Article
Fisheries
Isabella Maria Friederike Kratzer, Mollie Elizabeth Brooks, Sabri Bilgin, Suleyman Ozdemir, Lotte Kindt-Larsen, Finn Larsen, Daniel Stepputtis
Summary: This study demonstrates the feasibility of using a modified gillnet with small acrylic glass spheres to reduce bycatch of harbor porpoises in a commercial fishery. The focus of pilot experiments was on gear handling and identifying requirements for a full-scale trial, with promising results shown for reducing bycatch of endangered echolocating marine mammals and no negative impact on catch efficiency of vulnerable bottom-dwelling species.
FISHERIES RESEARCH
(2021)
Article
Multidisciplinary Sciences
Soren Post, Flemming Merkel, Zita Bak-Jensen, Christoffer Koch, Rasmus Berg Hedeholm
Summary: Bycatch in gillnets is a global issue, particularly in the North Atlantic lumpfish fisheries where there are no permanent initiatives to reduce it. Researchers in West Greenland experimented with modified gillnets that included a small-meshed net panel at the bottom, resulting in a 71% reduction in common eider bycatch and a 25% reduction in female lumpfish catch rate. It is recommended to further study the net modification's effect and explore the option of postponing the fishing season to reduce bycatch.
ROYAL SOCIETY OPEN SCIENCE
(2023)
Article
Environmental Sciences
Simon D. Goldsworthy, Brad Page, Derek J. Hamer, Andrew D. Lowther, Peter D. Shaughnessy, Mark A. Hindell, Paul Burch, Daniel P. Costa, Shannon L. Fowler, Kristian Peters, Rebecca R. McIntosh, Frederic Bailleul, Alice I. Mackay, Roger Kirkwood, Dirk Holman, Simon Bryars
Summary: The bycatch of the endangered Australian sea lion in gillnet fisheries off South Australia has been a major threat to its populations. A comprehensive assessment combined with management measures, including spatial closures, observer programs, and incentives for alternate fishing methods, resulted in a significant reduction in sea lion bycatch mortality and a transition to longline fishing. The successful implementation of these measures showcases how effective management can mitigate bycatch mortality of marine mammals.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Fisheries
Dennis Brennecke, Ursula Siebert, Lotte Kindt-Larsen, Henrik Skov Midtiby, Henrik Dyrberg Egemose, Sara Torres Ortiz, Katrin Knickmeier, Magnus Wahlberg
Summary: This study demonstrates that harbor porpoises exhibit strong avoidance behavior and reduced surfacing frequency in response to pinger sounds, indicating the effectiveness of pingers in reducing bycatch. However, there is also a diversity in behavioral responses, with some porpoises not reacting to pinger sounds at all. This suggests that pinger use should be carefully considered and alternative mitigation measures may need to be explored.
FISHERIES RESEARCH
(2022)
Article
Environmental Sciences
Dimitar Popov, Galina Meshkova, Karina Vishnyakova, Julia Ivanchikova, Marian Paiu, Costin Timofte, Ayaka Amaha Ozturk, Arda M. Tonay, Ayhan Dede, Marina Panayotova, Ertug Duzgunes, Pavel Gol'din
Summary: Bycatch in fishing gear, particularly bottom gillnets and trammel nets, is causing a significant decline in the Black Sea harbour porpoise population. A study conducted from 2019 to 2021 estimated that the annual bycatch of harbour porpoises in the Black Sea ranges from 11,826 to 16,200 individuals. This poses a serious threat to the long-term survival of the population and immediate measures are needed to reduce the bycatch.
FRONTIERS IN MARINE SCIENCE
(2023)
Article
Biology
Lotte Kindt-Larsen, Gildas Glemarec, Casper W. Berg, Sara Konigson, Anne-Mette Kroner, Mathias Sogaard, David Lusseau
Summary: Incidental captures (bycatch) of harbour porpoise in European Union fisheries remain a significant threat to cetaceans. A long-term monitoring program in Denmark using electronic monitoring has provided detailed data on porpoise bycatch and gillnet fishing effort. The study highlights the importance of considering fishing characteristics in estimating bycatch rates and emphasizes the need for effective monitoring methods and mitigation techniques.
PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES
(2023)
Review
Environmental Sciences
Ida Carlen, Laetitia Nunny, Mark P. Simmonds
Summary: Conservation efforts for harbor porpoises in Europe, particularly in the Baltic Proper and Black Sea, are failing, with populations critically endangered and legal protections proving ineffective. Despite calls for action, issues such as public disinterest and political will hinder progress. Recommendations have been made to address threats, but a complex web of commitments and interactions poses challenges for conservation and management efforts.
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Fisheries
Petr Blabolil, Martin Cech, Vladislav Drastik, Michaela Holubova, Lubos Kocvara, Jan Kubecka, Milan Muska, Marie Prchalova, Milan Riha, Zuzana Sajdlova, Marek Smejkal, Michal Tuser, Mojmir Vasek, Lukas Vejrik, Ivana Vejrikova, Jiri Peterka, Tomas Juza
Summary: This study evaluated the precision of fish community indicators based on reduced gillnet scenarios derived from triplet gillnets using data from 99 surveys in 29 artificial lakes in the Czech Republic. The results showed that setting one gillnet in an appropriate depth strata and lake locality is sufficient for unbiased overall estimates, reducing sampling effort and minimizing unwanted fish mortality.
FISHERIES RESEARCH
(2021)
Article
Environmental Sciences
Charla Jean Basran, Guojon Mar Sigurosson
Summary: This study found significant under-reporting of cetacean bycatch in fisher logbooks, with observers reporting much higher numbers in trawls, nets, and hook and line gears. Despite legal requirements, fishers lack incentives to report and have concerns over negative repercussions to the industry. Introduction of electronic monitoring may provide a more viable option for obtaining reliable bycatch estimates and could potentially replace logbook reporting.
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Multidisciplinary Sciences
Yann Rouxel, Rory Crawford, Ian R. Cleasby, Pete Kibel, Ellie Owen, Veljo Volke, Alexandra K. Schnell, Steffen Oppel
Summary: The study showed that a device called the 'Looming eyes buoy' (LEB) could effectively reduce the number of long-tailed ducks around gillnets, indicating the potential for above-water visual devices to contribute to reducing seabird bycatch. However, some habituation to the LEB was detected during the project duration.
ROYAL SOCIETY OPEN SCIENCE
(2021)
Article
Fisheries
Isabella Maria Friederike Kratzer, Daniel Stepputtis, Juan Santos, Frauke Luetkefedder, Arne Stoltenberg, Lea Hartkens, Matthias Schaber, Lotte Kindt-Larsen, Finn Larsen
Summary: This study investigates the use of small acrylic glass spheres attached to gillnets to increase their acoustic reflectivity and reduce incidental capture of small cetaceans. The results show that gillnets equipped with these spheres have higher acoustic backscattering strength, with the best performance observed when the sphere-sphere distance is 20 cm. The findings suggest that modifying gillnets with reflective spheres can be an effective way to reduce bycatch of small cetaceans.
FISHERIES RESEARCH
(2022)
Article
Multidisciplinary Sciences
Yann Rouxel, Holmfriour Arnardottir, Steffen Oppel
Summary: Bycatch of seabirds in gillnets is a significant conservation issue in the north Atlantic. This study tested the effectiveness of a floating device called 'looming-eyes buoy' (LEB) in reducing seabird bycatch in the Icelandic lumpfish fishery. The study found no direct effect of LEBs on target lumpfish catch and bycatch, but indicated that fishing depth-based restrictions could effectively eliminate seabird bycatch. The study estimated that limiting fishing to waters deeper than 50 meters could save between 5000 and 9300 seabirds annually, without significant impact on fish catch.
ROYAL SOCIETY OPEN SCIENCE
(2023)
Article
Multidisciplinary Sciences
Dennis Brennecke, Magnus Wahlberg, Anita Gilles, Ursula Siebert
Summary: The harbor porpoise in the Baltic Sea is affected mainly by bycatch in static fishing gear, with significant differences in bycatch due to seasonality and region, higher rates in juveniles, and more during a full moon. Understanding these factors can help strengthen conservation efforts for Baltic harbor porpoises.
Article
Environmental Sciences
David Lusseau, Lotte Kindt-Larsen, Floris M. van Beest
Summary: Human activities at sea are becoming more complex, requiring adaptable management interventions to mitigate their cumulative effects on biodiversity conservation. Coastal cetaceans, particularly harbour porpoises, are threatened by bycatch and the indirect effects of repeated exposure to disturbances such as acoustic disturbances. The prevalence of pingers, used to mitigate bycatch, can affect both bycatch rate and the population consequences of noise disturbance. Understanding the physiological effects on reproductive decisions and behavioural responses to noise is crucial for evaluating the cumulative impacts of bycatch and its mitigations.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Environmental Sciences
Dwi Ariyoga Gautama, Hendro Susanto, Mochammad Riyanto, Ronny I. Wahju, Michael Osmond, John H. Wang
Summary: Small-scale fisheries play an important role in the economic and cultural aspects of coastal areas worldwide. However, these fisheries often have high rates of unintentional catching of protected marine species. Recent studies have suggested that net illumination could be an effective method to reduce sea turtle bycatch in these fisheries. A controlled experiment conducted in a coastal gillnet fishery in Indonesia showed that net illumination significantly reduced sea turtle bycatch, particularly for green sea turtles, without affecting the overall catch and target species. Additionally, the study found that the market value of the catch increased when net illumination was used. These results suggest that net illumination could be a viable conservation tool for small-scale gillnet fisheries in Indonesia and Southeast Asia.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Fisheries
A. D. Rijnsdorp, J. G. Hiddink, P. D. van Denderen, N. T. Hintzen, O. R. Eigaard, S. Valanko, F. Bastardie, S. G. Bolam, P. Boulcott, J. Egekvist, C. Garcia, G. van Hoey, P. Jonsson, P. Laffargue, J. R. Nielsen, G. J. Piet, M. Skold, T. van Kooten, Steven Degraer
ICES JOURNAL OF MARINE SCIENCE
(2020)
Article
Ecology
Ciaran McLaverty, Ole R. Eigaard, Grete E. Dinesen, Henrik Gislason, Alexandros Kokkalis, Anders C. Erichsen, Jens Kjerulf Petersen
MARINE ECOLOGY PROGRESS SERIES
(2020)
Review
Environmental Sciences
Francois Bastardie, Elliot J. Brown, Eider Andonegi, Robert Arthur, Esther Beukhof, Jochen Depestele, Ralf Doering, Ole Ritzau Eigaard, Isabel Garcia-Baron, Marcos Llope, Hugo Mendes, GerJan Piet, David Reid
Summary: The study considers the challenges to fishing and marine ecosystems, identifying and describing various ecosystem challenges and management options to address them. While many EU fisheries face similar challenges, there are also region-specific or individual fishery-specific challenges.
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Multidisciplinary Sciences
Ole R. Eigaard, Bent Herrmann, Jordan P. Feekings, Ludvig A. Krag, Claus R. Sparrevohn
Summary: The Excluder is a new bycatch reduction device that has shown to significantly decrease bycatch numbers and increase overall catch efficiency of target species compared to traditional rigid sorting grids. Through experimental testing, it demonstrated improved sorting capabilities, reduced clogging risks, and enhanced sustainability in the Norway Pout fishery.
Article
Ecology
Ciaran McLaverty, Grete E. Dinesen, Henrik Gislason, Mollie E. Brooks, Ole R. Eigaard
Summary: Bottom trawling has widespread impacts on benthic communities, particularly affecting larger fauna with specific traits such as sessile, deep-living, suspension-feeding, tube-dwelling, subsurface deposit-feeding, burrow-dwelling, and long-lived individuals. Size-based effects of trawling should be considered in impact assessments to improve detectability and provide insights into functional impacts of fishing on the seabed.
MARINE ECOLOGY PROGRESS SERIES
(2021)
Article
Biodiversity Conservation
Andrea A. Cabrera, Elena Schall, Martine Berube, Pia Anderwald, Lutz Bachmann, Simon Berrow, Peter B. Best, Phillip J. Clapham, Haydee A. Cunha, Luciano Dalla Rosa, Carolina Dias, Kenneth P. Findlay, Tore Haug, Mads Peter Heide-Jorgensen, A. Rus Hoelzel, Kit M. Kovacs, Scott Landry, Finn Larsen, Xenia M. Lopes, Christian Lydersen, David K. Mattila, Tom Oosting, Richard M. Pace, Chiara Papetti, Angeliki Paspati, Luis A. Pastene, Rui Prieto, Christian Ramp, Jooke Robbins, Richard Sears, Eduardo R. Secchi, Monica A. Silva, Malene Simon, Gisli Vikingsson, Oystein Wiig, Nils Oien, Per J. Palsboll
Summary: Global warming has significant effects on population dynamics and trophic interactions, particularly for baleen whales and their prey. The study reveals that the post-LGM global warming led to expansions in baleen whale populations in both Southern and North Atlantic Ocean, with pronounced increases in abundance and inter-ocean connectivity. It also highlights the persistent and long-lasting impacts of global warming on marine fauna even after global temperatures stabilized.
GLOBAL CHANGE BIOLOGY
(2022)
Article
Fisheries
Katrina Bromhall, Grete E. Dinesen, Ciaran McLaverty, Ole R. Eigaard, Jens Kjerulf Petersen, Camille Saurel
Summary: Dredging for wild mussels in Denmark's marine protected areas has a significant negative impact on density, species richness, and biological traits in the dredge track, but no significant impact on community composition. The recovery of species richness after 4 months suggests potential for ecological restoration. Areas adjacent to the dredge tracks also showed effects of dredging, indicating a need for further investigation into the impacts on benthic macrofauna.
JOURNAL OF SHELLFISH RESEARCH
(2021)
Article
Fisheries
Isabella Maria Friederike Kratzer, Daniel Stepputtis, Juan Santos, Frauke Luetkefedder, Arne Stoltenberg, Lea Hartkens, Matthias Schaber, Lotte Kindt-Larsen, Finn Larsen
Summary: This study investigates the use of small acrylic glass spheres attached to gillnets to increase their acoustic reflectivity and reduce incidental capture of small cetaceans. The results show that gillnets equipped with these spheres have higher acoustic backscattering strength, with the best performance observed when the sphere-sphere distance is 20 cm. The findings suggest that modifying gillnets with reflective spheres can be an effective way to reduce bycatch of small cetaceans.
FISHERIES RESEARCH
(2022)
Article
Environmental Sciences
Francois Bastardie, Sara Hornborg, Friederike Ziegler, Henrik Gislason, Ole Ritzau Eigaard
Summary: Understanding the drivers of greenhouse gas emissions in food production systems is urgent. This study analyzed the fuel use intensity and economic efficiency of Danish capture fisheries and found differences in fuel use intensity among fisheries and fishing techniques.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Environmental Sciences
Francois Bastardie, David A. Feary, Thomas Brunel, Laurence T. Kell, Ralf Doering, Sebastien Metz, Ole R. Eigaard, Oihane C. Basurko, Valerio Bartolino, Jacob Bentley, Benoit Berges, Sieme Bossier, Mollie E. Brooks, Ainhoa Caballero, Leire Citores, Georgi Daskalov, Jochen Depestele, Gorka Gabina, Martin Aranda, Katell G. Hamon, Manuel Hidalgo, Stelios Katsanevakis, Alexander Kempf, Bernhard Kuehn, J. Rasmus Nielsen, Miriam Puets, Marc Taylor, George Triantaphyllidis, Konstantinos Tsagarakis, Agurtzane Urtizberea, Luc van Hoof, Jasper van Vlasselaer
Summary: The study shows that European Union fisheries are resilient to short-term climate-driven stresses, but may be negatively impacted by long-term climate change trends. However, adopting robust and adaptive fisheries management based on sound scientific advice can improve the long-term resilience of fisheries. It is important to regularly update biological reference points and implement energy-efficient fishing technologies to reduce fuel consumption and costs. Overall, flexible and well-informed management is needed to effectively tackle the challenges posed by climate change in EU fisheries.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Fisheries
J. Rasmus Nielsen, Berthe M. J. Vastenhoud, Sieme Bossier, Flemming Mohlenberg, Asbjorn Christensen, Rabea Diekman, Grete E. Dinesen, Ole R. Eigaard, Mayya Gogina, Michael L. Zettler, Alexander Darr, Francois Bastardie
Summary: This study compared the short term impacts of fishing pressure with the variability induced by environmental drivers on quantitative benthic community impact indicators. The results showed that demersal fishing had evident impacts on all indicators, especially in soft muddy and sandy habitats and during the second quarter of the year. Additionally, all environmental drivers, especially current speed, had significant impacts on all indicators, which were of the same or larger magnitude as fishing impacts. Therefore, when using quantitative benthic fishing impact indicators, the short term influence of environmental drivers and seasonal differences in fishing pressure should be considered.
FISHERIES RESEARCH
(2023)
Article
Environmental Sciences
Ciaran McLaverty, Ole R. Eigaard, Jeppe Olsen, Mollie E. Brooks, Jens Kjerulf Petersen, Anders C. Erichsen, Karin van der Reijden, Grete E. Dinesen
Summary: This study analyzed a comprehensive data set of 5885 nearshore benthic samples and found that bottom trawling has significant impacts on abundance, species richness, and the Benthic Quality Index. However, some commonly used indices, such as AMBI and DKI, were not sensitive to trawling impacts, which may result in underestimating or undetected effects of fishing on benthic macrofauna in coastal monitoring programs in Europe.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2023)
Article
Environmental Sciences
K. J. van der Reijden, V. B. Ernstsen, J. Olsen, G. E. Dinesen, J. O. Leth, O. R. Eigaard
Summary: Accurate seabed substrate maps are crucial for marine management, but obtaining them is challenging due to the high costs of at-sea observations and the uncertainty in spatial models. This study shows that incorporating the spatial distributions of bottom trawl fisheries can improve the accuracy of substrate predictions, providing a novel source of previously unused information for seabed substrate interpolation.
MARINE ENVIRONMENTAL RESEARCH
(2023)
Article
Multidisciplinary Sciences
Marcos Suarez-Menendez, Martine Berube, Fabricio Furni, Vania E. Rivera-Leon, Mads-Peter Heide-Jorgensen, Finn Larsen, Richard Sears, Christian Ramp, Britas Klemens Eriksson, Rampal S. Etienne, Jooke Robbins, Per J. Palsboll
Summary: Direct estimation of germline mutation rate in baleen whales using pedigrees shows higher values than phylogeny-based estimates, similar to estimates for primates and toothed whales. Our results reduce previous genetic-based estimates of preexploitation whale abundance and challenge the explanation of low cancer rates in large mammals.
Article
Environmental Studies
Antonello Sala, Jochen Depestele, Aysun Guemues, Pascal Laffargue, J. Rasmus Nielsen, Hans Polet, Chris J. Smith, Mustafa Zengin, Francois Bastardie, Ole R. Eigaard, Katell G. Hamon, Frank Jensen, Alessandro Lucchetti, Sonia Mehault, Emilio Notti, Nadia Papadopoulou, Andrea Petetta, Mattias Skold, Benoit Vincent, Adriaan D. Rijnsdorp
Summary: The impact of bottom gear fishing depends on the sensitivity of the benthic community, fishing intensity, and the depth of penetration of the gears. Disturbance of benthic populations and physical modification of bottom substrates are the outputs of bottom fishing. Innovative solutions, such as alternative gears and catch stimuli, as well as the adoption of technical innovations, can help reduce the adverse impacts of bottom fisheries on demersal ecosystems. The study also explores strategies to reduce fuel use, greenhouse gas emissions, and bycatch as incentives for the fishing industry to reduce seabed impacts.
Article
Fisheries
Miguel Petrere Jr, Davi Butturi-Gomes
Summary: This short communication aims to raise awareness about the misuse of confidence intervals in Ecology and Fisheries statistical models that ignore the lack of independence.
FISHERIES RESEARCH
(2024)
Article
Fisheries
Peter-John F. Hulson, Benjamin C. Williams
Summary: This study evaluates the impact of considering ageing error and growth variability on the determination of input sample size (ISS) in statistical catch-at-age assessment models. The results show that including these sources of uncertainty decreases the ISS determined through bootstrap methods. This indicates that there is more variability in age composition and conditional age-at-length data than previously accounted for. Including these sources of uncertainty improves the estimation of ISS and subsequently improves the quality of stock assessment models.
FISHERIES RESEARCH
(2024)
Article
Fisheries
Jason M. Cope
Summary: Fishery resource assessment is a complex and challenging task, but with the use of different analysis methods and tools, effective management guidance can be provided even with limited data and resources.
FISHERIES RESEARCH
(2024)
Article
Fisheries
Regina L. Cunha, Joana I. Robalo, Sara M. Francisco, Ines Farias, Rita Castilho, Ivone Figueiredo
Summary: Recent advances in genomics have greatly contributed to the assessment of fish stocks by providing precise identification of genetic boundaries. This study used a genotyping-by-sequencing approach to reveal the existence of an additional genetic cluster of blackspot seabream in the northeast Atlantic, which was not previously identified. Factors such as ocean circulation patterns and local upwelling may play a role in the genetic differentiation observed in this study.
FISHERIES RESEARCH
(2024)
Article
Fisheries
Huihua Lee, Mark N. Maunder, Kevin R. Piner
Summary: Estimating growth is important for fish population assessment. Integrated assessment models and the influence of misfitting size composition data have renewed interest in how growth is modeled. The available data types control how the length-at-age relationship is estimated. Estimating length-at-age is complex due to multiple sources of biological variability and difficulties in obtaining representative samples.
FISHERIES RESEARCH
(2024)
Article
Fisheries
A. Ladino, I. Perez-Arjona, V. Espinosa, M. Chillaron, V. Vidal, L. M. Godinho, G. Moreno, G. Boyra
Summary: This study examines the acoustic properties of skipjack tuna and Atlantic mackerel, both bladderless pelagic fish species, and explains the significant differences observed. The research shows that the differences in material properties of their tissues predict a more than 10 dB greater reduced target strength in skipjack compared to mackerel at certain frequencies.
FISHERIES RESEARCH
(2024)
Article
Fisheries
Nelly Pena-Cutimbo, Cristel Cordero-Maldonado, Clara Ortiz-Alvarez, Joanna Alfaro-Shigueto, Jeffrey C. Mangel
Summary: Bycatch is a global problem for marine megafauna. This study assessed the bycatch interactions of the Peruvian artisanal purse-seine fishery in 2019 and found that all taxa groups were affected by bycatch. Dusky dolphins, guanay cormorants, and eagle rays were the most frequently reported bycatch species.
FISHERIES RESEARCH
(2024)
Article
Fisheries
Jen-Ming Liu, Po-Yuk So
Summary: The set-net fishery is an environmentally friendly fishery posing little risk to the marine ecosystem. This study identified ocean temperature, sea surface factors, and climatic factors as the main factors affecting the installation of set-nets.
FISHERIES RESEARCH
(2024)
Article
Fisheries
Josie L. Palmer, Carina Armstrong, Hasan D. Akbora, Damla Beton, Cigdem Caglar, Brendan J. Godley, Kristian Metcalfe, Meryem Ozkan, Robin T. E. Snape, Annette C. Broderick
Summary: Small-scale fisheries are vital for global food security and cultural heritage, but the lack of information hampers effective management and mitigation of ecological impacts. This study provides the first comprehensive overview of the small-scale fishery fleet in Northern Cyprus. The fleet operates mainly over the continental shelf, using static and demersal gear types, and catches a diverse range of species, some of which are threatened. The findings can be used to improve fisheries management and conservation measures.
FISHERIES RESEARCH
(2024)
