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  • 1. Incidental mortality in fisheries is causing declines in many albatross populations around the world. To assess potential interactions with regional fisheries satellite tags were used to track black-browed albatrosses (Thalassarche melanophrys) and light-mantled sooty albatrosses (Phoebetria palpebrata) breeding on Heard Island during the chick-rearing periods of 2003/04. This was the first time individuals from either population had been tracked.
  • 2. Black-browed albatrosses foraged largely within the Heard and McDonald Islands Economic Exclusion Zone (EEZ) north-east of the island, although 20% of foraging trips were to areas north of the EEZ into Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) areas 58.5.1 and 58.5.2 and into the Îles Kerguelen EEZ.
  • 3. In contrast, the light-mantled sooty albatrosses foraged well south of Heard Island along the southern boundary of the Antarctic Circumpolar Current. Both species appear to face minimal risk of incidental mortality during the chick-rearing period in the regulated, legal fisheries, but are threatened by illegal, unreported and unregulated (IUU) fishing vessels operating in the southern Indian Ocean.
Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

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Knowledge about the areas used by the foraging wandering albatross, Diomedea exulans, its prey and overlap with longline fisheries is important information not only for the conservation of this species but also for furthering our understanding of the ecology of its prey. We attached satellite‐tracking devices and activity recorders to wandering albatrosses between May and July of 1999 and 2000 (years of differing food availability around South Georgia) in order to assess inter‐annual variation in the main foraging areas, association with oceanographic features (i.e. fronts, bathymetry), diet and interactions with fisheries. The overall foraging patterns of the tracked birds were similar in 1999 and 2000, ranging between southern Brazil (28°S) and the Antarctic Peninsula (63°S) and between the waters off Tristan da Cunha (19°W) and the Patagonian Shelf and oceanic waters south of Cape Horn (68°W) in the South Atlantic. In 1999, wandering albatrosses spent most time in sub‐Antarctic oceanic waters, their trip durations were significantly longer and they fed on fish and cephalopods (53 and 42% by mass, respectively). In contrast, in 2000, they spent more time in Antarctic waters, foraging trips were shorter and the diet was predominantly fish (84% by mass). Wandering albatrosses were associated with the sub‐Antarctic Front (SAF; both years), Subtropical Front (STF; in 1999) and the Tropical Front (TF; in 2000) suggesting that this species exploits prey concentrated at oceanic fronts. Fisheries discards also seemed to provide a very good source of food. Several fish species that are targeted (e.g. Patagonian toothfish, Dissostichus eleginoides) or are available as offal/discards from commercial fisheries (e.g. the macrourids, Antimora rostrata and Macrourus holotrachys) were mainly associated with the South Georgia shelf and the Patagonian Shelf, respectively. Wandering albatross foraging areas overlapped with longline fisheries in three different regions: around South Georgia, at the Patagonian Shelf and in oceanic waters north of 40°S. Females commuted more frequently to the Patagonian Shelf and to oceanic areas where longline fisheries were operating. Males, on the other hand, spent more time on the shelf/shelf slope of South Georgia where they were more at risk from the local Patagonian toothfish fishery, particularly in 2000. These results emphasize that inter‐annual variation in foraging preferences could lead to increased incidental mortality of this vulnerable species. Potential evidence for this is provided by a satellite‐tracked wandering albatross (male; 1.8‐day trip), whose diet contained a Patagonian toothfish head and a longline hook, and who spent extensive time in the water (44% of the time wet; 0.3 days of the trip) where a Patagonian toothfish longline fishing vessel was operating.  相似文献   

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  1. Marine protected areas (MPAs) are becoming a widely used tool for the conservation of biodiversity and for fishery management; however, most of these areas are designed without prior knowledge of the basic ecological aspects of the species that they are trying to protect.
  2. This study investigated the movement of two top predators: the Galapagos shark, Carcharhinus galapagensis, and the yellowtail amberjack, Seriola lalandi, in and around the Motu Motiro Hiva Marine Park (MMHMP) using MiniPAT satellite tags to determine the effectiveness of this MPA for the protection of these species.
  3. The Galapagos sharks (n = 4) spent most of their tag deployment periods inside the MMHMP. However, high intraspecific variability was observed in their movement dynamics. Daily individual maximum movements ranged from 17 to 58 km and the maximum distance from Salas y Gómez Island, the only emergent island within the MMHMP, ranged from 31 to 139 km.
  4. The maximum linear distance travelled for a female juvenile Galapagos shark (152 cm total length) was 236 km, which is greater than the maximum distance previously documented for juveniles of this species (<50 km).
  5. For the yellowtail amberjack (n = 1), 91% of the satellite geolocations were within the MMHMP, with a maximum daily distance travelled of 6 km. The maximum distance travelled between points was 111 km and the maximum distance from Salas y Gómez Island was 62 km.
  6. All archival tagged fish spent most of their time at depths of <50 m and never left the epipelagic zone. Daytime versus night-time differences were pronounced in all individuals but showed high interindividual variability.
  7. This study provides a baseline on the movement of these two top predators in the MMHMP and provides valuable insights for the creation of MPAs in the region and elsewhere.
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  • 1. Marine protected areas (MPAs) range from multiple‐use areas (MUA) to absolute no‐take reserves (NTR). Despite their importance for fisheries management, there are few long‐term studies comparing benefits from different types of MPAs within the same region.
  • 2. Fish assemblages were monitored for five years (2001–2005) in the largest coral reefs in the South Atlantic (Abrolhos Bank, Brazil). Monitoring included one community‐based MUA, two NTRs (one established in 1983 and another in 2001), and one unprotected area. Benthic assemblages at these areas, as well as fish assemblages on unprotected deeper reefs (25–35 m), were monitored from 2003 onwards.
  • 3. Habitat characteristics strongly influenced fish assemblages' structure. This, together with the lack of data from before establishment of the MPAs, did not allow an unequivocal analysis of the effects of the MPAs.
  • 4. Biomass of commercially important fish, particularly small carnivores, was higher in the older NTR. Biomass of black grouper Mycteroperca bonaci increased by 30‐fold inside NTRs during the study period, while remaining consistently low elsewhere.
  • 5. A single herbivore species, the parrotfish Scarus trispinosus, dominated fish assemblages (28.3% of total biomass). Biomass of this species increased in 2002 on the younger NTR and on the MUA, soon after establishment of the former and banning of the parrotfish fishery in the latter. This increase was followed by a decline from 2003 onwards, after increased poaching and reopening of the parrotfish fishery.
  • 6. Fish biomass increased in 2002 across the entire region. This increase was stronger in sites closer to deeper reefs, where fish biomass was up to 30‐times higher than shallow reefs: movement of fish from deeper to shallower areas may have played a role.
  • 7. The effective use of MPAs in the Abrolhos Bank is still dependent on adequate enforcement and the protection of critical habitats such as deep reefs and mangroves.
Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

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  • 1. The decision to designate, implement and manage marine protected areas (MPAs) is often made ad hoc without clear guiding procedures. This study evaluates the process of establishment and management of MPAs in temperate soft‐bottom marine areas, including identification of objectives, site selection, designation, implementation, ecological effectiveness and socio‐economic impacts.
  • 2. For the first time, literature about marine conservation strategies in soft‐bottom temperate areas is brought together in one ‘systems approach’, which is visualized in a flow chart including three phases: setting policy objectives, making decisions and evaluating the eventual effects of the MPA. Policy objectives are generally easy to identify and in most cases national policy objectives are driven by international and regional legal obligations. The decision making process is the most complex phase, as the acceptance of MPAs has to be balanced against the human activities that take place in the area.
  • 3. The relation between fisheries and MPA‐management appears to be most challenging in soft‐bottom temperate marine areas because of conflicting interests and institutional differences. Activities limited in space and not relying directly on ecosystem functions (e.g. offshore energy production and aggregate extraction) are generally easier to manage than fisheries.
  • 4. The conceptual mapping exercise presented here serves as a basis for a systems approach for MPAs and has been tested for the Belgian coastal environment. In the Belgian ‘MPA‐process’, the application of the systems approach proves to be useful in providing insight into the complex interactions of various authorities with scattered jurisdictions.
  • 5. The unified and simplified representation of the various aspects is (1) a useful communication tool for policy makers and managers to inform other sectors and the public at large and (2) a valuable support during the ‘MPA‐process’ that considerably enhances the prospects for success.
Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

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  • 1. The aim was to determine the status of subtidal rocky benthic assemblages in three marine protected areas (MPAs) of the Canary Islands: (1) La Graciosa; (2) Mar de Las Calmas; (3) La Palma. Sea urchin (Diadema aff. antillarum) populations and non‐crustose macroalgal cover were surveyed, and used as an indicator of conservation status in the three MPAs as well as in a highly fished area (HFA‐Tenerife Island).
  • 2. Comparing characteristics between each MPA and the HFA, and considering issues of management and design, it was concluded that the three MPAs each have a different conservation status. ‘Mar de Las Calmas’ marine reserve was found to have the most desirable conservation status, followed by ‘La Palma’ marine reserve based on sea urchin populations and non‐crustose macroalgae assemblages.
  • 3. Conversely, ‘La Graciosa’ had the highest density of D. aff. antillarum and the lowest cover of non‐crustose macroalgae out of the three MPAs. Values were comparable to those at the HFA, which shows ‘La Graciosa’ to have the undesired conservation status.
  • 4. Different spatial distribution patterns of non‐crustose macroalgal as well as different algal composition cover were observed between the three MPAs and the HFA. These differences were principally attributed to the intensity of grazing activity of the key herbivore D. aff. antillarum. It is suggested that the different study areas correspond to different phase shifts that imply differing resilience of systems that should be taken into a count in future conservation strategies.
Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

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  1. This study evaluated management effectiveness in three marine protected areas (MPAs) for conservation of the Antillean manatee (Trichechus manatus manatus Linnaeus 1758), located on the eastern coast of the Yucatan Peninsula, Mexico. The MPAs evaluated were the Yum‐Balam Flora and Fauna Reserve, Sian Ka'an Biosphere Reserve, and Chetumal Bay Manatee Sanctuary. The extent of the traditional, popular, and scientific manatee knowledge and research were assessed, as well as the prescribed conservation management actions, relevant stakeholders, and the degree of inclusion of manatee species in the management schemes of these MPAs.
  2. Four general criteria, 12 specific criteria, and 62 indicators were developed. In total, 199 interviews were completed in seven communities of the MPAs in order to determine the perception of the social, economic, and conservation impacts of the manatee and its management.
  3. Although the evaluated MPAs were not wholly comparable among themselves due to their different management categories and schemes, administration, socio‐economic context, and the dynamics and conflicts encountered, a comparison was conducted using standardized criteria and a categorical scale in order to evaluate the level of effectiveness of each MPA.
  4. The MPA with the highest management effectiveness in manatee conservation was found to be the Chetumal Bay, with an effectiveness classed as good (71%), followed by Sian Ka'an with intermediate effectiveness (53%) and Yum‐Balam, also with intermediate effectiveness (43%).
  5. The relationships between the key stakeholders of the three MPAs and economic activities such as fishing and tourism are the factors that most influence the effectiveness of management for manatee conservation.
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