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Оценка внутривидового состава региональных группировок молоди кеты (Oncorhynchus keta) в бассейне Охотского моря осенью 2019 г.
No full textThe population and genetic structure of chum salmon in the main reproduction regions of the Russian Far East is presented based on the variability of eight microsatellite loci (Ssa20.19, One101, Oke3, Oki1b, Oki23, Ogo2G, Oke11, Ots102). Four main regional groups have been identified for the purposes of genetic identification. The accuracy of the estimates obtained is calculated for each of the four groups. The authors present the results of genetic identification according to the autumn trawl survey in the Sea of Okhotsk in 2019.Представлена популяционно-генетическая структура кеты по основным регионам воспроизводства Дальнего Востока России на основе изменчивости восьми микросателлитных локусов (Ssa20.19, One101, Oke3, Oki1b, Oki23, Ogo2G, Oke11, Ots102). В целях генетической идентификации определены четыре основные региональные группы, для каждой из которых рассчитана точность получаемых оценок. Приведены результаты генетической идентификации по данным осенней траловой съемки в Охотском море в 2019 г.PublishedNon Referee
Programmes de l’UNESCO pour l’Océan.
No full textThe ocean is where all life began – it shelters 157,000 known species and up to a million species that have yet to be discovered. Earth could not breathe without the ocean – this blue lung absorbs a quarter of global carbon dioxide emissions. In addition, 3 billion people, almost half of humanity, depend directly on the ocean for their livelihoods. Today, however, the future of the ocean is in jeopardy. Climate change is taking its toll. Waters are warming and becoming more acidic; ecosystems are suffering. Over the past 200 years, the planet has lost half of its coral reef cover, as well as three quarters of its mangrove forests. According to a UNESCO report, the ocean may soon stop absorbing carbon and emit it instead. This would be a disaster, to say the least. We cannot rise to these challenges if we remain ignorant of the ocean. Today, only 20% of the ocean’s depths have been explored, even though it covers 71% of the world’s surface. Ocean research remains poorly funded, only receiving a tiny fraction – an average of less than 2 per cent – of national research budgets. At a time when humans are setting their sights on Mars, we need to explore the ocean, the world’s least-known continent. We must redouble our efforts to understand these depths, so we can deliver lasting solutions to the threats they face. And, because the world has the ocean in common, the only effective way we can do this is through multilateralism. UNESCO works towards this goal. With its Intergovernmental Oceanographic Commission joined by 150 Member States, and its expertise in the culture and education fields, UNESCO enables coordinated actions by governments, scientists, the private sector, civil society and other UN organizations. Together, we created the tsunami warnings system, we map the deep ocean, identify species, work to ensure that environmental education and ocean literacy are included in school curricula, and protect underwater heritage. UNESCO is also the guardian of unique ocean sites, which are home to critical biodiversity, geological processes and incomparable beauty. We now have 232 marine Biosphere Reserves and 50 marine World Heritage sites of Outstanding Universal Value across the globe. But there is still a lot to do. Today, UNESCO is ramping up this collective mobilization for the ocean, by leading the United Nations Decade of Ocean Science for Sustainable Development, from 2021 to 2030. In this context, several major international summits will take place this year, amplifying our efforts to better understand – and therefore better protect – the ocean. There are ten years left for humanity to understand that the Earth is first and foremost an ocean. Our fate depends on the way we care for it together.PublishedReferee
Workshop to evaluate proposed assessment methods and how to set thresholds for as-sessing adverse effects on seabed habitats (WKBENTH3).
No full textThe Marine Strategy Framework Directive (MSFD) requires EU Member States to achieve and maintain good environmental status (GES) across their marine waters. WKBENTH3 convened as a hybrid meeting to evaluate benthic assessment methods and indicators for their potential to meet the criteria described under the MSFD Descriptor 6 (seabed integrity). They evaluated a suite of indicator methods, proposed by participants. Those included five indicator methods de-scribing the ‘Condition of the Benthic Habitat’, primarily linked to D6C5, and six indicator meth-ods for ‘Physical Disturbance on Benthic Habitats’, primarily linked to D6C3. Variants of some of the indicators as well as some other commonly used diversity indices were also assessed. A common dataset with broad regional representation was used to compare and contrast indi-cator performance with 17 benthic invertebrate datasets drawn from a range of pressure gradi-ents (14 over gradients of commercial bottom trawling intensity, 2 over gradients of eutrophica-tion and 1 over a pollution gradient). A meta-analysis of the mean response to trawling across all locations showed that most indicators had, on average, declined at the high trawl impact rel-ative to the baseline and a significant effect of trawling was detected for the indicators Commu-nity Biomass, Species Richness, Fraction of long-lived species, Median longevity, Fraction of sen-tinel species - SoS, Relative Margalef diversity index DM’, Shannon Index and Inverse Simpson. The complementarity of the different indices was computed using Spearman correlation coeffi-cients between each of the indices for all gradients, ordering indicators with Ward’s hierarchical clustering. One of the key findings was the identification of four groups of indices that showed clear patterns of association. Considering the link of indicators to different benthic community properties, WKBENTH3 proposed that the assessment of D6 should be carried out selecting a number of indicators drawn from different cluster groups to ensure that components of diver-sity, species sensitivity and abundance (density and/or biomass – or other proxy linked to benthic habitat functioning) are addressed. WKBENTH3 further ranked model-based benthic sensitivity and impact outputs across broad habitat types (BHTs) in eight different subdivisions in order to contrast indicator responses. The ranking showed a broad congruence, however, every subdivision had variation in ranking of BHTs among indicator methods. Further work is needed to determine the cause of those discrep-ancies and to look more closely at the values and the response curves generated. WKBENTH3 developed a worked example of how to estimate thresholds for GES based on the approach of ‘detectable change’. The approach was applied to each of the different pressure gra-dients and to muddy sand habitats. It was not able to estimate thresholds for all gradients da-tasets as the confidence intervals around some relationships were very wide. Experts highlighted that the assessment of seabed integrity needs to ensure that cross-regional, regional, national and local scale assessments can “talk” to each other and that they are complementarity in terms of what aspects of the ecosystem the respective indicators are capturing and what pressure they are tracking (linked to manageable human activity). Cross-regional assessments will inform whether assessments are measuring the same or similar things, allowing for such crosschecking.ICESPublishedReferee
Early winter barium excess in the southern Indian Ocean as an annual remineralisation proxy (GEOTRACES GIPr07 cruise).
No full texthe Southern Ocean (SO) is of global importance to the carbon cycle, and processes such as mesopelagic remineralisation that impact the efficiency of the biological carbon pump in this region need to be better constrained. During this study early austral winter barium excess (Baxs) concentrations were measured for the first time, along 30∘ E in the southern Indian Ocean. Winter Baxs concentrations of 59 to 684 pmol L−1 were comparable to those observed throughout other seasons. The expected decline of the mesopelagic Baxs signal to background values during winter was not observed, supporting the hypothesis that this remineralisation proxy likely has a longer timescale than previously reported. A compilation of available SO mesopelagic Baxs data, including data from this study, shows an accumulation rate of ∼0.9 µmol m−2 d−1 from September to July that correlates with temporally integrated remotely sensed primary productivity (PP) throughout the SO from data spanning ∼20 years, advocating for a possible annual timescale of this proxy. The percentage of mesopelagic particulate organic carbon (POC) remineralisation as calculated from estimated POC remineralisation fluxes over integrated remotely sensed PP was ∼2-fold higher south of the polar front (19 ± 15 %, n=39) than north of the polar front (10 ± 10 %, n=29), revealing the higher surface carbon export efficiency further south. By linking integrated remotely sensed PP to mesopelagic Baxs stock, we could obtain better estimates of carbon export and remineralisation signals within the SO on annual and basin scales.Chllenges 4, 9PublishedReferee
Fisheries Statistical Report Year 2021
No full textThis Seychelles Fisheries Statistical Report present annual updates of fisheries statistics for the industrial, semi-industrial, artisanal, sea cucumber and lobster fishery by vessel type, species, and geographical locations for the year 2021. Profiles of each fishery, summary of data collection and processing procedures are also provided. For the purse seine fishery, 46 purse seiners holding licences to fish inside the Seychelles EEZ reported a total catch of 412,922 MT in the in the Western Indian Ocean (WIO), for the year 2021. This represents a 17% increase over the estimated catch of 353,675 MT reported in the year 2020. The Spanish fleet accounted for 38% of the total catch in the WIO for year 2021, whilst the Seychelles and French fleet accounted for 30% and 19% respectively. A total catch of 43,001 MT was reported inside the Seychelles EEZ during the year 2021 representing a 55% decrease from the 95,668 MT reported for the year 2020. This corresponds to a decrease of 49% in fishing effort in 2021 when compared to the previous year. It is worth noting that the catches and effort reported in 2021, was the lowest recorded inside Seychelles EEZ since 2013 and the decrease may be due to the change in fishing ground, with higher availability of tuna outside Seychelles EEZ. In terms of species composition, Skipjack tuna dominated the total purse seine catches, accounting for 61% of the total catch followed by yellowfin and bigeye tuna representing 29%, and 9% of the total catch respectively. Skipjack, yellowfin, and bigeye tuna catches increased by 13%, 8% and 122% respectively in 2021 when compared to the year 2020. It is worth noting that in 2021, SFA encountered technical issues with its purse seine data processing software which did not allow for the species composition corrections. Hence the species composition provided here may change following species composition correction. The Seychelles flagged purse seiners reported a total catch of 122,855 MT in the WIO in 2021, achieved from a fishing effort of 3,027 fishing days thus giving a mean catch rate of 40.60 MT/fishing day. This represents an increase of 9% in catches and a slight decrease of 6% in fishing effort. In 2020 the Seychelles purse seine fleet reported a total catch of 112,231 MT obtained from a fishing effort of 3,221 fishing days with a mean catch rate of 34.84 MT/fishing day. Species composition of the Seychelles purse seine fleet in the year 2021 comprised of 24% yellowfin tuna (29,407MT), 66% of skipjack tuna (81,390MT) and 9% of bigeye tuna (11,230MT). This represents a decrease of 4% in yellowfin tuna catches and an increased of 8% and 91% in skipjack and bigeye tuna respectively. Like previous years, Port Victoria remained the principal port for tuna transhipment and landing by purse seiners in the WIO during the year 2021. A total of 387,992 MT of tuna was unloaded through port Victoria compared to 335,074 MT in 2020. This represents 93% of the total landing and transhipment for that year and a 16% increase from the previous year. For the industrial longline fishery, 188 vessels licensed to fish in the Seychelles EEZ during year 2021 reported an estimated catch of 25,340 MT, obtained from a fishing effort of approximately 66.6 million hooks. This resulted in a mean catch rate of 0.38 MT/1000 hooks, a much lower catch rate than 0.55 MT/1000 hooks estimated for the previous year. The total catch reported by 162 vessels in the year 2020 was 31,496 MT, obtained from a fishing effort of approximately 57.4 million hooks. Only 58% of the total reported catch or 14,575 MT of fish were reported to have been caught inside of the Seychelles EEZ during the year 2021 despite an increase of 49% in fishing effort inside the Seychelles EEZ. In terms of species composition, bigeye tuna catches accounted for 41% of the total catch whilst Yellowfin tuna, swordfish and the `others’ category represented 27%, 7% and 16% of the total catch comparable to the year 2020. During the year 2021, the 64 Seychelles flagged industrial longliners reported an estimated catch of 14,526 MT representing a decrease of 35% in catches despite just a slight decrease of 2% in fishing effort. During the previous year, the 62 Seychelles flagged vessels reported a total catch of 22,469 MT. Species composition of the Seychelles industrial longline fleet in the year 2021 comprised of 21% yellowfin tuna (3064.2MT), 40% of bigeye tuna (5825.8MT) and 24% of “other species” (3549.7MT). This represents a decrease of 61% and 21% in yellowfin and bigeye tuna catches respectively and an increase of 36% in catches of “Other species”. In the semi-industrial fishery, a total of 375 fishing trips targeting tuna and swordfish were conducted by 41 semi-industrial longliners in the year 2021. This represents an increase of 23% in number of trips targeting swordfish and tuna over the 306 fishing trips conducted in 2020 by 35 vessels. The total catches by the Semi industrial vessels increased by 18% to reached 1,759 MT compared to 1,485 Mt the previous year corresponding to an increase of 36% in fishing effort. In terms of species composition, yellowfin tuna accounted for 89% of the total catch followed by swordfish and bigeye tuna accounting for 6% and 3% of the total catch, respectively. During the previous year, the semi-industrial catches was dominated by yellowfin (86%) followed by swordfish (9%) and bigeye tuna (4%). The mean number of boats operating per month in the artisanal fishery, during the first semester of year 2021 has increased to 327 boats active per month when compared to a mean of 303 boats active per month during the first semester of the year 2020 (the covid19 pandemic period). The highest increased was observed in the mean number of schooner active, 56 in 2021 compared to 43 in the year 2020. The artisanal fleet was still dominated by outboard vessels accounting for 62% of the fleet with whalers and schooners accounting for 19% and 17% respectively. During the first semester of the year 2021, the total artisanal catches increased by 28% to reach 2346 MT compared to a total catch of 1833 MT estimated for the same period the previous year. Typical of previous years, the handline fishery dominated artisanal fisheries catches, accounting for 70% of total landings during the first six months of 2021.The most important species groups landed for the first semester of the year 2021 were carangues (24%), bourgeois (14%) and job (11%). During the first six months of the year 2021, the total fishing effort for handline, trap and net fishery increase by 43%, 58% and 41% respectively. The Catch rate for the handline and net fishery decreased during the first semester of the year 2021 when compared to same period the previous year. The catch rate for trap fishery has remained unchanged. For the sea cucumber fishery, the landings in numbers for the 2020/2021 fishing season were 243,169 Flower teatfish, 53,241 White teatfish, and 38,494 Prickly redfish. This represents a decrease of 10% and 22% for Flower teatfish and White teatfish respectively and an increase of 4% for Prickly redfish compare to the 2019/2020 season. Fishing efforts have increased over the years, with 155 trips completed in 2020-2021, two trips less than the 2019/2020 season. The lobster fishery catch fluctuates from season to seasons. The highest catch of 6.1 MT was recorded in the 2020/2021 season, whereas the lowest catch of 0.61 MT was recorded in the 2013/2014 season. A notable peak in catch was recorded in 2019/2020 following a two-year closure. In terms of catch composition for the targeted species, historically P. penicillatus dominated the catch for all seasons with an average of 2.9 MT per season, followed by P. longipes with an average of 0.9 MT per seasons. A total of 242 fishing trips were recorded during the 2020/2021 season compared to only 196 trips in 2019/2020 representing an increase of 23%.PublishedReferee
Report on the Spiny Lobster Fishery: Summary of Fishing Activity for the 2021-2022 season
No full textSpiny lobsters (Palinuridae) are amongst many marine species with great commercial importance for small-scale fisherman. In Seychelles, the spiny lobster has traditionally been managed as a seasonal closure and limited access (license-limited) fishery. The lobster fishing season usually opens for 3 months. This report presents analyses of the fisheries-dependent data collected from the spiny lobster fishery during the 2021/2022 fishing season and makes comparison between previous fishing seasons. To achieve this, data collected from fishers and sampled Catch and Effort logbooks were used. Statistical analyses to compare sizes between the previous seasons for Panulirus longipes (Long-legged spiny lobster) and Panulirus penicillatus (Pronghorn spiny lobster) were performed. Results for 2021/2022 season showed that snorkeling was the predominant fishing method used. A decrease in both the total catch (1.87 MT) and the number of fishing trips (103 trips) was observed compared to the two previous seasons. In terms of fishing sites, Mahé remains the most dominant area for both total catch (1.29 MT) and number of trips (72 trips) amongst the major fishing sites. A decrease in the number of trips (CPUE) was observed. For the 2021/2022 season, female, and male carapace length (CL) size were mostly constant compared to the two previous seasons. Overall, the data analysis for 2021/2022 season indicates that there was a decline in lobster’s relative abundance, most probably attributed to lobster fishing season being open for three consecutive fishing seasons. The CPUE has decreased by 27% compared to the previous season. The 2022 fisheries independent survey will be conducted during the last quarter of the year to establish the changes in the relative abundance of lobsters.PublishedReferee
Upwelling phenomenon in the marine regions of Southern Central of Vietnam: a review
No full textUpwelling is an oceanographic phenomenon that involves the physical process and contributes to changes in chemistry, biology, and natural resources. So, systematically, it is the particular ecosystems of whole marine regions with the upwelling. The strong upwelling waters in South Central Regions of Vietnam have uncertain features of the East Vietnam Sea (Bien Dong) and special characteristics of a coastal upwelling area, recorded in international scientific papers in the twentieth century. Their first signals were discovered in the early 1930s through conceptual ideas. The upwelling phenomenon is officially confirmed by scientific results of marine investigations of the NAGA Expedition (1959–1961). The paper aims to review and discuss the physical from Vietnamese investigation and results since 1990s. The following factors are the most contributing to forming and developing the strong upwelling in Southern Central Waters: (1) Influence scale (Mezo- and micro-scale); (2) Forming causes and developing mechanism of upwelling phenomenon, such as monsoon, morphography, shoreline, and western boundary current system of the East Vietnam Sea; (3) Influence of the water-mass from Mekong River on the upwelling area; (4) Ecological environmental consequences; (5) Impacts of the atmospheric-oceanic interaction processes on the western EVS on upwelling. Additionally, the review has targeted findings of upwelling phenomenon mainly in Vietnamese waters based on remote sensing analysis and reanalysis data series to simulate their forming, mechanizing, fluctuating models and the impacts of upwelling in the EVS on resources and ecosystems. The coupled atmosphere-ocean models resulted the upwelling mechanisms and formation. The long-time series of upwelling phenomenon (Macroscale) were evaluated by remote sensing and reanalyzed data series. It is also providing the supplementing and detailing causes and mechanisms of upwelling formation; impacts and interactions of upwelling on marine physics and hydrodynamics (ocean vortexes, seawater temperature), biochemical (nutrients, plankton organisms), and resources (fish, seafood). Within the framework of strong upwelling waters in the Southern Central Regions (Vietnam), the review has not only mentioned partly clarified scientific results but also indicates the limitations and challenges which were faced and encountered in the forecasters of upwelling phenomena in the future.PublishedReferee
A review of governance and tenure in inland capture fisheries and aquaculture systems of India
No full textThis situation paper is a background document that summarizes the diversity, complexity, and relevance of tenure systems, rights, and the institutional management of inland fisheries in India. The paper is prepared on the occasion of the ICSF Workshop on Improving Inland Fisheries Governance in India, held at Seva Kendra, Kolkata, on 6th-7th September 2019, in which the objective was to discuss the draft National Inland Fisheries and Aquaculture Policy, Govt. of India, 2019, in relation to the human-rights focus of the FAO Voluntary Guidelines on Small-Scale Fisheries.PublishedReferee
Description of seven new species and two new genera of Physocypria sensu latu (Crustacea, Ostracoda) from Brazilian floodplains.
No full textWe describe seven new species of Physocypria sensu latu from three of the main Brazilian floodplains: Gen. 1 spec. A gen. et spec. nov. and Gen. 1 spec. B gen. et spec. nov. from the Upper Paraná River floodplain and the South Matogrossense Pantanal, Gen. 2 spec. C gen. et spec. nov., Gen. 1 spec. D gen. et spec. nov. and Gen. 2 spec. E gen. et spec. nov. from the South Matogrossense Pantanal only and Gen. 1 spec. F gen. et spec. nov. and Gen. 1 spec. G gen. et spec. nov. only from the Amazon River floodplain. All new species here described were found in sexual populations. Generally, the new species have a short and suboval carapace, with the left valve overlapping the right valve on all sides, except for the dorsal side in some species. The morphology of hemipenis and prehensile palps, together with the shape of the valves, were most important to distinguish the species. However, several other morphological characters from limb chaetotaxy are discussed, e.g., the absence in all new species of the short accompanying seta of the five natatory setae on antenna; the presence in all new species of a long seta next to the two a-seta on the first thoracopod and the presence/absence or length of specific setae on second and third thoracopod. We discuss the taxonomic position of the seven new species by evaluating the validity of extant genera, especially of Keysercypria Karanovic, 2011, and foreshadow that our seven new species represent two new genera of Cyclocypridinae.Sete novas espécies de Physocypria sensu latu foram descritas de três das principais planícies brasileiras: Gen. 1 spec. A gen. et spec. nov. e Gen. 1 spec. B gen. et spec. nov. da planície de inundação do alto rio Paraná e do Pantanal Sul Matogrossense, Gen. 2 spec. C gen. et spec. nov., Gen. 1 spec. D gen. et spec. nov. e Gen. 2 spec. E gen. et spec. nov. somente do Pantanal Sul Matogrossense e Gen. 1 spec. F gen. et spec. nov. e Gen. 1 spec. G gen. et spec. nov. somente da planície de inundação do rio Amazonas. Todas as novas espécies aqui descritas foram encontradas em populações sexuadas. Em geral, as novas espécies têm uma carapaça curta e suboval, com a valva esquerda sobrepondo a valva direita em todos os lados, com exceção do lado dorsal em algumas espécies. A morfologia do hemipênis e dos palpos preênseis, juntamente com a forma das valvas, foram as mais importantes para distinguir as espécies. A ausência em todas as novas espécies das cerdas curtas que acompanham as cinco cerdas natatórias nas antenas; a presença em todas as novas espécies de uma cerda longa ao lado das duas a-cerdas no primeiro toracópode e a presença/ausência ou comprimento de cerdas específicas no segundo e terceiro toracópodes são características presentes nos apêndices utilizadas para distinção dos novos gêneros e espécies. Discutiu-se a posição taxonômica das sete novas espécies avaliando a validade dos gêneros existentes, especialmente da Keysercypria Karanovic, 2011, e concluiu-se que nossas sete novas espécies representam dois novos gêneros de Cyclocypridinae.Master
Wave patterns from an optical model on Serranilla Island Cays, Colombian Caribbean
No full textEn este artículo se presenta la metodología utilizada para estimar batimetría sintética utilizando imágenes satelitales Worldview 2 de la isla Cayos de Serranilla, Caribe colombiano. La estimación se realizó para profundidades menores a 5 m. Para ello se efectuó una correlación de las bandas RGB con los datos batimétricos in situ, obtenidos con una ecosonda monohaz con mejor correlación para la banda roja. Lo anterior permitió generar datos batimétricos en las zonas poco profundas, facilitando así, el ingreso de datos para la implementación del modelo espectral de oleaje SWAN en tres dominios, con el fin de propagar el oleaje desde aguas profundas hasta la barrera arrecifal en inmediaciones de la isla Cayos de Serranilla, con lo cual fueron obtenidos los patrones de oleaje para la zona de estudio.This article presents the methodology used to estimate synthetic bathymetry using Worldview 2 satellite images of the Serranilla Island Cays Colombian Caribbean. The estimate was made for depths of less than five meters. For this, the RGB bands were correlated with in situ bathymetric data, obtained using a single beam echo sounder, with the best correlation found for the Red band. This allowed bathymetric data to be calculated for the shallow areas, thus facilitating the input of data for the implementation of the SWAN spectral wave model in three domains, used to propagate the waves from deep waters to the barrier reef in the vicinity of Serranilla Island Cays , with which the wave patterns for the study area were obtained.PublishedNon Referee