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1.
Abstract: Underwater trails are intended as interpretative tools in marine parks, but concentrating divers and snorkelers in defined areas may negatively affect the surrounding environment. We examined spatial and temporal patterns in the effects of use of underwater trails on coral reef flats in the Great Barrier Reef Marine Park, Australia. Changes in benthic assemblages were assessed on two new trails used by snorkelers, two unused (control) trails, and two undisturbed areas. Total percent coral cover, numbers of broken colonies, and living coral fragments were counted 6 months before and 6 months after the new trails began to be used. Spatial patterns of effects around concentrated nodes of use were determined by stratified sampling around and away from the interpretative signs within each trail. Despite comparatively low levels of use (approximately 15 snorkelers per trail per week), snorkelers caused significant damage to corals along the trails. Branching corals (non- Acropora branching corals and Millepora spp.) were most affected. More damage occurred near the interpretative signs than elsewhere on the trails. The numbers of broken branches and damaged coral colonies in the snorkeling trails increased rapidly but stabilized within 2 months of the commencement of use. There was no significant change in overall benthic assemblages within the trails after 6 months of use by snorkelers. Although concentrating snorkelers within confined trails caused increased damage to corals, the effects can be mitigated by appropriate design and placement of the trails and by managing the behavior of snorkelers. Interpretative information should warn users about the damage they may cause when swimming along the trails. Managing the behavior of snorkelers in the water is likely to be more effective in reducing damage than simply applying fixed limits to the amount of use the trails receive.  相似文献   

2.
Empirical data quantifying the long-term movement patterns of coral reef top predators are needed in order to design marine protected areas (MPAs) that will provide these fishes with effective, long-term protection. Acoustic telemetry was used to quantify the movements of a large coral reef top predator (Aprion virescens, Lutjanidae; Hawaiian name ‘uku’) at five atolls in the Northwestern Hawaiian Islands Marine National Monument (NWHIMNM) from May 2005 to September 2006. The study atolls were located between 23.8°N, 166.2°W and 28.5°N, 178.3°W, and were separated from their nearest receiver-equipped neighbor by distances ranging from 100 to 478 km. No inter-atoll movements by uku were detected but individuals were seasonally site-attached to core activity areas of up to 12 km in length, and ranged up to 19 km across atolls. Within their core areas, tagged uku exhibited diel and tidal habitat shifts, with the latter resulting in round trips of up to 24 km in 24 h. Seasonal uku migrations resulted in extended winter (October–April) absences from summer (May–September) core activity areas and may be linked to summer spawning. Large MPAs (i.e., entire islands, atolls or banks) would probably be required for full protection of resident populations of adult uku, but such ‘island-scale’ MPAs will not benefit fisheries unless there is significant larval supply from MPAs to neighboring fished areas, or adult emigration over time scales exceeding the 16-month monitoring period of this study. A mixed management strategy of combining smaller MPAs with conventional measures (e.g., minimum size limits, catch, and effort restrictions) may be the best approach for sustaining uku fisheries. However, this would still require relatively large MPAs (12 km in length) to contain uku short-term (diel and tidal) movements, and seasonal migrations would still take uku beyond the boundaries of MPAs of this size. These fluxes across MPA boundaries could supply fish to fisheries but, if high exploitation rates exist, fishing could eliminate key MPA benefits such as increased numbers of large, highly fecund individuals. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

3.
Marine protected areas (MPAs) are the cornerstone of most marine conservation strategies, but the effectiveness of each one partly depends on its size and distance to other MPAs in a network. Despite this, current recommendations on ideal MPA size and spacing vary widely, and data are lacking on how these constraints might influence the overall spatial characteristics, socio‐economic impacts, and connectivity of the resultant MPA networks. To address this problem, we tested the impact of applying different MPA size constraints in English waters. We used the Marxan spatial prioritization software to identify a network of MPAs that met conservation feature targets, whilst minimizing impacts on fisheries; modified the Marxan outputs with the MinPatch software to ensure each MPA met a minimum size; and used existing data on the dispersal distances of a range of species found in English waters to investigate the likely impacts of such spatial constraints on the region's biodiversity. Increasing MPA size had little effect on total network area or the location of priority areas, but as MPA size increased, fishing opportunity cost to stakeholders increased. In addition, as MPA size increased, the number of closely connected sets of MPAs in networks and the average distance between neighboring MPAs decreased, which consequently increased the proportion of the planning region that was isolated from all MPAs. These results suggest networks containing large MPAs would be more viable for the majority of the region's species that have small dispersal distances, but dispersal between MPA sets and spill‐over of individuals into unprotected areas would be reduced. These findings highlight the importance of testing the impact of applying different MPA size constraints because there are clear trade‐offs that result from the interaction of size, number, and distribution of MPAs in a network.  相似文献   

4.
Abstract:  Theoretical models of marine protected areas (MPAs) that explore benefits to fisheries or biodiversity conservation often assume a dynamic pool of fishing effort. For instance, effort is homogenously distributed over areas from which subsets of reserves are chosen. I tested this and other model assumptions with a case study of the multiple-use Jervis Bay Marine Park. Prior to zoning of the park I conducted 166 surveys of the park's recreational fisheries, plotting the location of 16,009 anglers. I converted these plots into diagrams of fishing effort and analyzed correlates between fishing and habitat and the effect of two reserve designs—the draft and final zoning plans of the park—on the 15 fisheries observed. Fisheries were strongly correlated with particular habitats and had negatively skewed and often bimodal spatial distribution. The second mode of intensely fished habitat could be 6 SD greater than the fishery's mean allocation of effort by area. In the draft-zoning plan, sanctuary zone (no-take) area and potential subduction of fishing effort were similar. In the final plan, which was altered in response to public comment, the area of sanctuary zone increased, and the impact on fishing effort decreased. In only one case was a fishery's most intensely targeted location closed to fishing. Because of the discriminating manner with which fishers target habitats, if simple percentage targets are used for planning, sanctuary location can be adjusted to avoid existing fishing effort. According to modeled outcomes, the implication of this may be diminished reserve effectiveness. To address this, reserve area should be implicitly linked to subducted fishing effort when promoting or modeling MPAs.  相似文献   

5.
Large marine protected areas (MPAs) of unprecedented size have recently been established across the global oceans, yet their ability to meet conservation objectives is debated. Key areas of debate include uncertainty over nations’ abilities to enforce fishing bans across vast, remote regions and the intensity of human impacts before and after MPA implementation. We used a recently developed vessel tracking data set (produced using Automatic Identification System detections) to quantify the response of industrial fishing fleets to 5 of the largest MPAs established in the Pacific Ocean since 2013. After their implementation, all 5 MPAs successfully kept industrial fishing effort exceptionally low. Detected fishing effort was already low in 4 of the 5 large MPAs prior to MPA implementation, particularly relative to nearby regions that did not receive formal protection. Our results suggest that these large MPAs may present major conservation opportunities in relatively intact ecosystems with low immediate impact to industrial fisheries, but the large MPAs we considered often did not significantly reduce fishing effort because baseline fishing was typically low. It is yet to be determined how large MPAs may shape global ocean conservation in the future if the footprint of human influence continues to expand. Continued improvement in understanding of how large MPAs interact with industrial fisheries is a crucial step toward defining their role in global ocean management.  相似文献   

6.
Abstract:  Seahorses (  Hippocampus ) live in tropical and temperate waters. Habitat degradation and fishery overexploitation have led to drastic population declines on a global scale. Population monitoring is therefore essential to determine current status and manage conservation. In this first study in Italian waters on the geographic and ecological distribution of the two Mediterranean species, Hippocampus hippocampus and Hippocampus ramulosus , recreational scuba divers were recruited and trained to report sightings. A specially formulated questionnaire was produced and distributed to scuba diving schools and centers. In the 3-year study, 2536 divers spent 6077 diving hours gathering data and completed 8827 questionnaires. Eight percent of the questionnaires showed seahorse sightings, for a total of 3061 sighted specimens, 68% of which referred to Hippocampus ramulosus . The two species had overlapping geographic distributions. Seahorse abundance varied, with the northern Adriatic Sea showing greatest abundance, followed by the central-southern Tyrrhenian Sea. Seahorses were rare in the Ligurian and northern Tyrrhenian seas. Preferred habitats were shallow areas with either sandy bottoms or Posidonia oceanica (L.) Delile meadows. Seahorse distribution may be correlated with the degree of degradation of P. oceanica meadows. Resource users (the divers) were willing to take part in biological monitoring and contributed in scientific terms by collecting considerable amounts of data over short time periods and in economic terms by decreasing costs. The greatest limitation with volunteers was the difficulty in obtaining a uniformly distributed sample across time and space. We conclude that recreational divers and other resource users can play an active part in monitoring the marine environment and that the Mediterranean Hippocampus Mission may be used as a model for biodiversity monitoring.  相似文献   

7.
This study examined the relative impacts of different human activities and natural resource protections on the spatial distribution of beach vegetation and related habitat features (wrack, dune succession) in New Jersey (USA). Field surveys of the 209-km shoreline categorized beach segments according to vegetation cover classes, human activities, protection measures (exclosures, beach management plans, access restrictions) and ownership status (federal, state, etc.). A partition model (classification tree) was used to confirm the relative dominance hierarchy of human actions on the distribution of beach vegetation observed, and quantitative comparisons of dominant activities were conducted using vegetation data collected on 218 transects. The spatial extent of beach vegetation was found to be severely restricted by human activities when unconstrained by resource protections. The greatest reductions were found to result from mechanical raking (?99 %), scraping (?91 %) and all-year recreational ORV use (?86 %), which were dominant on nearly 70 % of the state shoreline. Beaches containing larger areas of vegetation (>5 m) were concentrated in areas with resource protections of various kinds (99 %), and on federal or other public parklands (68 %). Exclosures resulted in the greatest coverage of vegetation (48 % of beach surface) compared to public access restricted areas (41 %), beach management plans (31 %), government-only ORV use (31 %), and off-season recreational ORVs (15 %). Greater protection and recovery of beach vegetation and habitat is needed for species conservation and erosion protection in New Jersey and other coastal environments where these activities occur.  相似文献   

8.
Abstract: Social, economic, and ecological criteria contribute to the successful design, implementation, and management of marine protected areas (MPAs). In the context of California's Marine Life Protection Act Initiative, we developed a set of methods for collecting, compiling, and analyzing data about the spatial extent and relative economic importance of commercial and recreational fishing. We interviewed 174 commercial fishers who represented the major fisheries in the initiative's north‐central coast region, which extends from Point Arena south to Pigeon Point. These fishers provided data that we used to map the extent of each of the fishing grounds, to weight the relative importance of areas within the grounds, to characterize the operating costs of each fishery, and to analyze the potential economic losses associated with proposed marine protected areas. A regional stakeholder group used the maps and impact analyses in conjunction with other data sets to iteratively identify economic and ecological trade‐offs in designations of different areas as MPAs at regional, port, and fishery extents. Their final proposed MPA network designated 20% of state waters as MPAs. Potential net economic loss ranged from 1.7% to 14.2% in the first round of network design and totaled 6.3% in the final round of design. This process is a case study in the application of spatial analysis to validate and integrate local stakeholder knowledge in marine planning.  相似文献   

9.
Abstract: The establishment of marine protected areas is often viewed as a conflict between conservation and fishing. We considered consumptive and nonconsumptive interests of multiple stakeholders (i.e., fishers, scuba divers, conservationists, managers, scientists) in the systematic design of a network of marine protected areas along California's central coast in the context of the Marine Life Protection Act Initiative. With advice from managers, administrators, and scientists, a representative group of stakeholders defined biodiversity conservation and socioeconomic goals that accommodated social needs and conserved marine ecosystems, consistent with legal requirements. To satisfy biodiversity goals, we targeted 11 marine habitats across 5 depth zones, areas of high species diversity, and areas containing species of special status. We minimized adverse socioeconomic impacts by minimizing negative effects on fishers. We included fine‐scale fishing data from the recreational and commercial fishing sectors across 24 fisheries. Protected areas designed with consideration of commercial and recreational fisheries reduced potential impact to the fisheries approximately 21% more than protected areas designed without consideration of fishing effort and resulted in a small increase in the total area protected (approximately 3.4%). We incorporated confidential fishing data without revealing the identity of specific fisheries or individual fishing grounds. We sited a portion of the protected areas near land parks, marine laboratories, and scientific monitoring sites to address nonconsumptive socioeconomic goals. Our results show that a stakeholder‐driven design process can use systematic conservation‐planning methods to successfully produce options for network design that satisfy multiple conservation and socioeconomic objectives. Marine protected areas that incorporate multiple stakeholder interests without compromising biodiversity conservation goals are more likely to protect marine ecosystems.  相似文献   

10.
Ecotourism often is promoted as an ecologically sustainable activity, but some ecotourism activities negatively impact coastal ecosystems. Impacts of intensive diving tourism on coral reefs remain poorly understood, especially in the Florida Keys. We determined patterns of recreational dive frequency, diver behaviour, and coral damage on reefs near Key Largo, and assessed how pre-dive briefings and other factors affect these damage rates. Recreational divers contacted live stony corals ~ 18 times per scuba dive; most contacts deposited sediment onto corals, but also caused abrasion to coral tissues and fracture of coral skeletons. Divers who received pre-dive ecological briefings caused significantly less coral damage than those who did not, and divers with cameras and/or gloves caused the most damage. The proportion of damaged corals increased significantly with the estimated rate of recreational diving on each reef, and the percent cover of live corals decreased. We conclude that current rates of recreational diving in Key Largo are unsustainable, resulting in damage to >80 % of coral colonies and reduction of live coral cover to <11 % at heavily-dived sites. We recommend that dive tour operators administer pre-dive ecological briefings to all recreational divers, provide extra briefings to camera and glove users, and employ underwater dive guides who intervene when divers inadvertently damage live stony corals. This study provides a scientific basis to support management of intensive ecotourism on Florida coral reefs.  相似文献   

11.
Fishery managers must understand the dynamics of fishers and their prey to successfully predict the outcome of management actions. We measured the impact of a two-day exclusively recreational fishery on Caribbean spiny lobster in the Florida Keys, USA, over large spatial scales (>100 km) and multiple years and used a theoretical, predator-prey functional response approach to identify whether or not sport diver catch rates were density-independent (type I) or density-dependent (type II or III functional response), and if catch rates were saturated (i.e., reached an asymptote) at relatively high lobster densities. We then describe how this predator-prey framework can be applied to fisheries management for spiny lobster and other species. In the lower Keys, divers exhibited a type-I functional response, whereby they removed a constant and relatively high proportion of lobsters (0.74-0.84) across all pre-fishing-season lobster densities. Diver fishing effort increased in a linear manner with lobster prey densities, as would be expected with a type-I functional response, and was an order of magnitude lower in the upper Keys than lower Keys. There were numerous instances in the upper Keys where the density of lobsters actually increased from before to after the fishing season, suggesting some type of "spill-in effect" from surrounding diver-disturbed areas. With the exception of isolated reefs in the upper Keys, the proportion of lobsters removed by divers was density independent (type-I functional response) and never reached saturation at natural lobster densities. Thus, recreational divers have a relatively simple predatory response to spiny lobster, whereby catch rates increase linearly with lobster density such that catch is a reliable indicator of abundance. Although diver predation is extremely high (approximately 80%), diver predation pressure is not expected to increase proportionally with a decline in lobster density (i.e., a depensatory response), which could exacerbate local extinction. Furthermore, management actions that reduce diver effort should have a concomitant and desired reduction in catch. The recreational diver-lobster predator-prey construct in this study provides a useful predictive framework to apply to both recreational and commercial fisheries, and on which to build as management actions are implemented.  相似文献   

12.
The success of marine protected areas (MPAs) as a tool for conservation and fisheries management has been well documented. However, these results have typically been seen in shallow water systems and questions remain whether this management strategy could be successfully applied to deepwater ecosystems. Our objectives were to determine the efficacy of four deepwater MPAs called bottomfish restricted fishing areas (BRFAs), with various time spans of protection, monitored at depths between 90 and 310 m from 2007 to 2011 for six species of deepwater snapper and one grouper harvested in the Main Hawaiian Islands. Our results suggested that the duration of protection influenced reserve effects, particularly for target species. Mean fish length, and in some cases abundance, increased for one or more of the most economically important target species inside nearly all tested BRFAs. In addition, more mature fish were seen inside the BRFA with the longest duration of protection (~14 years); species richness increased outside this area while inside it remained the same. Here, we provide the first evidence that deepwater MPAs can have positive effects on deepwater species and that many protection effects were consistent with results found in shallow water ecosystems. While these findings are novel, additional data over greater temporal scales will be necessary to determine whether these trends will continue and if others will become important over time.  相似文献   

13.
Disturbance plays an important role in structuring marine ecosystems, and there is a need to understand how conservation practices, such as the designation of Marine Protected Areas (MPAs), facilitate postdisturbance recovery. We evaluated the association of MPAs, herbivorous fish biomass, substrate type, postdisturbance coral cover, and change in macroalgal cover with coral recovery on the fringing reefs of the inner Seychelle islands, where coral mortality after a 1998 bleaching event was extensive. We visually estimated benthic cover and fish biomass at 9 sites in MPAs where fishing is banned and at 12 sites where fishing is permitted in 1994, 2005, 2008, and 2011. We used analysis of variance to examine spatial and temporal variations in coral cover and generalized additive models to identify relations between coral recovery and the aforementioned factors that may promote recovery. Coral recovery occurred on all substrate types, but it was highly variable among sites and times. Between 2005 and 2011 the increase in coral cover averaged 1%/year across 21 sites, and the maximum increase was 4%/year. However, mean coral cover across the study area (14%) remained at half of 1994 levels (28%). Sites within MPAs had faster rates of coral recovery than sites in fished areas only where cover of macroalgae was low and had not increased over time. In MPAs where macroalgae cover expanded since 1998 there was no recovery. Where coral was recovering on granite reefs there was a shift in relative prevalence of colony life‐form from branching to encrusting species. This simplification of reef structure may affect associated reef fauna even if predisturbance levels of coral cover are attained. Efecto de la Expansión de Macroalgas y Áreas Marinas Protegidas sobre la Recuperación de Coral Después de una Perturbación Climática  相似文献   

14.
This study investigates the vehicle damage caused by recreational use on three coastal dune systems on the west coast of Ireland. Using aerial photographs taken in 1973, 2000, 2004 and 2006 in conjunction with ecological surveys, the impacts of recreational activities were assessed. The results show that the overall area of tracks increased more than threefold between 1973 and 2007 with the exception of one site where restricted access resulted in a subsequent reduction in the number of tracks. The study further shows that most recreational activities at the sites were water-based, with most traffic movement directed towards the shore and the highest density of tracks being within the first few hundred meters of the High Water Mark. The results of this study are discussed in the context of visitor management strategies for coastal conservation sites under recreational pressure.  相似文献   

15.
Marine reserves can help in maintaining biodiversity and potentially be useful as a fishery management tool by removing human-mediated impacts. Intertidal, soft-sediment habitats can often support robust recreational and commercial shellfish harvests, especially for clams; however, there is limited research on the effects of reserves in these habitats. In San Juan County, Washington, several reserves prohibit recreational clam digging. We examined the effects of these reserves on infaunal community composition through comparison with non-reserve beaches during a 6-week period. Clam abundance, overall species richness and total polychaete family richness were greater on reserve beaches compared to non-reserve beaches. Additionally, an experiment within a reserve demonstrated negative impacts of digging on non-target infauna. These effects probably resulted from local disruption and disturbance of the sediment habitat and not from increased post-digging predation, which was controlled. Intertidal reserves could play an important role in sustaining local and potentially regional biodiversity.  相似文献   

16.
Abstract:  Ecosystem-scale networks of marine protected areas (MPAs) are important conservation tools, but their effectiveness is difficult to quantify in a time frame appropriate to species conservation because of uncertainties in the data available. The dugong ( Dugong dugon ) is a mobile marine species that occurs in shallow inshore waters of an ecosystem-scale network of MPAs (the Great Barrier Reef World Heritage Area [GBRWHA]). We developed a rapid approach to assess risk to dugongs in the region and evaluate options to ameliorate that risk. We used expert opinion and a Delphi technique to identify and rank 5 human factors with the potential to adversely affect dugongs and their sea grass habitats: netting, indigenous hunting, trawling, vessel traffic, and poor-quality terrestrial runoff. We then quantified and compared the distribution of these factors with a spatially explicit model of dugong distribution. We estimated that approximately 96% of habitat of high conservation value for dugongs in the GBRWHA is at low risk from human activities. Using a sensitivity analysis, we found that to decrease risk, commercial netting or indigenous hunting had to be reduced in remote areas and the effects of vessel traffic, terrestrial runoff, and commercial netting had to be reduced in urban areas. This approach enabled us to compare and rank risks so as to identify the most severe risks and locate specific sites that require further management attention.  相似文献   

17.
Abstract: Marine protected areas (MPAs) are a popular conservation strategy, but their impacts on human welfare are poorly understood. To inform future research and policy decisions, we reviewed the scientific literature to assess MPA impacts on five indicators of human welfare: food security, resource rights, employment, community organization, and income. Following MPA establishment, food security generally remained stable or increased in older and smaller MPAs. The ability of most fishing groups to govern MPA resources changed. Increased resource rights were positively correlated with MPA zoning and compliance with MPA regulations. Small sample sizes precluded statistical tests of the impacts of MPAs on employment, community organization, and income. Our results demonstrate that MPAs shape the social well‐being and political power of fishing communities; impacts (positive and negative) vary within and among social groups; and social impacts are correlated with some—but not all—commonly hypothesized explanatory factors. Accordingly, MPAs may represent a viable strategy for enhancing food security and empowering local communities, but current practices negatively affect at least a minority of fishers. To inform policy making, further research must better document and explain variation in the positive and negative social impacts of MPAs.  相似文献   

18.
D. Zavodnik 《Marine Biology》1987,94(2):265-269
In the Adriatic Sea, the spatial distribution and aggregation aspects of swarning Pelagia noctiluca (Forskål, 1775) were studied by SCUBA divers from August 1984 to November 1985. Medusae were asually distributed in the upper 20- to 30-m layer. Dense aggregations caused by wind, currents and tidal phenomena occurred only in shallow coastal waters. Maximum population densities of swarms drifting freely near the shore were estimated at about 20 individuals per cubic meter, but when they had drifted ashore jellyfish could reach concentrations of 150 to 600 individuals in the same volume of sea water. Some peculiar forms of aggregations could be distinguished: couples, clusters, and surface and bottom aggregations. The effects of wind, currents and geomorphological features of the shore on passive aggregations of jellyfish are presented.  相似文献   

19.
Abstract: Quantifying the extent to which existing reserves meet conservation objectives and identifying gaps in coverage are vital to developing systematic protected‐area networks. Despite widespread recognition of the Philippines as a global priority for marine conservation, limited work has been undertaken to evaluate the conservation effectiveness of existing marine protected areas (MPAs). Targets for MPA coverage in the Philippines have been specified in the 1998 Fisheries Code legislation, which calls for 15% of coastal municipal waters (within 15 km of the coastline) to be protected within no‐take MPAs, and the Philippine Marine Sanctuary Strategy (2004), which aims to protect 10% of coral reef area in no‐take MPAs by 2020. We used a newly compiled database of nearly 1000 MPAs to measure progress toward these targets. We evaluated conservation effectiveness of MPAs in two ways. First, we determined the degree to which marine bioregions and conservation priority areas are represented within existing MPAs. Second, we assessed the size and spacing patterns of reserves in terms of best‐practice recommendations. We found that the current extent and distribution of MPAs does not adequately represent biodiversity. At present just 0.5% of municipal waters and 2.7–3.4% of coral reef area in the Philippines are protected in no‐take MPAs. Moreover, 85% of no‐take area is in just two sites; 90% of MPAs are <1 km2. Nevertheless, distances between existing MPAs should ensure larval connectivity between them, providing opportunities to develop regional‐scale MPA networks. Despite the considerable success of community‐based approaches to MPA implementation in the Philippines, this strategy will not be sufficient to meet conservation targets, even under a best‐case scenario for future MPA establishment. We recommend that implementation of community‐based MPAs be supplemented by designation of additional large no‐take areas specifically located to address conservation targets.  相似文献   

20.
Analysis of the biological traits (e.g., feeding mode and size) that control how organisms interact with their environment has been used to identify environmental drivers of, or impacts on, species and to explain the importance of biodiversity loss. Biological trait analysis (BTA) could also be used within risk-assessment frameworks or in conservation planning if one understands the groups of traits that predict the sensitivity of habitats or communities to specific human activities. Deriving sensitivities from BTA should extend sensitivity predictions to a variety of habitats, especially those in which it would be difficult to conduct experiments (e.g., due to depth or risk to human life) and to scales beyond the norm of most experiments. We used data on epibenthos, collected via video along transects at 27 sites in a relatively pristine region of the seafloor, to determine scales of natural spatial variability of derived sensitivities and the degree to which predictions of sensitivity differed among 3 stressors (extraction of species, sedimentation, and suspended sediments) or were affected by underlying community compositions. We used 3 metrics (weighted abundance, abundance of highly sensitive species, and number of highly sensitive species) to derive sensitivity to these stressors and simulated the ability of these metrics to detect a range of stressor intensities. Regardless of spatial patterns of sensitivities across the sampled area, BTA distinguished differences in sensitivity to different stressors. The BTA also successfully separated differences in community composition from differences in sensitivity to stressors. Conversely, the 3 metrics differed widely in their ability to detect simulated impacts and likely reflect underlying ecological processes, suggesting that use of multiple metrics would be informative for spatial planning and allocating conservation priorities. Our results suggest BTA could be used as a first step in strategic prioritization of protected areas and as an underlying layer for spatial planning.  相似文献   

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