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1.
  1. Based on optimal foraging theory, animals are expected to maximize foraging benefits whilst minimizing risks. Despite risking being subjected to anthropogenic impacts such as water contamination, marine traffic, and underwater noise, estuaries have been identified as the preferred habitat of the Indo‐Pacific humpback dolphin (Sousa chinensis, IPHD). However, it remains unclear why this vulnerable species favours such risky habitats.
  2. Here, an exploratory case study in Zhanjiang estuary, China, was conducted to test the hypothesis that IPHDs select estuarine habitats as a trade‐off that maximizes foraging opportunities whilst minimizing the risk of mortality.
  3. The results showed that IPHDs accept greater mortality risks for higher food rewards but select habitats with lower risks when food rewards are similar between two locations.
  4. Although this type of information is important for underpinning models for individual dolphins, its principal role is to show environmental protection agencies why IPHDs favour estuaries despite the increased mortality risks.
  5. Habitat conservation plans should carefully consider prey stocks, possibly through the presence of marine protected areas near estuaries, as local overfishing may lead vulnerable cetacean populations to take greater risks.
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2.
  1. Most of the world's nations adopted the 20 Aichi global biodiversity targets to be met by 2020, including the protection of at least 10% of their coastal and marine areas (Target 11) and the avoidance of extinction of threatened species (Target 12). However, reconciling these biodiversity targets with socio‐economic demands remains a great dilemma for implementing conservation policies.
  2. In this paper, Aichi Targets 11 and 12 were simultaneously addressed using Brazil's exclusive economic zone as an example. Priority areas for expanding the current system of marine protected areas within the country's eight marine ecoregions were identified with data on threatened vertebrates under different scenarios. Additionally, the potential effects of major socio‐economic activities (small? and large‐scale fishing, seabed mining, and oil and gas exploration) on the representation of conservation features in proposed marine protected areas were explored.
  3. Areas selected for expanding marine protected areas solely based on biodiversity data were different (spatial overlap from 62% to 93%) from areas prioritized when socio‐economic features were incorporated into the analysis. The addition of socio‐economic data in the prioritization process substantially decreased opportunity costs and potential conservation conflicts, at the cost of reducing significantly (up to 31%) the coverage of conservation features. Large? and small‐scale fisheries act in most of the exclusive economic zone and are the major constraints for protecting high‐priority areas.
  4. Nevertheless, there is some spatial mismatch between areas of special relevance for conservation and socio‐economic activities, suggesting an opportunity for reconciling the achievement of biodiversity targets and development goals within the intricate Brazilian seascape by 2020 and beyond.
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3.
  1. The characterization of benthic communities at the Burdwood Bank slope (≥200 m depth) is provided, comprising data from the marine protected area (MPA) Namuncurá II (created in December 2018), as well as from some deep bathyal surrounding areas in the Southwest Atlantic Ocean. This information was acquired during two research cruises with RV Puerto Deseado (Argentina) during 2016 and 2017.
  2. Marine animal forests were detected in the study area: coral gardens, mainly composed of alcyonaceans, were detected in the south and west of Burdwood Bank (MPA Namuncurá II) and neighbouring areas, whereas pennatulacean aggregations were detected in the north‐west of the plateau. The three‐dimensional structures of live but also dead corals provide substrate and refuge to many associated species. Benthic communities dominated by sponges were also recorded between 200 and 300 m in depth.
  3. Six sites that meet the characteristics of vulnerable marine ecosystems (VMEs) are reported.
  4. Conservation strategies applied to scarcely known austral Argentinean waters led to the establishment of a pioneer MPA (Namuncurá I). Following the management plan that aimed to establish the biodiversity of Namuncurá I and neighbouring areas, the area of protection has now been enlarged to include the southern slope of the bank (currently Namuncurá II), where marine animal forests were detected, at depths below 200 m. The data presented here provide empirical evidence to support the conservation value of the region.
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4.
  1. Despite significant progress made in Chile, and globally, in establishing marine protected areas (MPAs), the actual contribution to marine biodiversity conservation needs to be revised, to focus on representativeness and the diversity of tools alongside effective implementation, management, and enforcement.
  2. This study makes progress in this direction, describing the most recent advances in marine conservation in Chile and analysing the contribution of the different conservation instruments as well as the distribution of designated areas across ecoregions. Furthermore, it examines the potential contribution of alternative area-based instruments to balance ocean protection. The advances observed in Chile were compared among four South American countries and five leading countries in ocean conservation, analysing protection levels in coastal areas, continental exclusive economic zones, and overseas territories.
  3. Data on MPA boundaries and attributes were sourced from the World Database on Protected Areas and complemented the official information on MPAs and territorial user rights for fisheries and for indigenous people in South America.
  4. The current level of protection in Chile is among the highest in the world in area coverage and in the proportion of the continental exclusive economic zone assigned to fully protected areas. However, it exhibits the strongest imbalances in the distribution of designated MPAs between coastal and oceanic waters, in comparison with the leading countries and also within South America (Perú, Chile, Argentina, and Uruguay), and among ecoregions.
  5. The patterns observed suggest that Chile has advanced, but concentrated, conservation efforts in low-threat, remote ecoregions. There is an urgent need to progress towards high-threat ecoregions, which implies balancing the needs of nature and people. The distribution of ancillary conservation instruments can help double the level of protection in threatened coastal areas, filling gaps in marine conservation and creating an opportunity to progress and diversify conservation strategies.
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5.
  • 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.  相似文献   

6.
  1. Evidence-based decisions relating to effective marine protected areas as a means of conserving biodiversity require a detailed understanding of the species present. The Caribbean island nation of St Lucia is expanding its current marine protected area network by designating additional no-take marine reserves on the west coast. However, information on the distribution of fish species is currently limited.
  2. This study used baited remote underwater stereo-video to address this shortcoming by investigating the effects of depth and seabed habitat structure on demersal fish assemblages and comparing these assemblages between regions currently afforded different protection measures.
  3. From the 87 stations visited a total of 5,921 fish were observed comprising 120 fish taxa across 22 families. Species richness and total abundance were higher within the highly managed region, which included no-take reserves. Redundancy analysis explained 17% of the total variance in fish distribution, driven predominantly by the seabed habitats. The redundancy analysis identified four main groups of demersal fishes each associated with specific seabed habitats.
  4. The current no-take marine reserves protected two of these groups (i.e. fishes associated with the ‘soft corals, hard corals or gorgonians’ and ‘seagrass’ groups). Importantly, habitats dominated by sponges, bacterial mats, algal turfs or macroalgae, which also supported unique fish assemblages, are not currently afforded protection via the marine reserve network (based on the five reserves studied). These results imply that incorporation of the full breadth of benthic habitat types present would improve the efficacy of the marine reserve network by ensuring all fish assemblages are protected.
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7.
8.
9.
  • 1. The Galapagos Marine Reserve provides refuge for numerous threatened marine species, including 16 mammals, birds, reptiles and fish currently recognized on the 2006 IUCN Red List of Threatened Species, plus an additional 25 endemic fish, mollusc, crustacean, echinoderm, coral and macroalgal species that comply with threatened species criteria because of declining extent of occurrence or highly‐localized ranges, and hence also qualify for inclusion on the Red List.
  • 2. Threatened marine species with restricted ranges are not randomly distributed across the archipelago but tend to co‐occur at a limited number of sites that are predominantly located in the west. Sites at which threatened species are known to persist, particularly those with a large proportion of the global population, are here identified as sites of global conservation significance — key biodiversity areas.
  • 3. The majority (27) of the 38 inshore key biodiversity areas identified are currently protected from fishing because they lie within the 17% of coastal waters that is zoned as ‘no‐take’ tourism or conservation zones. All key biodiversity areas should be protected from extractive exploitation if threatened species are to be safeguarded. This can be achieved, at the minimum, through a relatively minor amendment to the existing marine zoning scheme, whereby an additional 2% of the coastline is dedicated to conservation.
Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

10.
  1. The implementation of marine protected areas (MPAs) has been widely used as a tool to manage and conserve marine resources and services. Yet, to date, the reserve effect is still weakly evaluated, particularly for soft-sediment habitats.
  2. The Arrábida MPA, considered as a biodiversity hotspot, was fully established in 2009 on the west coast of Portugal and is characterized by large expanses of soft-sediment habitats. This MPA was established to protect biodiversity and to ensure the livelihood of the local small-scale fisheries community.
  3. Beyond before–after-control–impact (BACI) analyses were carried out on catch data (abundance and biomass) of 351 trammel net sets from experimental fishing campaigns (2007–2019) to study the reserve effect on demersal fish populations.
  4. The results show a declining trend in abundance inside and outside the protected area, with significant positive effects only found for undersize commercial species and Solea senegalensis, and a general increase in fish species total length. Despite the lack of any obvious reserve effect, the increase in fish length can be considered as a first sign.
  5. Anthropogenic pressures are generalized around the area, and transgressions of the restrictions are frequently observed inside the no-take zone. These can, among other aspects, delay or prevent the expected reserve effects. Therefore, enforcement and/or modification of the spatial plan must be incentivized to achieve the goals of the MPA.
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11.
  1. The present study originated with the expansion of the boardwalk within the urban and port area of Manzanillo, México. Prior to civil works related to the placement of tetrapods, surveys of potential sites for the relocation of benthic organisms in alternative areas were carried out.
  2. Based on indicators of the physical–chemical environment and biotic factors, nine areas with potential for relocation were evaluated. The areas of greatest potential were associated with environments located away from the influence of the port environment.
  3. A total of 13,559 benthic organisms belonging to 68 species associated with three main substratum types (rocky, sandy, and mixed) were collected. There were no differences in the ecological indices between the three substrata.
  4. The proximity of the collection area to the influence of port traffic and sources of pollution associated with the physical environment could be an important factor that affects ecological indices and the reduction in the abundance of some protected species and species of commercial interest.
  5. The success of collection and relocation processes depends on minimizing possible errors, especially during transportation, when overcrowding, handling, and damage resulting from variable physico‐chemical conditions should be avoided.
  6. Through a scheme of actions based on ecological principles, management actions, and civil engineering technology, it was possible to carry out mitigation, conservation, and habitat improvement actions in coastal marine environments exposed to anthropogenic impacts.
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12.
  • 1. The relentless increase in both human activities and exploitation of marine resources is a threat to marine habitats and species.
  • 2. For marine systems, several protection initiatives have been outlined over the past decade to significantly reduce the current rate of biodiversity loss at global, regional, and national levels, and to establish representative networks of marine protected areas with the aim of protecting 10–30% of marine habitats.
  • 3. Reliable estimates of the total area occupied by each habitat are crucial to set adequate protection initiatives. Habitat mapping requires a sound habitat classification. Many classification schemes have been developed in different areas of the world, sometimes based on questionable criteria.
  • 4. A critical analysis of the most recent marine habitat classification list produced for the Mediterranean Sea from the Regional Activity Centre for Specially Protected Areas (RAC/SPA) showed that (i) 39% of habitats and associated species considered in the list are scarcely covered by scientific knowledge from Web‐based resources; (ii) 62% of the species/genera included in the list are primary producers; (iii) quantitative information about the geographical distribution of selected habitats and associated species is scant; and (iv) when available, information is largely unbalanced and biased towards the shallow western Mediterranean Sea.
  • 5. Improved inventories of marine habitats are needed to support accurate and consistent mapping activities. The combination of large‐scale mapping and sound habitat classifications will allow better estimates of biodiversity distribution, to reverse regional/global habitat loss rates through the achievement of conservation targets and deadlines that, for the moment, are systematically not met. Copyright © 2011 John Wiley & Sons, Ltd.
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13.
14.
  • 1. Focal species warrant conservation attention because they serve keystone, umbrella, indicator or flagship functions, and/or are sensitive or vulnerable to threats.
  • 2. Defining critical habitat requirements for viable populations of focal species could provide important information for marine protected area (MPA) network design, as a complement to other considerations such as habitat representation.
  • 3. A generally applicable approach for selecting focal species based on 20 characteristics that identify species as important in the community and/or susceptible to threats is presented with reference to the Scotia–Fundy region of Atlantic Canada.
  • 4. Although a rigorous quantitative assessment of all local species against these characteristics is not included, several potential focal species are shown to possess many of the characteristics.
  • 5. The North Atlantic right whale (Eubalaena glacialis) demonstrates flagship, umbrella and indicator characteristics, and is locally vulnerable to threats. Seasonally important feeding, nursery and socializing areas could be protected within a network of MPAs in the Scotia–Fundy region, which would concurrently protect sympatric species with smaller area requirements.
  • 6. Cold‐water corals (i.e. Primnoa resedaeformis, Paragorgia arborea, Lophelia pertusa) possess keystone, indicator and flagship characteristics and are sensitive and vulnerable to local threats; thus, areas of high coral density and/or diversity could be protected within an MPA network, which would also help protect associated species.
  • 7. These examples illustrate how consideration of the characteristics can help identify focal species and how their life requisites may be applied to MPA network design.
  • 8. Rigorous quantitative assessment of all local species is required to select a comprehensive suite of focal species, and further research is needed to fill data gaps and confirm underlying hypotheses.
  • 9. Nonetheless, focal species considerations show promise as a complement to other approaches to MPA network design and thus warrant further exploration in the Scotia–Fundy region and elsewhere.
Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

15.
  1. Marine ecosystems are highly affected by several human stressors. In this context, beyond passive restoration measures such as the creation of marine protected areas, it is urgent that we explore active restoration measures to enhance and accelerate the recovery of sessile marine species.
  2. Bryozoans are among the most common sessile invertebrates in rocky bottom ecosystems and are considered habitat‐forming species that are highly vulnerable to physical disturbances, such as recreational diving, ghost fishing nets, and global warming, which makes them highly vulnerable to other impacts. Despite their ecological importance and vulnerability, to date restoration actions for bryozoans have rarely been explored.
  3. In this study, different restoration techniques were developed and tested, with a focus on two types of effective methodologies previously applied to other marine invertebrates: recruitment enhancement and the transplantation of adult colonies, in both cases using the Mediterranean bryozoan Pentapora fascialis as a model species.
  4. First, different types of artificial surfaces were installed in different coralligenous habitats to test the enhancement of recruitment, concluding that plastic grids are the best substrate in terms of facilitating the recruitment of new bryozoan colonies.
  5. Second, different methodologies were tested for adult transplantation. The most successful was to fix colonies to a suitable substrate with a nylon thread attached to the colony ex situ (i.e. on the boat).
  6. Using this technique a trial restoration programme was undertaken, involving transplanting adult colonies collected from a ghost fishing net trapped on the bottom, which showed a high survival rate of ~50% after 6 months.
  7. The low economic cost of the implementation of the proposed techniques as well as the successful results obtained highlight the viability of restoring bryozoan populations over long temporal and spatial scales.
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16.
  • 1. As the interest of divers in exploring marine protected areas grows, so does their impact on sensitive marine organisms and communities. This situation has led managers to adopt a variety of measures to manage scuba diving in marine reserves. However, if marine areas need to be managed and protected from the adverse effects of human activities, then the characterization of marine habitats and the communities they contain, along with the potential effects of scuba diving, will need to be evaluated on scientific lines.
  • 2. To this end, the use of benthic mapping, together with an evaluation of community vulnerability, constitutes a complementary tool for managing scuba diving, as is demonstrated in the present study.
  • 3. The identification and evaluation of the different communities observed in Cabo de Palos‐Islas Hormigas Marine Reserve enables managers to propose different measures for controlling potential diver impact and also for evaluating the effects of these measures, thus reducing the degradation of the benthic organisms and communities, benefiting the local tourism industry and allowing a more sustainable use of the marine reserve resources.
Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

17.
  1. A spatial approach to coastal management, such as marine protected areas, is being increasingly used to address biodiversity and fishery declines resulting from habitat loss, degradation, and overfishing. This approach is especially applicable in regions and fisheries that are data poor, and which often lack regulations and adequate capacity for enforcement. In data-poor situations, species that have economic, cultural, and charismatic value can provide leverage for ecosystem protection.
  2. In this study, acoustic telemetry was used to confirm a pre-spawning aggregation site, acting as critical information for protection of essential habitat for bonefish. Additionally, data sharing with an acoustic telemetry study on smalltooth sawfish (Pristis pectinata) documented linkages between the pre-spawning aggregation site and bonefish home ranges ≥70 km distant, thus providing an estimate of the catchment area.
  3. These data provided post hoc support for a marine national park designated in 2002, and demonstrate that the park is of the appropriate spatial scale.
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18.
19.
  1. Scutellastra mexicana is the largest known patellid limpet species and probably is one of the most endangered marine invertebrates.
  2. The species was once distributed along the American Pacific coast from Mexico to Peru, but their large size (up to 35 cm long) and easy accessibility (shallow sublittoral), made it very vulnerable to human collection and now is extinct on most of the mainland Mexican coast.
  3. In August 2017, a large population of this species was found on María Cleofas island, off the coast of west‐central Mexico (Marías Archipelago, Pacific Ocean). This constitutes the only report of a population of this species since 1988.
  4. A total of 808 adult individuals of up to 26 cm in length and 20 cm in width were estimated, together with the presence of juveniles, suggesting that it is a self‐sustaining population. The population was monitored in August 2017 and August 2018.
  5. Although the species is under the category ‘Special Protection’ in the General Mexican Wild Law, and that María Cleofas island is a Biosphere Reserve, fishermen that operate with impunity in the area decimated the limpet population within a year of its discovery. Abundance in the shallowest area decreased significantly from 120 individuals per transect (65 m long and 2.75 m wide) in August 2017 to 48 individuals in August 2018, and the estimated adult population decreased from 808 to 304 limpets.
  6. Neither passive national conservation policies nor local practices have reduced current threats to biodiversity and resource depletion in Marías Archipelago. Protected areas like this are ‘paper parks’—parks in name only—because there is no active conservation strategy or protection of marine species.
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20.
  1. This paper describes the tensions between the legal requirements for conservation and the most beneficial biological practice for mobile transnational marine species, using the harbour porpoise (Phocoena phocoena) in European Atlantic waters as a case study.
  2. Harbour porpoise are the smallest and one of the most abundant cetaceans occurring throughout the European continental shelf waters, and are affected by human activities occurring in the same waters, especially certain fishing activities.
  3. The Convention on the Conservation of European Wildlife and Natural Habitats (the Bern Convention) and its implementing legislation the Council Directive on the Conservation of Natural Habitats and of Wild Fauna and Flora 92/43/EEC (i.e. the Habitats Directive) are the main legal drivers for species conservation throughout the European Union. They aim for the long-term achievement of favourable conservation status and make provision for the use of two conservation measures: protected areas and strict protection measures. The strict protection measures aim to ensure that all forms of deliberate killing are prevented, and that where incidental killing and capture occurs, it does not have a negative effect on conservation status.
  4. The conservation of harbour porpoise is currently dependent upon tackling the key issue of bycatch in fisheries. However, in challenges to Member States on their application of the Habitats Directive, the European Commission has chosen to focus on site designation rather than the implementation of the strict protection measures required to monitor and, where necessary, reduce bycatch.
  5. This tension between a legal focus on the designation of protected areas instead of tackling threats such as bycatch has potentially led to negative conservation consequences for harbour porpoise and, in part, may explain why wider marine biodiversity has continued to deteriorate in Europe.
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