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Mingming Liu Lars Bejder Mingli Lin Peijun Zhang Lijun Dong Songhai Li 《水产资源保护:海洋与淡水生态系统》2020,30(2):364-374
- Place‐based management can be an effective conservation tool to protect cetaceans from anthropogenic pressures. The spatial use of the world's second largest population of the threatened Indo‐Pacific humpback dolphins (Sousa chinensis) is not well‐documented, which makes it challenging to designate protected areas for this population.
- To address this knowledge gap and to test the efficacy of an existing dolphin protected area (Zhanjiang Leizhou Bay Municipal Humpback Dolphin Nature Reserve, ZLBMHDNR), boat‐based surveys were conducted to document dolphin occurrence from 2015 to 2018, covering an area of 1221 km2 in the eastern waters off Zhanjiang, China. In total, 253 dolphin group sightings were obtained during 174 survey days.
- Spatial analysis showed that humpback dolphins aggregated in three core‐use areas with higher sighting density within the survey area. Furthermore, intermediate‐use and broad‐use areas were identified that could be essential for the movements of humpback dolphins among these core‐use areas.
- The spatial usage of humpback dolphins was compared inside and outside the ZLBMHDNR. Results suggest that the ZLBMHDNR is insufficient to encompass a significant portion of dolphin habitat. The ZLBMHDNR (21 km2) is not large enough, and thus it should be expanded for effective place‐based conservation management in this region.
- For developing a protected area network, important dolphin habitats identified in this study should be protected as a single management unit. Additionally, mitigation of anthropogenic pressures is needed to be taken into consideration as conservation initiatives in the study area.
- This study provides support for a more science‐informed protected area network, and highlights the necessity of implementing place‐based conservation and management for the world's second largest humpback dolphin population.
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Rodrigo H. Tardin Israel S. Maciel Mariana A. Espcie Gabriel Melo‐Santos Sheila M. Simo Maria Alice S. Alves 《水产资源保护:海洋与淡水生态系统》2020,30(4):775-786
- Species distribution modelling has been used to identify critical habitats for the delimitation of Marine Protected Areas. Although Marine Protected Areas may often overlap with the distribution of key marine species, illegal human activities often continue within these areas, causing negative impacts on the local biodiversity.
- A generalized linear model with spatial eigenvector mapping was used to investigate, for the first time, the influence of environmental variables and anthropic activities on the number of Guiana dolphin, Sotalia guianensis sightings/grid, and to determine whether a Marine Reserve, in south‐eastern Brazil, is adequate for the protection of the local population. Data were collected between May 2007 and October 2013 onboard a 7.5‐m vessel with an inboard engine.
- The models for the different periods (annual, dry, and rainy seasons) all indicated that depth, the distance to seafood farms and fishing grounds, and mean sea surface temperatures influenced the distribution of the dolphins within the study area. The annual and seasonal models predicted that the dolphins prefer a continuous area between Cedro and Pico Islands, a large area that lies outside the limits of the Marine Reserve.
- Although the habitat of Ilha Grande bay is still much less degraded than that inhabited by other nearby Guiana dolphin populations, the results of the present study indicate that anthropic activities in this area influence habitat use by the dolphins. Less than 30% of the area used by the dolphins is protected by the Tamoios Ecological Station (ESEC Tamoios).
- Sotalia guianensis is classified as ‘Vulnerable’ in Brazil, although the marine reserve (ESEC Tamoios) does not protect the core area used by the local dolphin population. The results of the present study provide specific locations for the creation of a new multiple‐use MPA, as suggested by the Brazilian National Action Plan for the Conservation of Small Cetaceans, or the inclusion of a special management programme for the area between Cedro and Pico islands to better protect the dolphins in the ESEC Tamoios buffer zone. The continuation of surveys to better understand the current and future impacts of human activities, and the development of a closer interaction with both the local community and local stakeholders will help to safeguard Ilha Grande Bay and the local Guiana dolphin population.
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Ross A. Griffin Robyn E. Jones Natasha E.L. Lough Charles P. Lindenbaum Maria C. Alvarez Katie A.J. Clark Jonathan D. Griffiths Peter A.T. Clabburn 《水产资源保护:海洋与淡水生态系统》2020,30(6):1121-1136
- Accurately mapping the extent and status of biogenic reefs formed by polychaete worms of the genus Sabellaria is of conservation importance given their protected status across Europe.
- Traditionally, side‐scan sonar (SSS) combined with ground‐truthing in the form of seabed photography and videography has been widely accepted as the most suitable approach for mapping these reefs in the subtidal zone. In highly turbid environments visibility at the seabed can be near zero, however, rendering optical‐based ground‐truthing redundant. Consequently, the true distribution and status of Sabellaria reefs in some shallow subtidal areas around the UK remains unclear despite their designation as Annex‐I features of several Special Areas of Conservation (SACs) under the Habitats Directive.
- Acoustic camera imagery (ACI) collected using acoustic cameras in two deployment configurations matched well with the backscatter signatures of seabed features in corresponding SSS data. The ACI was of suitable resolution for visualizing Sabellaria colony structures, allowing for their Annex‐I ‘reef’ defining attributes (extent, patchiness, and elevation) to be assessed. Colony formation ‘type’ was also distinguishable in the ACI, although confidence in differentiating between low‐lying Sabellaria formations and surrounding substrates was low, particularly when using a pole‐mounted configuration.
- This study provides a proof of concept for using acoustic cameras as tools for ground‐truthing SSS interpretation and assessing the status of Sabellaria bioconstructions in low‐visibility environments. Further development of this approach and incorporating it into statutory monitoring programmes could improve the management of the reef habitats in subtidal areas of the Severn Estuary and other highly turbid environments.
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Prioritizing localized management actions for seagrass conservation and restoration using a species distribution model 
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下载免费PDF全文 Matthew P. Adams Megan I. Saunders Paul S. Maxwell Daniel Tuazon Chris M. Roelfsema David P. Callaghan Javier Leon Alistair R. Grinham Katherine R. O'Brien 《水产资源保护:海洋与淡水生态系统》2016,26(4):639-659
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Site‐fidelity and movement patterns of bottlenose dolphins (Tursiops truncatus) in central Argentina: essential information for effective conservation 下载免费PDF全文
下载免费PDF全文 Els Vermeulen Alejandro Balbiano Florencia Belenguer Daniel Colombil Mauricio Failla Edgardo Intrieri Stefan Bräger 《水产资源保护:海洋与淡水生态系统》2017,27(1):282-292
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为斑节对虾（Penaeus monodon)淡化养殖设计了3种水质管理模式（各设2个水塘）：（1）全封闭式，将纳水河水注入池后不再换水，仅靠降雨淡化盐度；（2）半封闭式，初始水均取自经贮水塘沉淀、曝晒数日的河口水，水深为池深的80%，待幼虾全长至4cm时，据水质状况添加河水；（3）逐步加淡水递降盐度方式，幼虾长至4cm时，每隔1-2d添加2-5cm河水，水满时排出部分水，日均降盐度百分比为0.2%-1.6%，幼虾长至8-10cm时，池水最终盐度可降至淡水范围（S≥0.55)。结果显示，3种方法养殖均获成功，单产为2340-2557kg/hm^2；方法（1）塘的成活率最高，为66.4%-67.3%，盐度降率为12.3%-16.4%，主要离子总量降率为10.9%-19.0%；方法（2）因只添加少量河水，盐度降率仅为32.2%-48.3%，主要离子总量降率为39%-64%；方法（3）的水质类型始终为海水型（ClⅢ^Na），盐度降率52.8%-93.2%，主要离子总量降率为50%-96%。各淡化塘全周期有效氮总量较低，平均为0.21-0.50mg/L，其中NH3-Nt含量占66%以上，DO均呈过饱和状态（109%-198%），pH与COD较高，分别为8.79-9.25与16.55-24.21mg/L。 相似文献
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长江口沿岸水域银鲳资源监测及渔业经济分析 总被引：10，自引：0，他引：10
长江口沿岸水域银鲳资源监测及渔业经济分析曹正光，赵利华（上海市水产研究所，２００４３３）关键词银鲳，资源调查，渔业经济分析，长江口ＲＥＳＯＵＲＣＥＭＯＮＩＴＯＲＩＮＧＯＦ ＰａｍｐｕｓａｒｇｅｎｔｅｕｓＩｎＴＨＥＯＦＦＳＨＯＲＥＷＡＴＥＲＳＯＦＣＨＡ... 相似文献
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Annual bottom‐trawl surveys (1990–2010) were used to examine associations between environmental conditions, spatial distribution, and size‐specific abundance of Greenland halibut Reinhardtius hippoglossoides in the estuary and Gulf of St. Lawrence (EGSL), and to test the influence of hypoxic conditions on habitat selection. Size classes representing juvenile, immature and adult fish were used for the analyses. The highest concentrations of fish were found in the St. Lawrence estuary at both high and low levels of stock abundance. The areas occupied by 50, 75, and 95% of juvenile fish expanded with higher population abundance. However, contrary to our predictions, densities in marginal habitats did not increase at a higher rate than in optimal habitats. Fish longer than 32 cm were distributed over a broader area than juvenile fish. Their abundance explained a limited proportion of the variability in spatial distribution. The spatial dynamics of Greenland halibut in the EGSL is best described by a proportional density model where the rate of increase in local density is associated with population abundance. Habitats selected by Greenland halibut were characterized by low dissolved oxygen (DO) levels. The strong association between high fish densities and low DO concentrations indicates a high tolerance of Greenland halibut to hypoxia. It also indicates that negative effects, if present, could be compensated by other factors such as food availability and/or refuge from predation. The results of this study also clearly define the St. Lawrence estuary as the major nursery area for the EGSL population. 相似文献
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