1
|
Li J, Xing Q, Li X, Arif M, Li J. Monitoring Off-Shore Fishing in the Northern Indian Ocean Based on Satellite Automatic Identification System and Remote Sensing Data. SENSORS (BASEL, SWITZERLAND) 2024; 24:781. [PMID: 38339498 PMCID: PMC10857284 DOI: 10.3390/s24030781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Revised: 01/17/2024] [Accepted: 01/23/2024] [Indexed: 02/12/2024]
Abstract
Satellite-derived Sea Surface Temperature (SST) and sea-surface Chlorophyll a concentration (Chl-a), along with Automatic Identification System (AIS) data of fishing vessels, were used in the examination of the correlation between fishing operations and oceanographic factors within the northern Indian Ocean from March 2020 to February 2023. Frequency analysis and the empirical cumulative distribution function (ECDF) were used to calculate the optimum ranges of two oceanographic factors for fishing operations. The results revealed a substantial influence of the northeast and southwest monsoons significantly impacting fishing operations in the northern Indian Ocean, with extensive and active operations during the period from October to March and a notable reduction from April to September. Spatially, fishing vessels were mainly concentrated between 20° N and 6° S, extending from west of 90° E to the eastern coast of Africa. Observable seasonal variations in the distribution of fishing vessels were observed in the central and southeastern Arabian Sea, along with its adjacent high sea of the Indian Ocean. Concerning the marine environment, it was observed that during the northeast monsoon, the suitable SST contributed to high CPUEs in fishing operation areas. Fishing vessels were widely distributed in the areas with both mid-range and low-range Chl-a concentrations, with a small part distributed in high-concentration areas. Moreover, the monthly numbers of fishing vessels showed seasonal fluctuations between March 2020 and February 2023, displaying a periodic pattern with an overall increasing trend. The total number of fishing vessels decreased due to the impact of the COVID-19 pandemic in 2020, but this was followed by a gradual recovery in the subsequent two years. For fishing operations in the northern Indian Ocean, the optimum ranges for SST and Chl-a concentration were 27.96 to 29.47 °C and 0.03 to 1.81 mg/m3, respectively. The preliminary findings of this study revealed the spatial-temporal distribution characteristics of fishing vessels in the northern Indian Ocean and the suitable ranges of SST and Chl-a concentration for fishing operations. These results can serve as theoretical references for the production and resource management of off-shore fishing operations in the northern Indian Ocean.
Collapse
Affiliation(s)
- Jie Li
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China; (J.L.); (X.L.); (J.L.)
- Shandong Key Laboratory of Coastal Environmental Processes, Yantai 264003, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qianguo Xing
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China; (J.L.); (X.L.); (J.L.)
- Shandong Key Laboratory of Coastal Environmental Processes, Yantai 264003, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xuerong Li
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China; (J.L.); (X.L.); (J.L.)
| | - Maham Arif
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China; (J.L.); (X.L.); (J.L.)
- Shandong Key Laboratory of Coastal Environmental Processes, Yantai 264003, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jinghu Li
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China; (J.L.); (X.L.); (J.L.)
- Shandong Key Laboratory of Coastal Environmental Processes, Yantai 264003, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| |
Collapse
|
2
|
He B, Yan F, Su F, Lyne V, Tang J. Prediction of fishing intensity and trends across South China Sea biogeographic zones. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 899:165691. [PMID: 37482352 DOI: 10.1016/j.scitotenv.2023.165691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 07/06/2023] [Accepted: 07/19/2023] [Indexed: 07/25/2023]
Abstract
The volume of industrial fishing in the South China Sea ranks among the top global sustainable fisheries concerns of the Food and Agriculture Organization (FAO). To better understand the scale of management challenges, biogeographic zones of the SCS were characterized, and within each a multivariate GAM (General Additive Model) was fitted to predict and map the complete fishing activities from 2017 to 2020. Model variables, some incomplete or with gaps, included: VIIRS DNB night-time light imagery; Global Fisheries Watch (GFW) data; satellite Ocean Colour; Sea Surface Temperature; and bathymetry data. Four biogeographic zones with differing fishing patterns and trends were identified. We used cross-validation and the GAM model's own tuning method for model prediction accuracy determination, which performed well in four biogeographic zones (R2 respectively: 0.62, 0.68, 0.74 and 0.71). High-intensity fishing grounds are mainly distributed in offshore continental shelf areas. From 2017 to 2019, high-intensity fishing grounds were located near the Beibu Gulf of Vietnam, south Vietnam, part of the Gulf of Thailand and the central Java Sea, where fishing effort greater than 50 h exceeded average annual SCS fishing intensity for several years. By season, intensity and extent of fishing in Spring were largest. In 2020, due to the impact of COVID-19, except for Spring, fishing volume generally decreased. Our experimental results provide new insights and an adaptable biogeographic modelling methodology to map the scale and intensity of regional fishing activities more accurately and completely. This more comprehensive database, that takes account of intrinsic biogeographic fishery context, will help improve and strengthen the regulation of fishing activities around the world.
Collapse
Affiliation(s)
- Bin He
- School of Geography and Ocean Science, Nanjing University, Nanjing 210023, China; State Key Laboratory of Resources and Environmental Information System, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; Collaborative Innovation Center for the South China Sea Studies, Nanjing University, Nanjing 210023, China.
| | - Fengqin Yan
- State Key Laboratory of Resources and Environmental Information System, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; Collaborative Innovation Center for the South China Sea Studies, Nanjing University, Nanjing 210023, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Fenzhen Su
- School of Geography and Ocean Science, Nanjing University, Nanjing 210023, China; State Key Laboratory of Resources and Environmental Information System, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; Collaborative Innovation Center for the South China Sea Studies, Nanjing University, Nanjing 210023, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Vincent Lyne
- State Key Laboratory of Resources and Environmental Information System, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; IMAS-Hobart, University of Tasmania, Hobart, TAS 7004, Australia.
| | - Jiasheng Tang
- State Key Laboratory of Resources and Environmental Information System, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; Faculty of Geomatics, Lanzhou Jiaotong University, Lanzhou, China.
| |
Collapse
|
3
|
Gimpel A, Werner KM, Bockelmann FD, Haslob H, Kloppmann M, Schaber M, Stelzenmüller V. Ecological effects of offshore wind farms on Atlantic cod (Gadus morhua) in the southern North Sea. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 878:162902. [PMID: 36934919 DOI: 10.1016/j.scitotenv.2023.162902] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 03/12/2023] [Accepted: 03/12/2023] [Indexed: 05/13/2023]
Abstract
Evaluating the ecological effects of the rapid expansion of offshore renewables at local, regional and ecosystem-wide scales is essential to understand the overall socio-ecological trade-offs also for other sectors such as fisheries. Hence, little is known about the ecological impact on demersal fish. To shed light on this topic, we studied the effects of an offshore wind farm in the southern North Sea on different life stages of Atlantic cod (Gadus morhua) using a combination of sampling methods at varying spatial and temporal scales. Our investigations of diet composition and trophic niches indicate that cod utilizes wind turbine piles with scour protection as feeding grounds. Furthermore, collected information on cod adults and early life stages during winter spawning season suggest that spawning activity occurred in winter across the wider wind farm area. We conclude that wind turbine foundations with a scour protection can function as artificial reefs that have local positive effects on the resilience of local cod populations. With our study we contribute to urgently needed observational evidence regarding the ecological impact of offshore wind farm installations to inform area-based management and future monitoring activities.
Collapse
Affiliation(s)
- A Gimpel
- Thünen Institute, Federal Research Institute for Rural Areas, Forestry and Fisheries, Institute of Sea Fisheries, Herwigstraße 31, 27572 Bremerhaven, Germany; Federal Maritime and Hydrographic Agency, Department Management of the Sea, Divison Assessment and Monitoring, Section Ecosystem Analyses, Neptunallee 5, 18057 Rostock, Germany.
| | - K M Werner
- Thünen Institute, Federal Research Institute for Rural Areas, Forestry and Fisheries, Institute of Sea Fisheries, Herwigstraße 31, 27572 Bremerhaven, Germany
| | - F-D Bockelmann
- Helmholtz-Zentrum Hereon, Institute for Carbon Cycles, Department of Applied Modelling and Quantitative Methods, Max-Planck-Str. 1, 21481 Geesthacht, Germany
| | - H Haslob
- Thünen Institute, Federal Research Institute for Rural Areas, Forestry and Fisheries, Institute of Sea Fisheries, Herwigstraße 31, 27572 Bremerhaven, Germany
| | - M Kloppmann
- Thünen Institute, Federal Research Institute for Rural Areas, Forestry and Fisheries, Institute of Sea Fisheries, Herwigstraße 31, 27572 Bremerhaven, Germany
| | - M Schaber
- Thünen Institute, Federal Research Institute for Rural Areas, Forestry and Fisheries, Institute of Sea Fisheries, Herwigstraße 31, 27572 Bremerhaven, Germany
| | - V Stelzenmüller
- Thünen Institute, Federal Research Institute for Rural Areas, Forestry and Fisheries, Institute of Sea Fisheries, Herwigstraße 31, 27572 Bremerhaven, Germany
| |
Collapse
|
4
|
Favoretto F, López-Sagástegui C, Sala E, Aburto-Oropeza O. The largest fully protected marine area in North America does not harm industrial fishing. SCIENCE ADVANCES 2023; 9:eadg0709. [PMID: 37256961 DOI: 10.1126/sciadv.adg0709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Accepted: 03/20/2023] [Indexed: 06/02/2023]
Abstract
Marine protected areas (MPAs) that ban fishing restore marine life within their boundaries and can also replenish nearby fisheries. However, some argue that after large MPAs are established, fishing effort is displaced to unprotected areas and economic loss is incurred by the fishing industry. We tested these assumptions by assessing the behavior and productivity of the Mexican industrial fishing fleet before and after the implementation of the largest fully protected MPA in North America (the 147,000-square kilometer Revillagigedo National Park). We found no decrease in catches and no causal link between the variation of the spatial footprint of the industrial fleet and the implementation of the MPA. Our findings add to growing evidence that well-designed MPAs benefit marine ecosystems and, in the long term, can also benefit the fisheries they support.
Collapse
Affiliation(s)
- Fabio Favoretto
- Centro para la Biodiversidad Marina y la Conservación, A.C., Calle del Pirata 420, Col. El Mezquite, La Paz, BCS, México
- Scripps Institution of Oceanography, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Catalina López-Sagástegui
- Gulf of California Marine Program, Institute of Americas, UC San Diego Campus, 10111 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Enric Sala
- National Geographic Society, Washington, DC 20036, USA
| | - Octavio Aburto-Oropeza
- Scripps Institution of Oceanography, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| |
Collapse
|
5
|
Zhang C, Chen Y, Xu B, Xue Y, Ren Y. The dynamics of the fishing fleet in China Seas: A glimpse through AIS monitoring. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 819:153150. [PMID: 35041965 DOI: 10.1016/j.scitotenv.2022.153150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 12/30/2021] [Accepted: 01/11/2022] [Indexed: 06/14/2023]
Abstract
Monitoring fishing activities is crucial for marine conservation but challenging in practice, because the ability in tracking fisheries has been limited on varying spatial and temporal scales. The challenge is for both developed and developing countries, and is outstanding in China which is characterized by the world's largest fishing fleet. The advance of Automatic Identification System (AIS) provides the opportunity to enforce monitoring and to promote the compliance of responsible fisheries. Here, the dynamics of fishing fleets in China Seas were integrally investigated for the first time. We demonstrated heavy fishing efforts widely distributed across China Seas, whereas most vessels were concentrated along the coastal line. The temporal pattern of fishing efforts was dominated by summer moratorium, and intensive fishing occurred immediately before and after the moratorium. We highlight that most fishing activities occurred in a remarkably limited spatial and temporal scope, particularly trawling vessels which spent a few months on fishing every year and covered a small geographical area. Additionally, considerable fishing efforts have transferred from Eastern China Sea to the coastal areas of south China in response to an extension of summer moratorium, which requires the fishing moratorium beginning one month earlier since 2017. We argue that summer moratorium cannot effectively control overall fishing efforts, but rearrange the same level of efforts in space and time. We highlight caveats in the interpretation of AIS data in terms of reception issues, meanwhile the novel information provided by AIS can refine the understanding of fleet dynamics and contribute to adaptive fisheries management over broad spatial and temporal scales.
Collapse
Affiliation(s)
- Chongliang Zhang
- College of Fisheries, Ocean University of China, Qingdao 266003, China; Field Observation and Research Station of Haizhou Bay Fishery Ecosystem, Ministry of Education, Qingdao 266003, China
| | - Yong Chen
- School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, NY 11794, United States of America
| | - Binduo Xu
- College of Fisheries, Ocean University of China, Qingdao 266003, China; Field Observation and Research Station of Haizhou Bay Fishery Ecosystem, Ministry of Education, Qingdao 266003, China
| | - Ying Xue
- College of Fisheries, Ocean University of China, Qingdao 266003, China; Field Observation and Research Station of Haizhou Bay Fishery Ecosystem, Ministry of Education, Qingdao 266003, China
| | - Yiping Ren
- College of Fisheries, Ocean University of China, Qingdao 266003, China; Field Observation and Research Station of Haizhou Bay Fishery Ecosystem, Ministry of Education, Qingdao 266003, China; Laboratory for Marine Fisheries and Food Production Processes, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao 266000, China.
| |
Collapse
|
6
|
Thoya P, Kadagi NI, Wambiji N, Williams SM, Pepperell J, Möllmann C, Schiele KS, Maina J. Environmental controls of billfish species in the Indian Ocean and implications for their management and conservation. DIVERS DISTRIB 2022. [DOI: 10.1111/ddi.13525] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Affiliation(s)
- Pascal Thoya
- School of Natural Sciences Macquarie University Sydney New South Wales Australia
- Kenya Marine and Fisheries Research Institute Mombasa Kenya
- Institute for Marine Ecosystem and Fisheries Science Center for Earth System Research and Sustainability (CEN) University of Hamburg Hamburg Germany
- Leibniz Institute for Baltic Sea Research Warnemuende (IOW) Warnemuende Germany
| | | | - Nina Wambiji
- Kenya Marine and Fisheries Research Institute Mombasa Kenya
| | - Samuel Mackey Williams
- The Department of Agriculture and Fisheries Queensland Brisbane Australia
- School of Biological Sciences The University of Queensland St Lucia Queensland Australia
| | - Julian Pepperell
- Pepperell Research and Consulting Pty Ltd, Noosaville DC Queensland Australia
| | - Christian Möllmann
- Institute for Marine Ecosystem and Fisheries Science Center for Earth System Research and Sustainability (CEN) University of Hamburg Hamburg Germany
| | | | - Joseph Maina
- School of Natural Sciences Macquarie University Sydney New South Wales Australia
| |
Collapse
|
7
|
Not going with the flow: Ecological niche of a migratory seabird, the South American Tern Sterna hirundinacea. Ecol Modell 2022. [DOI: 10.1016/j.ecolmodel.2021.109804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
8
|
Satellite Observation of the Marine Light-Fishing and Its Dynamics in the South China Sea. JOURNAL OF MARINE SCIENCE AND ENGINEERING 2021. [DOI: 10.3390/jmse9121394] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The South China Sea (SCS) is one of the most important fishery resource bases in the world. Marine fisheries, as a crucial component of regional food security and national revenue, raise wide concern about marine ecology, social-economic and political consequences at regional, national and local scales. The large-scale dynamic detection and analysis of fishing activity in the SCS is still unclear because of the accessibility of in-site data, finite automatic identification system (AIS) usage, complex geopolitics and poor additional data coverage. Nighttime light imagery (NTL) derived from low light imaging sensors and the popularity of light fishing in the SCS offers a unique way to unveil fishing activities and its dynamics. In this study, we proposed a set of algorithms for automatic detection of nighttime fishing activity and provided the first large-scale dynamic analysis of nighttime fishing activity in the SCS using monthly Visible Infrared Imaging Radiometer Suite (VIIRS) images between 2012 and 2019. The proposed method effectively minimized the spatio-temporal fluctuations in radiance values of background and their implications to ship detection by integrating high radiance gradient detection and local adaptive thresholding. Further, nighttime fishing activity trajectories were decomposed into trend and seasonal components by using Hilbert-Huang transformation (HHT) to accurately access general trends and the seasonality of nighttime fishing activity in the SCS. The typical subregions analysis, environmental driver analysis, correlation coefficient analysis and hot spot analysis were integrated to characterize the nighttime fishing activity. It appears that the nighttime fishing activity in the SCS exhibited spatio-temporal variability and heterogeneity and was shaped by policy and natural factors such as holidays, annual Chinese fishery moratoria in the Chinese Exclusive Economic Zone (EEZ) and seasonal tropical storm activity.
Collapse
|
9
|
Barbini SA, Sabadin DE, Román JM, Scarabotti PA, Lucifora LO. Age, growth, maturity and extinction risk of an exploited and endangered skate, Atlantoraja castelnaui, from off Uruguay and northern Argentina. JOURNAL OF FISH BIOLOGY 2021; 99:1328-1340. [PMID: 34181283 DOI: 10.1111/jfb.14839] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 05/19/2021] [Accepted: 06/24/2021] [Indexed: 06/13/2023]
Abstract
The spotback skate Atlantoraja castelnaui (Arhynchobatidae) is a large and threatened skate species subjected to fishing pressure, endemic to the Southwest Atlantic that occurs from Rio de Janeiro, Brazil, to San Jorge Gulf, Argentina. The age, growth, age at maturity and the maximum intrinsic rate of population increase rmax of A. castelnaui were studied using 152 specimens collected from off Uruguay and north Argentina (35°-42° S), between June 2013 and February 2020. Vertebrae from 143 individuals were used for ageing (females: n = 83, size range 404-1300 mm total length, TL; males: n = 60, size range 400-1270 mm TL). Maximum ages determined for females and males were 30 and 28 years, respectively. To fit growth models, non-linear and Bayesian estimation approaches were considered. For the first approach, a set of four candidate growth (size-at-age) models were fitted: three-parameter von Bertalanffy, two-parameter von Bertalanffy with fixed L0 , Gompertz and Logistic. In the second approach, von Bertalanffy, Gompertz and Logistic were fitted. For non-linear estimation, model selection indicated that the entire set of candidate growth models were supported by the data. The von Bertalanffy was selected as the best model for Bayesian estimation. There were no differences in growth between sexes. For the sexes combined, the von Bertalanffy growth model by Bayesian method was considered the most adequate to describe the growth of A. castelnaui (growth mean parameters ± S.D.: L∞ = 1210.29 ± 40.68 mm; k = 0.12 ± 0.01 years-1 ; L0 = 179.20 ± 11.62 mm). The age at maturity was estimated at 16.21 and 14.04 years for females and males, respectively. The maximum intrinsic rate of population increase rmax was estimated as 0.252 years-1 . Life-history traits and rmax provided in the present study suggest that this species has a relatively low productivity and may be vulnerable to an intense fishing pressure.
Collapse
Affiliation(s)
- Santiago A Barbini
- Biología de Peces, Instituto de Investigaciones Marinas y Costeras, Universidad Nacional de Mar del Plata, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - David E Sabadin
- Biología de Peces, Instituto de Investigaciones Marinas y Costeras, Universidad Nacional de Mar del Plata, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Jorge M Román
- Biología de Peces, Instituto de Investigaciones Marinas y Costeras, Universidad Nacional de Mar del Plata, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Pablo A Scarabotti
- Instituto Nacional de Limnología, Universidad Nacional del Litoral, CONICET, Santa Fe, Argentina
| | - Luis O Lucifora
- Instituto Nacional de Limnología, Universidad Nacional del Litoral, CONICET, Santa Fe, Argentina
| |
Collapse
|
10
|
Connan M, Perold V, Dilley BJ, Barbraud C, Cherel Y, Ryan PG. The Indian Ocean 'garbage patch': Empirical evidence from floating macro-litter. MARINE POLLUTION BULLETIN 2021; 169:112559. [PMID: 34116371 DOI: 10.1016/j.marpolbul.2021.112559] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 05/24/2021] [Accepted: 05/25/2021] [Indexed: 06/12/2023]
Abstract
Marine litter has become a global issue with 'garbage patches' documented in all ocean gyres. The Pacific and Atlantic garbage patches have been well described, but there are few empirical data for the Indian Ocean. In the austral summer 2019-2020, we conducted an at-sea survey of macro-litter in the rarely investigated south-west Indian Ocean. Over 24 days, 1623 man-made items were observed including plastic fragments, packaging and fishing-related items during 216 h of observations covering 5464 km. More than 99% of the litter items were plastics of which almost 60% were white. Floating litter was patchily distributed with only five items (0.2%) recorded south of 40°S (0.1 items·km-2). Half of the items were encountered over a two-day period south-east of Madagascar (30°S; 59-67°E; 75.2 items·km-2). Our survey detected an accumulation of litter in the southern Indian Ocean and demonstrated that this area warrants more research.
Collapse
Affiliation(s)
- Maëlle Connan
- Marine Apex Predator Research Unit, Institute for Coastal and Marine Research, Department of Zoology, Nelson Mandela University, Port Elizabeth, South Africa.
| | - Vonica Perold
- FitzPatrick Institute of African Ornithology, DSI-NRF Centre of Excellence, University of Cape Town, Rondebosch, South Africa
| | - Ben J Dilley
- FitzPatrick Institute of African Ornithology, DSI-NRF Centre of Excellence, University of Cape Town, Rondebosch, South Africa
| | - Christophe Barbraud
- Centre d'Etudes Biologiques de Chizé, UMR 7372 du CNRS-La Rochelle Université, 79360 Villiers-en-Bois, France
| | - Yves Cherel
- Centre d'Etudes Biologiques de Chizé, UMR 7372 du CNRS-La Rochelle Université, 79360 Villiers-en-Bois, France
| | - Peter G Ryan
- FitzPatrick Institute of African Ornithology, DSI-NRF Centre of Excellence, University of Cape Town, Rondebosch, South Africa
| |
Collapse
|
11
|
Collins C, Nuno A, Benaragama A, Broderick A, Wijesundara I, Wijetunge D, Letessier TB. Ocean‐scale footprint of a highly mobile fishing fleet: Social‐ecological drivers of fleet behaviour and evidence of illegal fishing. PEOPLE AND NATURE 2021. [DOI: 10.1002/pan3.10213] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Affiliation(s)
- Claire Collins
- Centre for Ecology and Conservation College of Life and Environmental Sciences University of Exeter Penryn UK
- Institute of Zoology Zoological Society of London London UK
| | - Ana Nuno
- Centre for Ecology and Conservation College of Life and Environmental Sciences University of Exeter Penryn UK
- Interdisciplinary Centre of Social Sciences (CICS.NOVA) School of Social Sciences and Humanities (NOVA FCSH) NOVA University Lisbon Lisboa Portugal
| | | | - Annette Broderick
- Centre for Ecology and Conservation College of Life and Environmental Sciences University of Exeter Penryn UK
| | | | | | - Tom B. Letessier
- Institute of Zoology Zoological Society of London London UK
- The UWA Oceans Institute University of Western Australia (M092) Crawley WA Australia
| |
Collapse
|
12
|
AIS and VBD Data Fusion for Marine Fishing Intensity Mapping and Analysis in the Northern Part of the South China Sea. ISPRS INTERNATIONAL JOURNAL OF GEO-INFORMATION 2021. [DOI: 10.3390/ijgi10050277] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
For the sustainable development of marine fishery resources, it is essential to comprehensively, accurately, and objectively obtain the spatial characteristics and evolution law of fishing intensity. However, previous studies have focused more on the use of single data sources, such as AIS (Automatic Information System) and VBD (VIIRS boat detection), to obtain fishing intensity information and, as such, have encountered some problems, such as insufficient comprehensive data coverage for ships, non-uniform spatial distribution of data signal acquisition, and insufficient accuracy in obtaining fishing intensity information. The development of big data and remote sensing Earth observation technology has provided abundant data sources and technical support for the acquisition of fishing intensity data for marine fisheries. Based on this situation, this paper proposes a framework that integrates the data of fishing vessels from two sources (AIS, with high space-time granularity, and VBD, with short revisit cycle and high sensitivity), in order to obtain such information based on closely matching and fusing the vector point data of ship positions. With the help of this framework and the strategy of indirectly representing fishing intensity by data point density after fusion, the spatial characteristics and rules of fishing intensity in typical seasons (February, April, September, and November) in the northern South China Sea in 2018 were systematically analyzed and investigated. The results revealed the following: (1) Matching and fusing AIS and VBD data can provide a better perspective to produce robust and accurate marine fishery intensity data. The two types of data have a low proximity match rate (approximately 1.89% and 6.73% of their respective inputs) and the matching success for fishing vessels in the data was 49.42%. (2) Single AIS data can be used for nearshore (50 to 70 km) marine fishery analysis research, while VBD data reflect the objective marine fishing in space, showing obvious complementarity with AIS. (3) The fishing intensity grid data obtained from the integrated data show that high-intensity fishing in the study area was concentrated in the coastal area of Maoming City, Guangdong (0–50 km); the coastal area of Guangxi Beihai (10–70 km); around Hainan Island in Zhangzhou (10–30 km); and the Sanya nearshore area (0–50 km). However, it did not decay with increasing offshore distance, such as at the Trans-Vietnamese boundary in the Beibu Gulf, near the China–Vietnam Common Fisheries Area (50 km) and high-intensity fishing areas. (4) The obtained fishing intensity data (AIS, VBD, and AIS + VBD) were quantitatively analyzed, showing that the CV (Coefficient of Variation) of the average for each month (after fusing the two types of data) was 0.995, indicating that the distribution of the combined data was better than that before fusion (before fusion: AIS = 0.879, VBD = 1.642). Therefore, the integration of AIS and VBD can meet the need for a more effective, comprehensive, and accurate fishing intensity analysis in marine fishery resources.
Collapse
|
13
|
Rodríguez JP, Fernández-Gracia J, Duarte CM, Irigoien X, Eguíluz VM. The global network of ports supporting high seas fishing. SCIENCE ADVANCES 2021; 7:7/9/eabe3470. [PMID: 33637531 PMCID: PMC7909883 DOI: 10.1126/sciadv.abe3470] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Accepted: 01/15/2021] [Indexed: 05/28/2023]
Abstract
Fisheries in waters beyond national jurisdiction ("high seas") are difficult to monitor and manage. Their regulation for sustainability requires critical information on how fishing effort is distributed across fishing and landing areas, including possible border effects at the exclusive economic zone (EEZ) limits. We infer the global network linking harbors supporting fishing vessels to fishing areas in high seas from automatic identification system tracking data in 2014, observing a modular structure, with vessels departing from a given harbor fishing mostly in a single province. The top 16% of these harbors support 84% of fishing effort in high seas, with harbors in low- and middle-income countries ranked among the top supporters. Fishing effort concentrates along narrow strips attached to the boundaries of EEZs with productive fisheries, identifying a free-riding behavior that jeopardizes efforts by nations to sustainably manage their fisheries, perpetuating the tragedy of the commons affecting global fishery resources.
Collapse
Affiliation(s)
- Jorge P Rodríguez
- Instituto de Física Interdisciplinar y Sistemas Complejos IFISC (UIB-CSIC), Palma de Mallorca, Spain.
- ISI Foundation, Turin, Italy
- Institute for Biocomputation and Physics of Complex Systems (BIFI), University of Zaragoza, 50018 Zaragoza, Spain
| | - Juan Fernández-Gracia
- Instituto de Física Interdisciplinar y Sistemas Complejos IFISC (UIB-CSIC), Palma de Mallorca, Spain
| | - Carlos M Duarte
- Red Sea Research Centre (RSRC) and Computational Bioscience Research Centre (CBRC), King Abdullah University of Science and Technology, Thuwal 23955, Saudi Arabia
- Arctic Research Center, Aarhus University, DK-8000 Aarhus, Denmark
| | - Xabier Irigoien
- AZTI Marine Research, Pasaia, Spain
- IKERBASQUE, Basque Foundation for Science, Bilbao, Spain
| | - Víctor M Eguíluz
- Instituto de Física Interdisciplinar y Sistemas Complejos IFISC (UIB-CSIC), Palma de Mallorca, Spain
| |
Collapse
|
14
|
Abstract
Nuclear war, beyond its devastating direct impacts, is expected to cause global climatic perturbations through injections of soot into the upper atmosphere. Reduced temperature and sunlight could drive unprecedented reductions in agricultural production, endangering global food security. However, the effects of nuclear war on marine wild-capture fisheries, which significantly contribute to the global animal protein and micronutrient supply, remain unexplored. We simulate the climatic effects of six war scenarios on fish biomass and catch globally, using a state-of-the-art Earth system model and global process-based fisheries model. We also simulate how either rapidly increased fish demand (driven by food shortages) or decreased ability to fish (due to infrastructure disruptions), would affect global catches, and test the benefits of strong prewar fisheries management. We find a decade-long negative climatic impact that intensifies with soot emissions, with global biomass and catch falling by up to 18 ± 3% and 29 ± 7% after a US-Russia war under business-as-usual fishing-similar in magnitude to the end-of-century declines under unmitigated global warming. When war occurs in an overfished state, increasing demand increases short-term (1 to 2 y) catch by at most ∼30% followed by precipitous declines of up to ∼70%, thus offsetting only a minor fraction of agricultural losses. However, effective prewar management that rebuilds fish biomass could ensure a short-term catch buffer large enough to replace ∼43 ± 35% of today's global animal protein production. This buffering function in the event of a global food emergency adds to the many previously known economic and ecological benefits of effective and precautionary fisheries management.
Collapse
|