An Unsupervised Machine Learning Algorithm for the Identification and Tracking of Lagrangian Mesoscale Eddies

International audienceMesoscale eddies are the dominant mechanism of ocean heat transports from the tropics to the poles that help to maintain the extra-tropical climate. In addition to their role in moving heat poleward, mesoscale eddies affect a vertical transfer of heat in the ocean, largely moving heat upwards to partially compensate for the downward heat transport by time mean fields. Automation of the identification and tracking of mesoscale eddies are critical to global climate models that include ocean mesoscale eddies, and to understand the role of eddies in climate. This work proposes a fully automated method that identifies and tracks from a single Lagrangian advection, all mesoscale eddies from birth to death, without prior knowledge of their lifespans. The eddies' detection and tracking use an unsupervised machine learning algorithm, which consists of a hybrid method based on geometrical properties of the evolving velocity along Lagrangian trajectories and a grid density-based clustering algorithm. The high eddies' monitoring capacity of the proposed method is demonstrated by automatically identifying and tracking these structures from two different datasets: satellitederived surface geostrophic velocity fields and a two-dimensional fluid simulation. The proposed approach gives complete dynamical features and evolution of the detected mesoscale eddies by identifying their genesis event, monitoring their coherent core, and describing their splitting and vanishing image

Sustainable seafood using octopus as a model

The global catch of octopus and squid shows annual variability and demand is likely to increase for both locally-supplied and imported products. However, the vulnerability of seafood resources is now well known, the reliability of fisheries catch data is still unclear, management of cephalopod stocks is mostly rudimentary, and there is uncertainty and concern about their sustainability among fisheries managers, the fishing industry, retailers, researchers and consumers. Here, a new project is presented which aims to address and resolve ways to enhance the effectiveness of seafood sustainability in general, with the aid of a freely accessible identification and traceability tool linked to sophisticated databases, and using artificial intelligence, machine learning and blockchain technology, to provide an easy and reliable way to trace seafood using octopus as a model. The project is a contribution to UN Sustainable Development Goals 2, 9, 14, and 17

Overview of ImageCLEFcoral 2021: Coral reef image annotation of a 3D environment

This paper presents an overview of the ImageCLEFcoral 2021 task that was organised as part of the Conference and Labs of the Evaluation Forum - CLEF Labs 2021. The task addresses the problem of automatically segmenting and labelling a collection of underwater images that can be used in combination to create 3D models for the monitoring of coral reefs. The training dataset contained 882 images from 6 subsets from 4 locations. 1 subset was complete (containing all the images to build the 3D model) and 5 subsets containing a partial collection. The test data (491 images) contained the images required to complete 4 of the partial image sets from each of the 4 locations (the final partial subset is not used for testing, only training). 8 teams registered to the ImageCLEFcoral task, of which 3 teams submitted 8 runs. Participants' entries showed that although automatic annotation of benthic substrates was possible, developing a generic algorithm to work across multiple geographical locations will be difficult due to the variation of characteristics within and between classification types

Spatial distribution of Cephalopods of the European Shelf and their associated oceanographic parameters based on occurrence in standardized demersal fishing trawls

Changing oceans impact the whole marine ecosystem in different ways. For example, rising ocean temperatures can affect the presence / absence of species, especially when local environmental conditions exceed individual species’ physiological tolerances. Accordingly, climate change has caused shifts in distribution and expansions for various cephalopods worldwide. Cephalopods play an important role in the ecosystem, especially in food webs. Consequently, spatial distribution shifts might help explain observed ecosystem changes. Therefore, maps for cephalopod distributions need to be reviewed and updated. Meanwhile, information on the associated environmental conditions will permit future occurrence of cephalopods to be modelled, which is interesting from a fishery and ecological perspective. Some information about physiological tolerances of cephalopods are known from laboratory studies and aquaculture experience, as well as from field observations. Laboratory data are often based on narrow ranges, depending on the experimental design, and can therefore provide only a limited understanding of physiological tolerances. On the other hand, field observations are also limited due to the spatial and temporal limitations of surveys, but these might provide a more realistic picture of natural tolerances. Here, we use the ICES Datras dataset to, first, describe the current distribution of cephalopods associated with the European shelf and, second, advance the knowledge regarding environmental ranges of the various species included in the analysis by combining occurrence data with in-situ oceanographic data. An additional literature review will provide information about the different environmental requirements of various life stages. The results allow us to increase the knowledge of physiological preferences of various cephalopod species within the North-East Atlantic Ocean. Finally, we will discuss and present potential future trends in cephalopod occurrence within the NE Atlantic. In order to further strengthen our knowledge of physiological tolerances of various cephalopod species more data on life history and life stages is needed to develop a more advanced mechanistic model.info:eu-repo/semantics/publishedVersio

Cephalopod Fisheries in European waters: stock assessment, forecasting and management

4th International Congress on Applied Ichthyology, Oceanography and Aquatic Environment. Hydromedit, Virtual, 4-6 November 2021N

Management for sustainable cephalopod fisheries in Europe: review and recommendations

Although cephalopod fisheries are of world-wide importance, in Europe catching cephalopods is managed only in small-scale fisheries, at national level, and few stocks are formally assessed. Because cephalopods are not quota species under the EU’s Common Fisheries Policy, there is currently no requirement for assessment or management at European level. Given increasing interest in targeting cephalopods in Europe, there is a risk that they will be fished unsustainably. Although there have been recent review papers on progress in stock assessment and fishery forecasting for commercially fished cephalopods there has been no recent review of cephalopod fishery management. We aim to fill this gap, with a particular focus on European cephalopod fisheries.We review potential barriers to sustainable fishing and reasons why management of cephalopod fisheries differs from that for finfish fisheries, e.g. due to the high inherent volatility and the possibly cyclic nature of year-to-year variation in cephalopod abundance, reflecting their short lifespan, rapid growth and high sensitivity to environmental conditions. We review fishery management approaches in important cephalopod fisheries worldwide (e.g. in the USA, Japan, Falklands, South Africa, Australia and Russia) and current management of small-scale cephalopod fisheries in Europe. We identify knowledge gaps and limitations to current monitoring programmes and stock assessments and discuss the options available for cephalopod fishery management in Europe, considering the suitability or otherwise of catch and effort limits, use of closed areas and seasons, restrictions on sizes caught and types of fishing gear, and the ole of market-based sustainability pathways.info:eu-repo/semantics/publishedVersio

World squid fisheries

Peer reviewedPublisher PD

Towards a global Fishing Vessel Ocean Observing Network (FVON): state of the art and future directions

Ocean observations are the foundation of our understanding of ocean processes. Improving these observations has critical implications for our ability to sustainably derive food from the ocean, predict extreme weather events that take a toll on human life, and produce the goods and services that are needed to meet the needs of a vast and growing population. While there have been great leaps forward in sustained operational monitoring of our oceans there are still key data gaps which result in sub-optimal ocean management and policy decisions. The global fishing industry represents a vast opportunity to create a paradigm shift in how ocean data are collected: the spatio-temporal extent of ocean data gaps overlaps significantly with fishers’ activities; fishing vessels are suitable platforms of opportunity to host communications and sensor equipment; and many fishing vessels effectively conduct a depth-profile through the water column in the course of normal fishing activities, representing a powerful subsurface data collection opportunity. Fishing vessel-collected ocean data can complement existing ocean observing networks by enabling the cost-effective collection of vast amounts of subsurface ocean information in data-sparse regions. There is an emerging global network of fishing vessels participating in collaborative efforts to collect oceanographic data accelerated by innovations in enabling technologies. While there are clear opportunities that arise from partnering with fishing vessels, there are also challenges ranging from geographic and cultural differences in fleets, fishing methods and practices, data processing and management for heterogeneous data, as well as long term engagement of the fishers. To advance fishing vessel-based ocean observation on a global scale, the Fishing Vessel Ocean Observing Network (FVON) aims to maximize data value, establish best practices around data collection and management, and facilitate observation uptake. FVON’s ultimate goals are to foster collaborative fishing vessel-based observations, democratize ocean observation, improve ocean predictions and forecasts, promote sustainable fishing, and power a data-driven blue economy

Ecological-Fishery Forecasting of Squid Stock Dynamics under Climate Variability and Change: Review, Challenges, and Recommendations

24 pages, 3 figures, 5 tablesGlobally, cephalopods support large industrial-scale fisheries and small-scale to partly large-scale local artisanal fisheries. They are of increasing economic importance as evidenced by the rapid rise in their global landings from 1950 to 2014. Cephalopods are sensitive to environmental variability and climate change and many if not all species show wide fluctuations in abundance. This is most evident in ommastrephid nerito-oceanic squid since their life cycle is associated with boundary currents that are changing with climate change. The inter-annual variability in catch presents challenges for fishers and managers due to the ‘boom-or-bust’ nature of the fishery. A key barrier to rational management of squid fisheries is the low level of development of fishery forecasting. Despite substantial progress made in relating squid population dynamics to environmental variability and change, several challenges remain to develop forecast products to support squid fisheries management. Ideally, squid fisheries management needs a forecasting system that includes all time-scales of forecasting, and especially short - and medium-terms forecasts. The present overview first provides current knowledge of the effects of climate change and variability on squid population dynamics, challenges and opportunities to advance ecological-fishery forecast products, and finally a roadmap is proposed for future development of forecasts products to support squid sustainable fisheries management. As for the adoption of specific forecasting methods to the squid fishery management process, what is important is the relationship between needs, feasibility, and the ultimate success of a forecast will be determined by whether it is used by end-usersPeer reviewe