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1.
  • 1. Conservation efforts have traditionally been directed to ‘flagship’ species (whales, seals, migratory birds, etc.) that capture public attention. Often these flagship species occupy distinctive habitats. Distinctive habitats appear to be distinguished because of anomalous physical structures and unique oceanographic processes occurring within them, whereas representative habitats are not notable in this way. Distinctive habitats are found in areas of various physical anomalies described primarily by temperature, chlorophyll and topography.
  • 2. Several different kinds of distinctive habitats can be defined by their anomalous physical structures and oceanographic and biological processes. Species diversity may be either higher or lower in distinctive than in representative habitats. Distinctive habitats predominantly belong to a class of environments called ‘ergoclines’, and are typically associated with elevated resources at some ‘trophic level’.
  • 3. These elevated resources may be either the product of true production (i.e. they are generated (in situ), or they are the product of physical accumulation due to circulation mechanisms. These processes lie at the heart of the ecology of distinctive habitats, and are fundamental to maintenance of ecosystem health, ecological integrity, distributions, abundances and recruitment of species, patterns of animal migrations, and potential or actual fisheries yields.
  • 4. Conservation strategies need to examine the relationships between distinctive and representative habitats and species diversity. A strategy, leading from studies on flagship or other focal species, could have several advantages. It should rejuvenate the inherent appeal and significance of ‘species’ approaches to marine conservation, provide a rationale for human interest and a new foundation for examination of marine ecological interactions. It would also require a novel synthesis of relationships between ‘species’ and ‘spaces’ approaches to marine conservation by asking how we can take the best advantage of both approaches, rather than seeing them as in conflict.
Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

2.
  • 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   

3.
  • (1) Assessing species diversity is a basic requirement for conservation, and protecting biodiversity is a major goal of marine area conservation.
  • (2) A case study is presented on the development of a literature‐based (1870s to 2000), museum collection‐based, georeferenced inventory of marine invertebrate species of the Haida Gwaii (Queen Charlotte Islands) region, Canada.
  • (3) Database structure and quality assurance are described, along with including indigenous people's words for species towards using traditional knowledge within cooperative marine conservation area management.
  • (4) The utility of this type of inventory is proposed as a starting point for gathering regional biodiversity knowledge, and facilitating addition of other knowledge types, towards marine area conservation.
Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

4.
  • 1. The use of surrogate species (i.e. keystones, indicators, umbrellas) has been advocated for the conservation of target taxa and communities.
  • 2. A recent Habitat Conservation Plan, which provided conservation measures intended to protect multiple aquatic species of concern over a large area, established an important precedent for surrogate species in aquatic conservation pursuant to the US Endangered Species Act.
  • 3. The Habitat Conservation Plan's application of federally threatened bull trout was evaluated as an umbrella species for westslope cutthroat trout, which is in decline but not listed under the Act. Approximately 75% of known westslope cutthroat trout strongholds are not captured within bull trout strongholds west of the continental divide. The Habitat Conservation Plan failed to evaluate the suitability of this umbrella species and consequently failed to cover important priority areas for westslope cutthroat trout conservation.
  • 4. This case study highlights the feasibility and importance of formally validating assumptions of surrogate species utility in multi‐species conservation planning.
Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

5.
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9.
  • 1. Recent approaches to the planning of marine protected area (MPA) networks for biodiversity conservation often stress the need for a representative coverage of habitat types while aiming to minimize impacts on resource users. As typified by planning for the Australian South‐east Marine Region, this strategy can be manipulated by political processes, with consequent biased siting of MPAs. Networks thus created frequently possess relatively low value for biodiversity conservation, despite significant costs in establishment and maintenance.
  • 2. Such biases can be minimized through application of the data‐driven and species‐based concept of key biodiversity areas (KBAs).
  • 3. By mapping locations of threatened species and populations that are highly aggregated in time or space, the KBA process allows marine sites of global biodiversity significance to be systematically identified as priority conservation targets. Here, the value of KBAs for marine conservation planning is outlined, and guidelines and provisional criteria for their application provided.
Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

10.
  1. Detecting rare species is often a necessity for conservation and management, yet challenging for many field survey methods. Environmental DNA (eDNA) is a highly promising solution that has been shown to outperform many established survey methods.
  2. Macquarie perch (Macquaria australasica) is an endangered native species that has declined significantly in range and abundance. Detection of M. australasica was compared with an abundant alien fish species (Oncorhynchus mykiss) using eDNA and three conventional survey methods: gill nets, electrofishing and fyke nets.
  3. eDNA occupancy estimates for both fish species were compared using four different models to investigate what effect these differences have on false positives and false negatives for the rare and common fish species. These models used unadjusted eDNA detections in water samples, eDNA detections that have been screened using a limit of detection method to remove potential false positives, eDNA data supplemented with a second survey method, or eDNA data augmented with sequencing of positive polymerase chain reaction replicates.
  4. eDNA surveying as a single detection method was found to be more efficient and sensitive compared with each capture method separately and combined. Occupancy estimates for the common and rare species did not vary significantly between the four site occupancy-detection models, suggesting that supplementary data may not have as much effect on occupancy estimates compared with other approaches such as temporal or spatial sampling.
  5. We conclude that eDNA outperforms the three established survey methods for both a rare and common freshwater fish species. Although there was no significant effect of augmenting eDNA survey methods with other survey data, additional data may improve confidence in detection, and provide confirmatory evidence for unexpected or new detections of a species.
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11.
  • 1. The lack of information about marine biodiversity is problematic for the selection of conservation reserves that aim to protect representative samples of biodiversity. A number of surrogate measures for biodiversity have been suggested as a potential solution to this problem.
  • 2. The present study tested the effectiveness of using higher taxa of macroinvertebrates as a surrogate for species‐level identification to depict spatial variation in species richness and assemblage variation and to select conservation reserves in one estuary in south‐east Australia.
  • 3. Spatial patterns of richness and assemblage variation for species were significantly correlated with patterns defined from genera, families, orders, classes, and phyla with a decline in the magnitude of correlation coefficients from finer to coarser resolutions. A network of reserves selected to include representatives of all phyla, classes, orders, families and genera coincidentally included 54%, 61.7%, 75%, 92.6%, 98.8% species in 8.3%, 13.9%, 17.7%, 44.4% and 58.3% of grid cells, respectively. However, only reserves selected for genera, families and orders performed significantly better than random selection.
  • 4. Percentage of species represented by orders, families and genera in a realistic level of available grid cells for conservation (i.e. 13.9%) were very close ranging between 70 and 73.5%. A factor diminishing the performance of order as surrogate for species richness was related to the difficulty of identifying many macroinvertebrates to the order level. Therefore, it is concluded that genus‐ and family‐level identification is an effective surrogate for species‐level identification for conservation planning in estuaries.
Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

12.
13.
  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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14.
Local fisher knowledge is an important source of information for the adjustment of environmental baselines relative to anthropogenic impacts on marine ecosystems. This knowledge is also susceptible to the shifting baseline syndrome. Four generations of fishers neighbouring a marine park in Eastern Brazil, were surveyed regarding the conservation status of nine reef fish species. Shifts in environmental baselines were detected among fisher generations. Fishers older than 50 years not only caught larger individual fish, but catches of large fish occurred four decades ago, suggesting that bigger fish are in decline in the region. Of nine reef fish species, seven exhibited significant declining catch trends based on information provided by fishers. Such declining status was not reported by all informants of younger generations, so the ability to identify such species increases significantly with fisher age. The fish species most cited as overexploited were Mycteroperca bonaci (Poey), Epinephelus morio (Valenciennes) and Ocyurus chrysurus (Bloch), emphasising that special attention should be given to the management and conservation of these species in Eastern Brazil. These results also showed that knowledge acquired by elder fishers (> 50 years old) can provide valuable insights into the conservation status of reef fish and the adjustment of environmental baselines for proper management of a marine park.  相似文献   

15.
  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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16.
  • 1. Four macroalgal, four macroinvertebrate and eight fish species were surveyed at eight sites (three inside, five outside the proposed reserve) over three years before the establishment of the Taputeranga Marine Reserve (MR) on Cook Strait (Wellington, New Zealand). This baseline data set was used to estimate temporal and spatial variability in size and abundance of these taxa, and will be used to quantify taxon‐specific changes in size and abundance once the MR is established.
  • 2. Statistically significant differences in size and/or abundance were observed for many taxa among the sites. These differences are consistent with the existence of a natural environmental gradient from the west (entrance to Cook Strait) to the east (Wellington Harbour). This gradient highlights the importance of conducting a pre‐reserve baseline survey at multiple sites and over multiple years to better understand the conservation or fisheries benefits that MRs are expected to deliver.
  • 3. Two macroalgal, one macroinvertebrate, and six fish species showed statistically significant seasonal variation in abundance. Subsequent multi‐taxa monitoring needs to include a seasonal component to capture this natural variability.
  • 4. This multi‐site and multi‐year data set represents one of the most comprehensive and robust baseline data sets available anywhere in the world. It will be used to quantify the ecological changes associated with a newly established full no‐take marine reserve. Ongoing monitoring will enhance understanding of the sizes and abundances of key taxa, allow a detailed determination of the conservation effects of reserve establishment, and inform management decisions for Wellington's south coast.
Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

17.
Minimising the unintended capture of fish, marine mammals, reptiles, seabirds and other marine organisms is an important component of responsible fisheries management and for stabilising declines and rebuilding populations of threatened species. The analyses presented were designed to establish the first quantitative baseline of historical catches, catch rates and species composition for the dominant tuna fisheries operating in the western and central Pacific, the world's largest in terms of tuna catch. Using records from 612,148 fishing events collected by independent ‘at sea’ observers, estimates for finfish, billfish, elasmobranchs, marine mammals and sea turtles show that the composition and magnitude of catches varied considerably by fishery type and practice for the period 2003–2019. Simulations indicated that precision in longline estimates would be improved by monitoring a proportion of fishing sets from all fishing trips rather than full coverage from a proportion of all fishing trips. While attributing reasons for temporal trends in estimated bycatch was difficult due to the confounding impacts of changing abundances and fishing practices, the trends identified the nature of potential relationships for species that are not accurately quantified, or not covered, by fishing vessel logbooks. The trends in catch estimates, and the catch rate models, have utility in identifying species which may require targeted additional analyses and management interventions, including species of conservation interest (either due to their threatened status or vulnerability to fishing) such as elasmobranchs and sea turtles. Moreover, the estimates should support future evaluations of the impact of these industrial-scale fisheries on bycatch species.  相似文献   

18.
Marine ecosystem management has traditionally been divided between fisheries management and biodiversity conservation approaches, and the merging of these disparate agendas has proven difficult. Here, we offer a pathway that can unite fishers, scientists, resource managers and conservationists towards a single vision for some areas of the ocean where small investments in management can offer disproportionately large benefits to fisheries and biodiversity conservation. Specifically, we provide a series of evidenced‐based arguments that support an urgent need to recognize fish spawning aggregations (FSAs) as a focal point for fisheries management and conservation on a global scale, with a particular emphasis placed on the protection of multispecies FSA sites. We illustrate that these sites serve as productivity hotspots – small areas of the ocean that are dictated by the interactions between physical forces and geomorphology, attract multiple species to reproduce in large numbers and support food web dynamics, ecosystem health and robust fisheries. FSAs are comparable in vulnerability, importance and magnificence to breeding aggregations of seabirds, sea turtles and whales yet they receive insufficient attention and are declining worldwide. Numerous case‐studies confirm that protected aggregations do recover to benefit fisheries through increases in fish biomass, catch rates and larval recruitment at fished sites. The small size and spatio‐temporal predictability of FSAs allow monitoring, assessment and enforcement to be scaled down while benefits of protection scale up to entire populations. Fishers intuitively understand the linkages between protecting FSAs and healthy fisheries and thus tend to support their protection.  相似文献   

19.
  1. Most MPA networks are designed only with ecological processes in mind to increase their conservation utility. However, since MPA networks often involve large geographic areas, they also affect and involve multiple actors, institutions, and policy sectors.
  2. A key challenge when establishing an effective MPA network is to align the ‘social system’ with the biophysical MPA network (the ‘ecological system’). This challenge is often denoted as ‘social–ecological fit’.
  3. Facilitating collaborative social interactions among various actors and stakeholders (social connectivity) is equally as important as accomplishing ecological connectivity. New analytical approaches are required to effectively examine this ‘social’ dimension of fit.
  4. An emerging marine reserve network in Jamaica and the recent invasion of Indo‐Pacific lionfish are used as a case study to: (1) examine the extent to which horizontal and vertical social ties bring local and national actors together to collaborate, coordinate, and share knowledge; and (2) assess the extent to which different attributes and features of such multilevel social networks may enhance or inhibit particular aspects of social–ecological fit.
  5. Findings suggest that multilevel linkages have played the greatest role in relation to enhancing fit in the marine reserve network in the context of the recent lionfish invasion. However, the long‐term propensity of the multi‐actor and multilevel networks to enhance social–ecological fit is uncertain given the prevalence of weak social ties, lack of a culture of information sharing and collaboration, and limited financial resources.
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20.
  • 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   

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