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1.
  • 1. Assemblages of fishes, invertebrates, and macroalgae showed strong and predictable distributional patterns within the newly declared Port Davey marine protected area (MPA) in south‐western Tasmania. Biotic assemblages in the eastern estuarine section of the MPA within Bathurst Channel were extremely anomalous, both in relation to biota elsewhere in the Port Davey region and also to those present along the wider Tasmanian and Australian coasts. Much of this variation was due to the phenomenon of deepwater emergence, with species in 5 m water depth in eastern Bathurst Channel possessing a mean maximum recorded depth of 200 m, compared with<80 m for the same metric when calculated for sites studied elsewhere around Australia. Deepwater emergence in Bathurst Channel was particularly notable for sessile organisms, although also evident among fishes and mobile macro‐invertebrates.
  • 2. Quantitative baseline surveys of reef‐associated species were undertaken at sites interspersed among MPA management zone types and biotic community types, thereby providing an appropriate benchmark for assessing ecological changes in different management zones within the Port Davey region through the long term. Distinctive biota present in eastern and western Bathurst Channel, and eastern Port Davey, are well protected within ‘no‐take’ sanctuary zones; however, a bias in location of sanctuary zones towards areas with little fishery resources resulted in less protection for the western Port Davey biota, which also extends along the open coast. Although the lack of high level protection for sites with fishery resources detracts from conservation goals, the Port Davey MPA nevertheless represents a major advance in environmental protection because the ecologically unique, fully protected locations are a necessary inclusion within any comprehensive Australian MPA network. Copyright © 2009 John Wiley & Sons, Ltd.
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  • 1. Every manager must assess and prioritize anthropogenic impacts on their management area from a long list of threats, but data which allow comparison of the relative ecological impacts of threats for decision‐making is often unavailable.
  • 2. This study employed a systematic and standardized method to collect and quantitatively synthesize expert opinion on the ecological effects of anthropogenic threats to the world's largest marine protected area: the Papahānaumokuākea Marine National Monument (MNM) in the Northwestern Hawaiian Islands (NWHI).
  • 3. In contrast to most threat ranking exercises, the method provides detail on the reasons behind a particular ranking of threats to an area and why the ranking may vary across the ecological landscape.
  • 4. Survey results from 25 experts allowed the comparison of the vulnerability of eight NWHI ecozones to 24 anthropogenic threats in a quantitative manner.
  • 5. Ecozones tended to have distinct top threats: sea‐level rise was identified as the top threat to rocky intertidal, beach and terrestrial ecozones; sea temperature rise was the top threat to the coral reef ecozones; bottom fishing was the top threat to the deep reef/bank ecozone; and pelagic fishing in the wider Pacific was the top threat to the pelagic ecozone owing to impacts on bird, turtle and fish fauna that forage outside the Papahānaumokuākea MNM boundaries.
  • 6. Many of these top threats are difficult for local managers to control because they arise from activities outside the Papahānaumokuākea MNM boundaries, indicating that additional work is needed to preserve the NWHI despite its highly protected status. The analysis indicates where inter‐agency cooperation in removing and mitigating threats should be focused.
Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

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  • 1. Benthic assemblages in the fjord‐like Bathurst Channel estuarine system, south‐western Tasmania, vary over horizontal scales of 1–5 km and vertical scales of 1–10 m. Multivariate analysis indicated a total of eight major assemblages that characterize different sections and depths of the channel.
  • 2. Because tannins in the low‐salinity surface water layer block light, foliose algae reach 5 m depth in the marine western region but do not penetrate below 1 m in the east. By contrast, sessile invertebrates are most abundant below 5 m depth in the west and below 2 m in the east. Deeper assemblages are unlikely to be continuous with assemblages in deeper waters off the Tasmanian coast as they are highly constrained by depth within particular sections of the estuary.
  • 3. While the species composition of the Bathurst Channel biota is most similar to that found elsewhere in Tasmania, the structural character of the biota in terms of major taxonomic groups is more closely allied to that found in fjords of south‐western Chile and south‐western New Zealand. These three regions all possess wilderness settings, high rainfall that is channelled through estuaries as a low‐salinity surface layer, deep‐water emergence of fauna, rapid change in biotic communities over short horizontal and vertical distances, and high levels of local endemism. They also include some of the most threatened aquatic ecosystems on earth due to increasing human activity from a near pristine base, and the potentially catastrophic impacts of climate change. Copyright © 2009 John Wiley & Sons, Ltd.
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  • 1. Fish of the family Galaxiidae are restricted to the southern hemisphere where they occupy a diverse array of habitats ranging from over 2000 m in elevation to sea level. Some species are diadromous and, hence, freshwater, estuarine and marine habitats are used during their life‐cycle; other species complete their entire life‐cycles in freshwater environments.
  • 2. Tasmania has a diverse galaxiid fauna that accounts for 64% of native freshwater fish species found on the island. The Tasmanian galaxiid fauna is characterized by high species richness (5 genera and 16 species), endemism (11 species), restricted distributions, and non‐diadromous life histories (11 species).
  • 3. The galaxiid fauna of Tasmania has significant conservation status with 69% of species considered ‘threatened’. The conservation status of the fauna is recognized at State, national and international levels.
  • 4. The key threats to galaxiids in Tasmania are exotic species, hydrological manipulations, restricted distributions, general habitat degradation and exploitation of stocks.
  • 5. Although work has recently been undertaken to conserve and manage Tasmanian galaxiid populations, the fauna is still thought to be imperilled. Knowledge gaps that need to be addressed include the biology and ecology of most species (e.g. reproductive biology, life histories, habitat use and requirements) and impacts of habitat manipulations, as well as mechanisms and impacts of interactions with exotic species. Techniques to monitor accurately the status of galaxiid species and their populations need to be developed and the coexistence of some galaxiids with introduced salmonids should also be examined.
Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

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  1. A review of the long‐term changes and variations in benthic communities and the current status of the marine invasive species (MIS) in shallow waters of the Yellow Sea (Chinese sector) and the Sea of Japan (Russian and partly Korean sectors) is presented. This paper reflects on the progress and lessons learned, recommending actions for the future about the conservation of biodiversity.
  2. In the Bohai Sea, the benthic ecosystem has been degenerating due to anthropogenic activities such as overfishing and pollution since the 1950s. The dominant position of K‐strategy species is gradually being lost and replaced by R‐strategy species. In the Yellow Sea, the macrobenthic community is different from other areas due to the Yellow Sea Cold Water Mass. Many economic species have been destroyed, and the biotic structure has changed significantly due to overfishing and climate change.
  3. In the Russian sector of the Sea of Japan, the macrobenthic communities in the shallow‐water soft bottom have generally been in a stable condition for the last decades, except for some heavily polluted or disturbed areas due to dredging operations. The abundance of select large invertebrate species has changed considerably due to commercial fishing and poaching. Variations in macro? and meiobenthic communities under aquaculture conditions have occurred on a local scale during the last five decades.
  4. MIS show obvious differences between China and Russia in the following aspects: introduction pathways of MIS, composition and number of non‐native species, threats and impacts of MIS to native communities and ecosystems, and economic and public health impacts.
  5. Long‐term monitoring programmes should be developed to reveal future biotic changes and to separate the effects of cyclic variations of benthic communities from the impacts of pollution and eutrophication. Standardization of sampling procedures is required to compare changes/alternations in benthos across various regions worldwide.
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  1. A high percentage of marine animals produce bioactive compounds that may play a leading role in the discovery of future compounds and drugs of marine origin. However, commercial fishing and other human activities leading to sea warming and pollution may affect these marine animals, even putting them in danger of extinction.
  2. To date, no comprehensive studies have evaluated the conservation status of Mediterranean species with bioactive potential, which is crucial to better understanding of how these species cope with the impacts of human activity.
  3. The study reviewed the bioactive potential and vulnerability of 833 fish and macro-invertebrate species inhabiting the marine protected area of Cap de Creus and surrounding areas. The most active taxa found were Porifera (49 out of 59 species; 83.0%) and Tunicata (17 out of 27 species; 63.0%). The most vulnerable species were Chondrichthyes (eight out of nine species) and Porifera (nine out of 12 species), which together account for over 75% of species classified as such.
  4. Results emphasize the need to introduce specific management measures that protect vulnerable species with bioactive potential as this is a valuable component of marine ecosystems, as well as a potential source of molecules with pharmacological properties beneficial for human health.
  5. Marine protected areas can contribute to preserving marine species of medical interest and achieving their sustainable use in the marine biotechnology industry.
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  • 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   

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  1. Incidental capture by fisheries is one of the principal threats to sea turtles. This study analysed spatial and temporal patterns of sea turtle bycatch, and estimated the direct initial mortality rate of these animals, in the industrial double‐rig‐bottom trawl fishery in south‐eastern Brazil. This is also the first attempt to relate bycatch/at‐sea mortality in bottom trawling to stranded turtles found along the adjacent coast.
  2. The fishery was monitored from October 2015 to April 2018 through data collected voluntarily by the captains of eight industrial double‐rig trawlers. Two hundred and one sea turtles were captured during 9362 tows (43,657.52 trawling hours), resulting in a catch per unit effort (CPUE) of 0.0025 ± 0.0032 turtles h?1 with a standard net of 30.5 m headrope, with no significant difference between the estimated CPUEs for licensed shrimp and demersal fish trawlers.
  3. Caretta caretta (52.24%) and Lepidochelys olivacea (38.81%) were the most frequently captured species. According to Generalized Linear Models, C. caretta bycatch was significantly higher during winter, at lower latitudes (?24° to ?23°) and higher longitudes (?42° to ?40°), while the L. olivacea bycatch was significantly higher at higher latitudes (?23° to ?21°). The direct initial mortality rate of sea turtles in the shrimp trawlers was 7.65 ± 3.85%. However, none of the dead individuals subsequently released with plastic tags (n = 10) were found stranded on the coast. Mortality was not significantly related to the depth or duration of the trawling.
  4. The results of this study suggest the need for improvements to the current management of the bottom trawl fishery in Brazil, moving from a species‐based to a spatial and seasonal‐based approach. There is also a need to develop turtle excluder devices adapted to local fishing conditions.
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