevent them from seeing the overall wood, when seeking to achieve practical solutions with the best balanced cost benefit and the collaboration of all ecosystem researchers and stakeholders. Conservation efforts should be focused on the preservation of ecological processes, in order to achieve the goals of the Water Framework Directive and guarantee the conservation of Iberian native fish species.  相似文献   

20.
Monitoring endangered freshwater biodiversity using environmental DNA   总被引:4,自引:0,他引:4  
Freshwater ecosystems are among the most endangered habitats on Earth, with thousands of animal species known to be threatened or already extinct. Reliable monitoring of threatened organisms is crucial for data‐driven conservation actions but remains a challenge owing to nonstandardized methods that depend on practical and taxonomic expertise, which is rapidly declining. Here, we show that a diversity of rare and threatened freshwater animals—representing amphibians, fish, mammals, insects and crustaceans—can be detected and quantified based on DNA obtained directly from small water samples of lakes, ponds and streams. We successfully validate our findings in a controlled mesocosm experiment and show that DNA becomes undetectable within 2 weeks after removal of animals, indicating that DNA traces are near contemporary with presence of the species. We further demonstrate that entire faunas of amphibians and fish can be detected by high‐throughput sequencing of DNA extracted from pond water. Our findings underpin the ubiquitous nature of DNA traces in the environment and establish environmental DNA as a tool for monitoring rare and threatened species across a wide range of taxonomic groups.  相似文献   

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