ICES Journal of Marine Science

Matsubara, Hana; Blandon, Abigayil; Tomita, Mary; Batten, Sonia; Chiba, Sanae; Fujii, Tetsuo; Hasegawa, Daisuke; Kraan, Marloes; Lipton, Doug; Little, L Richard; Buelna, Alondra Sofia Rodriguez; Makino, Mitsutaku

doi: 10.1093/icesjms/fsaf059pmid: N/A

Following the first symposium held in Brest, France, in 2016, the second Marine Socio-Ecological Systems Symposium (MSEAS) was held in Yokohama, Japan, in 2024, after 4 years of postponement due to the COVID-19 pandemic. In 2016, interdisciplinary efforts to inform ocean governance using the Social-Ecological System (SES) approach was highlighted as highly necessary. MSEAS 2024 emphasized the combination of interdisciplinary and transdisciplinary approaches, exploring and developing new insights in co-designing research and co-producing solution-oriented knowledge, while involving diverse teams and stakeholders. The symposium covered a range of topics, including methods and assessment strategies of how to interpret social–ecological systems, stakeholder perceptions and how to communicate the research, involvement of communities, and the co-creation of science. Additionally, the symposium featured inspirational events for Early Career Ocean Professionals (ECOPs) and explored art–science connections. This graphical record aims to convey the essence of the symposium to a broad audience through illustrations. These graphics by a Japanese illustrator are the result of a participatory process during the conference, based on interviews with session conveners and contributions from participants via an online form.

Gooden, Adrienne; Champion, Curtis; Huveneers, Charlie; Kelaher, Brendan; Butcher, Paul A

doi: 10.1093/icesjms/fsaf062pmid: N/A

Ocean warming is redistributing marine biodiversity globally. Assessing shifts in species distributions is particularly interesting for large, highly mobile marine predators, as their movement ecology increases their propensity to respond to changing environments and move to more suitable habitats. We built multi-variable and temperature-only habitat suitability models for white sharks (Carcharodon carcharias) under historic and future climate scenarios throughout south-eastern Australian bioregions. Models used satellite tag data from 41 white sharks over 6 years (2015–2020) and associated environmental variables. Future model projections were applied using downscaled sea surface temperature to quantify changes in suitable habitat based on temperature between 2024 and 2080 under moderate (SSP2-4.5) and high (SSP5-8.5) climate change scenarios. Suitable thermal habitat for white sharks will likely shift poleward during Austral winter and spring, and equatorward in summer and autumn. By 2080, equatorial bioregions may become unsuitable year-round, while some poleward regions will likely increase in suitability by 27–38% in autumn, winter, and spring. Shifts in thermal suitability will likely alter the timing and extent of seasonal temperature-triggered equatorial migrations and may alter trophic dynamics and human–shark interactions. Our findings will help regional management prepare for ecological and safety implications of changing white shark distribution.

Sun, Xin; Filgueira, Ramón; Jiang, Zengjie; Zhao, Xiang; Zhao, Qi; Li, Peilong; Wang, Linjie; Sun, Yao; Tang, Qisheng

doi: 10.1093/icesjms/fsaf075pmid: N/A

Through biodeposition, oysters increase the flux of organic carbon (OC) that deposits and stabilizes on the seafloor and is potentially recorded in the sediment core. However, the linkage between oyster farming and OC burial has not received much attention. This study selected a typical oyster farm with approximately half a century of farming history in Sanggou Bay, China. The OC burial efficiency during the vicissitude of the farm was reconstructed by estimating OC biodeposition flux and OC burial flux. Additionally, microbial necromass was determined to indicate microbial activities. The results showed an increase in OC burial flux when farming became intensive, reaching an average of 91.60 ± 10.98 g m−2 yr−1 with a mean microbial necromass contribution of 30.51 ± 8.56% to the sediment OC. However, the burial efficiency was negatively correlated with OC biodeposition flux with an average of 30.17 ± 12.19%. The outcomes suggest that oyster farming has a strong OC burial capacity. Nevertheless, biodeposition flux from excessive farming triggers stronger microbial degradation of OC, reducing the ratio of OC from biodeposit to burial.

González-Correa, José Miguel; Martínez, Pedro Poveda; Juanes, Francis; Bayle-Sempere, Just T

doi: 10.1093/icesjms/fsaf081pmid: N/A

Understanding the reproductive behavior of key marine species is essential for effective management of marine protected areas (MPAs). This study investigates the reproductive activity of the dusky grouper (Epinephelus marginatus), a vulnerable species in the Mediterranean Sea, through passive acoustic monitoring (PAM). Over a 3-year period, we recorded and analyzed vocalizations associated with courtship and territorial behaviors in a grouper aggregation hotspot within the Tabarca Island MPA. Our results reveal distinct temporal patterns in vocalization rates, peaking during the summer reproductive season, and show that environmental factors such as turbidity, seabed temperature, photoperiod, and wind significantly influence reproductive sound emissions. This study demonstrates that PAM is a valuable tool for monitoring reproductive behavior and offers practical insights for improving MPA management, ensuring the protection of critical habitats and enhancing the reproductive success of E. marginatus.

Andrews, Evan J; Daly, Jack; Nyiawung, Richard A; Parlee, Courtenay E; Bundy, Alida

doi: 10.1093/icesjms/fsaf055pmid: N/A

Ecosystem-based management is key to achieving sustainable ocean use. To realize this potential, marine ecosystem-based management requires greater involvement of the social sciences and humanities, especially to adopt a more holistic approach and incorporate human–nature interactions. An understanding of the state of marine social science and humanities research and its potential to provide advice for management can inform and further its use. To contribute to a future where marine ecosystem-based management fully utilizes marine social science and humanities research, this analysis systematically scoped and reviewed 176 peer-reviewed social science and humanities papers about marine systems in Atlantic Canada published between 2000 and 2021. The analysis used ecological, economic, social/cultural, and governance objectives defined in an ecosystem-based management framework to structure the analysis. The analysis asked three questions: (i) What is the scope of the social science and humanities literature about aquatic systems in Atlantic Canada? (ii) How does that literature relate to objectives in ecosystem-based management? (iii) To what extent is that literature framed for practical integration of advice into decision making? Results indicate a comprehensive body of research, with potential to inform ecosystem-based management but with limited framing for practical integration. This result highlights missed opportunities for the research to be ready for use in ecosystem-based management. The research offers a framework, method, and strategies to understand and improve the scope and practical use of social science and humanities to inform marine ecosystem-based management in Atlantic Canada and globally.

Utne-Palm, Anne Christine; McQueen, Kate; de Jong, Karen; Tenningen, Maria; Dankel, Dorothy Jane; Hareide, Nils-Roar

doi: 10.1093/icesjms/fsaf061pmid: N/A

Norway is planning large-scale offshore wind development, aiming for 30 GW installed capacity by 2040, while emphasizing co-existence with fisheries. However, the impacts on marine ecosystems and fishing operations remain uncertain. This study investigates the information needed to promote coexistence and identify knowledge gaps. The research involved in-depth interviews with fishers in three Norwegian offshore wind areas, a national media survey of stakeholder opinions, and a literature review on offshore wind farm effects on fisheries. Key concerns from the fishing industry were explored, along with their local ecological knowledge. The study highlights critical knowledge gaps regarding offshore wind farm impacts on fish and fisheries in Norway. The paper concludes with recommendations to promote co-existence between offshore wind and fishing industries, aiming to minimize potential negative effects on fisheries while supporting renewable energy goals.

Fowler, Ashley M; Dowling, Natalie A; Bolton, Philip; Folpp, Heath; Harnwell, Jim; Hughes, Julian M; Lowry, Michael B; Lyle, Jeremy M; Lynch, Tim P; McIlgorm, Alistair; Miles, Nathan G; Nichols, Rachel; Ochwada-Doyle, Faith A; Pepperell, Julian; Tracey, Sean; Chick, Rowan C

doi: 10.1093/icesjms/fsaf066

Terenzini, John; McQuatters-Gollop, Abigail; Falkenberg, Laura J

doi: 10.1093/icesjms/fsaf063pmid: N/A

Effective management of ecosystems requires knowledge of biodiversity and how it is changing. There are, however, some species and regions for which such data are missing. Combining historical records with those added using non-traditional monitoring methods such as citizen science can fill this gap. Jellyfish are one group for which such an approach is advantageous as jellyfish are difficult to observe, with records particularly lacking for understudied regions outside of Europe and North America. Using Hong Kong as an example, we combine historical jellyfish observation records obtained using traditional methods (published from 1910 to current day) with recent records facilitated by citizen science under the Hong Kong Jellyfish Project (published since 2022). The published literature documenting jellyfish records captured using traditional methods for monitoring jellyfish in Hong Kong had recorded 80 species, while contemporary citizen science observations added 25 more jellyfish species, for a new total of 105 jellyfish species in Hong Kong waters. Given these species records, and the regional context, we suggest marine biodiversity in Hong Kong is likely still underestimated and further monitoring—including via citizen science approaches—is required. As recognition of biodiversity improves, the corresponding data will be better able to inform management, such as outlined in the Hong Kong Biodiversity Strategy and Action Plan. While focused here on the example of jellyfish in Hong Kong, we advocate for similar approaches to improve understanding of diverse taxa in other regions which would facilitate the development of more broadly effective and holistic management approaches.

Handegard, Nils Olav; Holmin, Arne Johannes; Pala, Ahmet; Utseth, Ingrid; Johnsen, Espen

doi: 10.1093/icesjms/fsaf069pmid: N/A

Scientific acoustic-trawl surveys collect data that are used to track fish and zooplankton populations over time. Most rely on manual annotation during acoustic target classification, but automated methods have been proposed. Here, we report on a framework for testing deep learning-based acoustic classification models and integrating them into the survey estimation process. The approach was applied to North Sea lesser sandeel (Ammodytes marinus) surveys from 2009 to 2024. Three U-Net-based models were tested: a baseline model, a depth-aware model, and a model trained with similarity-based sampling for the foreground class. A threshold based on the training years was applied to the models’ SoftMax outputs. The official sandeel estimation process was used as a starting point, replacing input data with model predictions. The biomass estimates were generally similar between manual annotations and model-based estimates, but variation existed across years. The baseline model misclassified a surface layer as sandeel and was prone to bottom contamination, causing larger deviations from official estimates. Discrepancies between the similarity-based model and the official estimates resulted from an incorrectly applied SoftMax threshold, leading to missing school interiors and indicating threshold sensitivity. Unlike traditional F1 score evaluations commonly used in image-based classification, our comparison assessed predictions in a survey-relevant context. The evaluation indicated that full automation was not yet feasible, but the predictions could be used as starting points for manual scrutiny. Annotating a subset of the data to refine thresholds or employing more advanced active learning approaches could enhance efficiency. These methods could enable faster, more consistent survey annotation.

Vera-Duarte, Javier; Carrasco, Sergio A; Mettifogo, Bianca; Gaymer, Carlos F; Friedlander, Alan M; Wahle, Richard A; Palma, Álvaro; Hinojosa, Iván A

doi: 10.1093/icesjms/fsaf067pmid: N/A

The Juan Fernández Archipelago (JFA) is a unique ecosystem due to its diversity and high endemism. In recent years, there has been an increase in the populations of the endemic sea urchin Centrostephanus sylviae, generating negative impacts on the ecological and socio-economic systems of the Archipelago. Here, we describe the establishment of C. sylviae and the consequences of its overabundance on the subtidal communities, specifically around Robinson Crusoe and Santa Clara islands. Also, we describe the variation in SST (°C) around both islands during the last 40 years. The increase in abundance of C. sylviae and its community-level impacts (i.e. sessile benthic, macroinvertebrates, and fishes) were documented by visual surveys using scuba diving at various sites during January 2014 (12 sites), March 2017 (12 sites), March 2020 (4 sites), and January 2024 (7 sites). Over this period, the increase of C. sylviae abundance (∼400%) was associated with a significant decrease in sessile biotic benthic cover and an increase in the percentage of barren grounds (40%–84%). Additionally, there was a significant decrease in the abundance of the sea star Patiriella calcarata (100%) and the sea cucumber Mertensiothuria platei (70%). In terms of fish, a decrease in the abundance of the endemic wrasse Malapterus reticulatus (95%), and an increase of the chilean sweeper Scorpis chilensis (40%) were observed. Both species evidenced a decrease in biomass (90% and 84%, respectively). In general, the abundance of C. sylviae could be attributed to the synergistic effects of both top-down and bottom-up processes, including the low presence of predators (Astrotole platei and Jasus frontalis), by the increase in nutrient concentrations, and by the influence of climate change. These results could serve as a baseline for exploring ongoing community changes in subtidal environments.