Contributions of ethnobiology to the conservation of tropical rivers and streams

• 1. This study aimed to link basic ethnobiological research on local ecological knowledge (LEK) to the conservation of Brazilian streams, based on two case studies: original data on LEK of fishermen about freshwater fish in the Negro River, Amazon, and previously published data about LEK of farmers on the ecological relationship between forest and streams in the Macabuzinho catchment, Atlantic Forest.
• 2. Information was obtained from fishermen through interviews using standard questionnaires containing open-ended questions. Informants for interview were selected either following some defined criteria or applying the ‘snowball’ method.
• 3. Fishermen's LEK about the diets and habitats of 14 fish species in the Negro River provided new biological information on plant species that are eaten by fish, in addition to confirming some ecological patterns from the biological literature, such as dependence of fish on forests as food sources.
• 4. In the Atlantic Forest, a comparison between farmers' LEK and a rapid stream assessment in the farmers' properties indicated that farmers tended to overestimate the ecological integrity of their streams. Farmers recognized at least 11 forest attributes that correspond to the scientific concept of ecosystem services. Such information may be useful to promote or enhance dialogue among farmers, scientists and managers.
• 5. These results may contribute to the devising of ecosystem management measures in the Negro River, aimed to conserve both rivers and their associated floodplain forests, involving local fishermen. In the Atlantic Forest, we proposed some initiatives, such as to allow direct economic use of their forests to conciliate conflicting perceptions of farmers about ecological benefits versus economic losses from reforestation. Despite their cultural, environmental and geographical differences, the two study cases are complementary and cost-effective and promising approaches to including LEK in the design of ecological research.

Copyright © 2007 John Wiley & Sons, Ltd.     

Mapping of benthic habitats in northern Safaga Bay (Red Sea,Egypt): a tool for proactive management

1. The spatial distribution of the most important subtidal habitats (coral reefs, coral carpets, seagrass meadows, sand with corals, macroids, mud, hardgrounds) and mangroves was mapped in northern Safaga Bay, Red Sea, Egypt. Coral communities were analysed separately for their ecological and spatial patterns. This, coupled with information about major current patterns in the bay, provides a framework on which to base impact predictions for planned developments or for those already underway. 2. Because the entire shoreline of northern Safaga Bay is earmarked for tourism development, the following impacts have already been observed and can be expected to worsen: dredging, coastal infilling, marina construction, alteration of inshore current patterns as a result of breakwater construction and eutrophication. 3. The maps of habitats could be used by management authorities to either license or forbid these activities in specific areas, thus avoiding damage to sensitive environments. Properly used, resource mapping is a powerful proactive management tool that allows resource managers to anticipate and avoid impacts at an early stage in the process. Copyright © 2000 John Wiley & Sons, Ltd.     

Geophysical approaches to the classification,delineation and monitoring of marine habitats and their communities

• 1. If marine environments are to be systematically protected from the adverse effects of human activities, then identification of the types of marine habitats and the communities they contain, and delineation of their boundaries utilizing a consistent classification is required. Human impacts on defined communities can then be assessed, the ‘health’ of these communities can be monitored, and marine protected areas can be designated as appropriate.
• 2. Schemes to classify habitats at local and regional scales, according to their geophysical properties, may identify different factors as determinants, and/or use them in different sequences in a hierarchical classification. We examined the reasons for these differences in local and regional applications of a global concept, and argue that a common set of factors could be applied in a defined and defensible sequence to produce a common hierarchy of habitat types among geographic regions.
• 3. We show how simple mapping and GIS techniques, based on readily available data, can lead to the identification of representative habitat types over broad geographic regions. We applied a geophysical framework first to the entire Canadian coastline and second to the Scotian Shelf of Atlantic Canada to establish broad scale marine natural regions and ‘seascapes’, respectively. This ecosystem level approach — which defines representative habitat types — is a fundamental prerequisite for many purposes. It can form the basis for further analyses including: definition of community types from habitat — community relationships; evaluation of the potential roles of focal species in marine conservation; evaluation of candidate marine protected areas; definition of unaffected reference areas against which the effects of human activities can be gauged; guidance for water quality monitoring studies; management of marine resources.

Copyright © 2003 John Wiley & Sons, Ltd.     

Effects of fisheries management on fish communities in the floodplain lakes of a Brazilian Amazonian Reserve

Abstract –  We compared fish abundance, diversity and species composition between lakes open (fished) and closed (no-take) to fishing activities in Mamirauá Sustainable Development Reserve in the Central Brazilian Amazon, in order to investigate potential influences of the common-based management. We sampled 1483 fishes from 70 species through gillnet fishing during the low-water season, in seven fished and seven no-take lakes. Contrary to expected, the mean values for abundance, size, diversity and species-richness of fish did not differ between fished and no-take lakes. There was no difference between fished and no-take lakes considering only the abundance of the 14 fish species more intensely targeted by fishermen. However, the abundance of an important commercial fish, the tambaqui ( Colossoma macropomum ) was higher in no-take lakes. Such data from a rapid assessment may be useful to monitor this and other fishery co-management schemes.     

The importance of spatial scales to analysis of fish diversity in Amazonian floodplain lakes and implications for conservation

The Amazon River Basin has the highest fish species diversity of any region in the world, but is under threat from anthropogenic perturbations including overharvesting, alien species and drought. We asked whether species diversity in this region is more a function of within‐lake species richness (i.e., α diversity) or differences among lakes (β diversity). Although many studies have reported on species richness and diversity in single habitats, the importance of measuring diversity at different spatial scales is not yet well established. We collected fish in 10 floodplain lakes along the Solimões River (Brazil), divided evenly between two lake types: those on islands in the river channel (island lakes) and those on the margins of the river (coastal lakes) during 2006. We partitioned fish diversity into three spatial scales: α = within each lake; β₁ = among lakes of the same type (coastal or island) and β₂ = between the two types of lakes, and compared their relative contributions to regional (γ) diversity. β₁ + β₂ contributed as much or more to γ diversity than did α. Although many of the 116 fish species were shared between lake types (S = 72), 32 species were found exclusively in coastal lakes and 12 species were found exclusively in island lakes. Coastal lakes, which were deeper and cooler than island lakes, consistently had higher fish species richness than island lakes. We suggest that it will be necessary to set areas large enough to contain multiple lakes of both types to preserve regional fish diversity.     

Moving beyond fitting fish into equations: Progressing the fish passage debate in the Anthropocene

相似文献   

The application of biogeographical zonation and biodiversity assessment to the conservation of freshwater habitats in Great Britain

1. Twelve biogeographical zones for freshwater habitats in Great Britain were derived, using detrended canonical correspondence analysis of data on climate, relief, geology, soils and land use, in conjunction with occurrence data for more than 300 native freshwater species. 2. The taxonomic groups used were aquatic macrophytes, dragonflies, freshwater molluscs, amphibians and selected leeches, water beetles and crustaceans. The computer database of the Institute of Terrestrial Ecology's Biological Records Centre was used as the principal source of species data. 3. Within each of the 12 biogeographical zones, 10×10 km square ‘hotspots’ for species richness and rarity were identified. 4. The significance of this work for the conservation of freshwater habitats and species in Great Britain is discussed. Copyright © 1999 John Wiley & Sons, Ltd.     

Patterns of fish community composition and biodiversity in riverine fish sanctuaries in Bangladesh: Implications for hilsa shad conservation

Understanding biodiversity and community composition is a prerequisite to sustainable exploitation and conservation of fisheries. We assessed the spatial and seasonal patterns of fish community composition and biodiversity in seasonal no-take riverine sanctuaries in Bangladesh, which aim to conserve the anadromous hilsa shad (Tenualosa spp. and Hilsa keele). Fish samples were collected during monsoon, as well as pre- and postmonsoon, from five sites within two sanctuaries and one site in an open fishing area. Although total abundance was similar along the rivers, species richness was significantly higher at the open fishing site due to its connectivity to nearby habitats. The diversity apparently decreased in a downstream direction. Fish communities at two upstream sites were separated from other sites in multivariate space largely due to higher abundance of hilsa at downstream sites and presence of floodplain-oriented species at the two upstream sites. Short body length and high trophic level at all sites indicated that fish communities were overexploited. Our results also indicated that riverine hilsa sanctuaries in Bangladesh are rich in fish species diversity and support several threatened species designated by the International Union for Conservation of Nature (IUCN). Our study also suggested that since hilsa abundance shapes community patterns, it can therefore impact riverine ecosystem functioning in the sanctuary areas. The findings of this study can serve as an important baseline for future biodiversity assessment, conservation and impact assessment of conservation in rivers, and therefore help to establish multispecies ecosystem-based management of riverine fisheries around the world.     

A review of the biology and status of Cape Fold Ecoregion freshwater fishes

相似文献   

Conservation of migratory fishes in the Amazon basin

1. The Amazon basin hosts the Earth's highest diversity of freshwater fish. Fish species have adapted to the basin's size and seasonal dynamics by displaying a broad range of migratory behaviour, but they are under increasing threats; however, no study to date has assessed threats and conservation of Amazonian migratory fishes.
2. Here, the available knowledge on the diversity of migratory behaviour in Amazonian fishes is synthesized, including the geographical scales at which they occur, their drivers and timing, and life stage at which they are performed.
3. Migratory fishes are integral components of Amazonian society. They contribute about 93% (range 77–99%) of the fisheries landings in the basin, amounting to ~US$436 million annually.
4. These valuable fish populations are mainly threatened by growing trends of overexploitation, deforestation, climate change, and hydroelectric dam development. Most Amazonian migratory fish have key ecological roles as apex predators, ecological engineers, or seed-dispersal species. Reducing their population sizes could induce cascading effects with implications for ecosystem stability and associated services.
5. Conserving Amazonian migratory fishes requires a broad portfolio of research, management, and conservation actions, within an ecosystem-based management framework at the basin scale. This would require trans-frontier coordination and recognition of the crucial importance of freshwater ecosystems and their connectivity.
6. Existing areas where fishing is allowed could be coupled with a chain of freshwater protected areas. Management of commercial and subsistence species also needs fisheries activities to be monitored in the Amazonian cities and in the floodplain communities to allow assessments of the status of target species, and the identification of management units or stocks. Ensuring that existing and future fisheries management rules are effective implies the voluntary participation of fishers, which can be achieved by increasing the effectiveness and coverage of adaptive community-based management schemes.

     

Interactions between the implementation of marine protected areas and right-based fisheries management in Australia

Abstract  The declaration of marine protected areas (MPAs) in Australia generates much confusion and controversy between government conservation and fisheries agencies, the fishing industry and NGOs. There are fundamental differences between the principles and practices underpinning the implementation of MPAs and fisheries management. This paper analyses the interactions between these two approaches to natural resource management and highlights the difficulties in integrating them effectively. The major challenges for governments are: poor cooperation between fisheries and conservation agencies; in principle inconsistencies between allocation of fishing rights by fisheries agencies and loss of these rights through MPA declaration; re-allocation of resources between user groups through spatial zoning; lack of fisheries expertise in conservation planning, and inappropriate single-species/single-issue approach to fisheries management. As fisheries agencies are now considering developing their own MPAs as tools for fisheries management, the need to address inconsistencies between conservation and fisheries approaches to the spatial management of natural resources increases further. Better collaboration between government agencies and better coordination of their activities would help more effective and less conflicting management of marine resources.     

Typology of historical sources and the reconstruction of long‐term historical changes of riverine fish: a case study of the Austrian Danube and northern Russian rivers

Historical data are widely used in river ecology to define reference conditions or to investigate the evolution of aquatic systems. Most studies rely on printed documents from the 19th century, thus missing pre‐industrial states and human impacts. This article discusses historical sources that can be used to reconstruct the development of riverine fish communities from the Late Middle Ages until the mid‐20th century. Based on the studies of the Austrian Danube and northern Russian rivers, we propose a classification scheme of printed and archival sources and describe their fish ecological contents. Five types of sources were identified using the origin of sources as the first criterion: (i) early scientific surveys, (ii) fishery sources, (iii) fish trading sources, (iv) fish consumption sources and (v) cultural representations of fish. Except for early scientific surveys, all these sources were produced within economic and administrative contexts. They did not aim to report about historical fish communities, but do contain information about commercial fish and their exploitation. All historical data need further analysis for a fish ecological interpretation. Three case studies from the investigated Austrian and Russian rivers demonstrate the use of different source types and underline the necessity for a combination of different sources and a methodology combining different disciplinary approaches. Using a large variety of historical sources to reconstruct the development of past fish ecological conditions can support future river management by going beyond the usual approach of static historical reference conditions.     

From endangered to sustainable: Multi‐faceted management in rivers and coasts improves Atlantic salmon (Salmo salar) populations in Denmark

The status of Atlantic salmon, Salmo salar L., over the last decades has been of concern across its entire distribution area. Its anadromous nature exposes the species to human pressures in both freshwater and marine environments, and over long periods, thus exacerbating its decline. Given its value within the food industry, the recreational angling community as well as culturally, the status of Atlantic salmon is regarded as a matter of national and international conservation interest, providing great incentive for its management. The literature currently lacks specific examples of successful and unsuccessful management strategies and practices for Atlantic salmon populations at a broader scale. To address this, the present article describes how the multi‐faceted management approach taken for Danish Atlantic salmon, which included changes in legislation, stocking practices, habitat restoration, population genetics and barrier removals, successfully rehabilitated salmon populations in four major Danish rivers. Specific recommendations are provided for the successful management of Atlantic salmon elsewhere.     

The importance of exposed riverine sediments for phytophagous beetles (Coleoptera) in Scotland and northern England

• 1. The distribution of phytophagous beetle assemblages on exposed riverine sediments (ERS) was investigated using 164 species lists from sites in four river catchments in Scotland and northern England.
• 2. The major influences affecting assemblage distribution were differences in highland and lowland catchment types and within these catchments the amount of vegetation cover. The position of sites within catchments was also important, with differences between tributary and upstream ERS and sites further downstream. Sediment composition had little influence.
• 3. River straightening and impoundments had a significant effect on the distribution of species assemblages.
• 4. A number of nationally rare and scarce species were recorded indicating that ERS appear to be important areas of relatively natural habitat within highly managed landscapes. The habitat diversity of phytophagous assemblages throughout the four catchments differed from that with other beetle groups sampled on the same sites.
• 5. ERS appear to be important sites for phytophagous beetles and the presence of nationally rare and scarce species increases ERS conservation value on sites usually considered important for other invertebrate groups.

Copyright © 2002 John Wiley & Sons, Ltd.     

Challenges in the conservation,rehabilitation and recovery of native stream salmonid populations: beyond the 2010 Luarca symposium

Abstract – In May 2010, I chaired a session on challenges to salmonid conservation at the international symposium ‘Advances in the population ecology of stream salmonids’ in Luarca, Spain. I suggested that in addition to scientific challenges, a major challenge will be improving the links between ecologists, conservationists and policy makers. Because the Luarca symposium focused mainly on ecological research, little time was explicitly devoted to conservation. My objective in this paper is to further discuss the role of ecological research in informing salmonid conservation. I begin with a brief overview of research highlights from the symposium. I then use selected examples to show that ecological research has already contributed much towards informing salmonid conservation, but that ecologists will always be faced with limitations in their predictive ability. I suggest that conservation will need to move forward regardless of these limitations, and I call attention to some recent efforts wherein ecological research has played a crucial role. I conclude that ecologists should take urgent action to ensure that their results are available to inform resource managers, conservation organisations and policy makers regarding past losses and present threats to native, locally‐adapted salmonid stocks.     

Fishes of the Irrawaddy River: Diversity and conservation

1. Few conservation studies have examined fish communities in entire drainage basins, especially in developing regions such as Southeast Asia, one of the most diverse biomes globally. The aim of this study was to establish conservation projections for the whole of the Irrawaddy River system, based on fish diversity patterns, human impact, and environmental change.
2. The Irrawaddy River is one of the five largest rivers in Southeast Asia. Although it has very high diversity of fish species and species endemism, our understanding of resident fish status remains poor.
3. Based on 1,726 field survey and 1,056 database records, 470 fish species and their distribution patterns (i.e. alpha, beta, threatened species, and endemic species diversities) in sub-basins of the Irrawaddy drainage were identified. Canonical correspondence analysis of diversity and environmental patterns indicated that climatic factors had the largest effect on diversity, compatible with the species–energy theory.
4. Fish conservation priorities of sub-basins were evaluated based on diversity patterns and human impact. The delta and Manipur basin regions were highlighted as areas of focus for future fish diversity conservation, and the importance of connectivity in the Irrawaddy main stem was demonstrated.
5. The results of this study will be valuable for future management of the Irrawaddy basin and as a reference for other river basins when implementing protection strategies for fish diversity. This study also advocates the need for systematic investigations across entire drainage basins and further detailed studies on the ecological conditions of poorly studied river systems.

     

GIS analysis reveals the high diversity and conservation value of mollusc assemblages in the floodplain wetlands of the lower Bug River (East Poland)

相似文献   

Variation in fish assemblages across dry-season pools in a Mediterranean stream: effects of pool morphology, physicochemical factors and spatial context

Pires DF, Pires AM, Collares-Pereira MJ, Magalhães MF. Variation in fish assemblages across dry-season pools in a Mediterranean stream: effects of pool morphology, physicochemical factors and spatial context. Ecology of Freshwater Fish 2010: 19: 74–86. © 2009 John Wiley & Sons A/S
Abstract –  Knowledge of patterns of refuge use by fish is critical for maintaining biodiversity in drought-prone streams. In this study, the fish assemblages of 21 dry-season pools in a Mediterranean stream were characterised and related to three sets of factors reflecting pool morphology, physicochemistry and spatial context. Fish were associated with the three sets of variables, with variation partitioning indicating that overall species richness and abundance were primarily related to pool morphology but relative species abundances were mainly associated with physicochemical contexts. In general, species richness was the highest but overall fish abundance was the lowest in large pools. Pools well shaded by riparian canopy held the highest richness and abundance of native fish, but relative species abundances and assembly structure varied among pools contingent on canopy cover, substrate composition and spatial location. These results suggested that conservation of fish diversity in Mediterranean streams requires networks of pools with diverse sizes and physicochemical contexts.     

Seasonal and spatial bank habitat use by fish in highly altered rivers – a comparison of four different restoration measures

Pander J, Geist J. Seasonal and spatial bank habitat use by fish in highly altered rivers – a comparison of four different restoration measures.
Ecology of Freshwater Fish 2010: 19: 127–138. © 2009 John Wiley & Sons A/S
Abstract –  River regulations have resulted in substantial modifications of the characteristics and the diversity of stream ecosystems. Fish habitat use in the context of species life histories and temporal habitat dynamics are crucial for the development of sustainable measures of habitat restoration in degraded rivers. The objective of this study was to compare the effects of introducing four different in-stream structures (bank ripp-rapp, benched bank ripp-rapp, successively grown riparian wood and artificial dead wood, nine replicates each) on the seasonal fish community distribution in a heavily modified stream ecosystem. Species richness and diversity, fish biomass and density showed strong variation (i) between habitat types, (ii) among replicates of the same habitat type, and (iii) in different seasons. The current low abundance of historical widespread rheophilic and migratory fish species in the study stream suggests that technical bank habitat restoration measures are only of limited use for the restoration of highly specialised target species in conservation such as Barbus barbus and Chondrostoma nasus . However, introduction of particular artificial stream structures (in particular of artificial dead-wood fascines) was found to concentrate biomass and density of none-specialised fish species like Squalius cephalus , Alburnus alburnus , Gobio gobio or Rutilus rutilus .     

The ecology of the endemic quillwort Isoëtes malinverniana: From basic research to legal and in situ conservation

1. Scientific publications on the conservation of threatened species can drive practical conservation solutions for endangered species. Yet, a posteriori assessment of the impact of such publications is rarely seen in the scientific literature.
2. The impact of two articles published in Aquatic Conservation: Marine and Freshwater Ecosystems (AQC) on the conservation of the endangered quillwort Isoëtes malinverniana is assessed. The articles were the result of a 10‐year study on the focal species that eventually led to the first reintroduction of I. malinverniana. The first article described the development of a cost‐effective model for the selection of suitable reintroduction sites for the species. The second article provided a summary of the techniques used to reintroduce the species and included techniques of ex situ propagation, recipient site preparation, planting methods, and monitoring.
3. This article reviews the practical conservation actions for I. malinverniana that followed the publication of two AQC papers and how they may affect research and conservation for other quillworts and aquatic macrophytes.
4. The results were surprising and went well beyond the initial expectations of the authors. Both AQC publications stimulated the conservation of I. malinverniana from different points of view. They contributed by informing scientists and policymakers of the risk of extinction of this species, leading to the establishment of a new protected area in Piedmont (northern Italy).
5. Our published data represent a sound starting point for funding opportunities in the context of the European Union LIFE programme. Further impacts include an expansion of knowledge on oligotrophic habitat management, the assessment of conservation status, and the education of the general public, with the last of these greatly enhanced by the two ex situ collections created in the botanic gardens of Tourin and Pavia. Interestingly, other authors are now using our approach in research and conservation on other endemic and endangered quillworts worldwide.