Article
Environmental Sciences
Matt K. Broadhurst, Ian A. Knuckey, Russell B. Millar
Summary: Turning conventional diamond-shaped meshes 90 degrees ('T90') in trawl extensions or codends is a simple modification that has improved size selection in European fisheries. However, in the Great Australian Bight, using the T90 mesh in the anterior codend did not significantly affect catches or sizes of discarded or retained species, except for a slightly improved quality of deepwater flathead attributed to the release of abrasive debris from the codend.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Ecology
Alissa M. Ganley, Paul S. Krueger, Ian K. Bartol
Summary: This study examined the maneuverability of two squid species, Doryteuthis pealeii and Illex illecebrosus, using kinematic tracking approaches. The results showed that Illex illecebrosus completed faster but broader turns, while Doryteuthis pealeii relied more on fin flap frequencies and amplitudes for turning. Both species were able to complete tighter turns when oriented arms-first versus tail-first, and Illex illecebrosus curled its arms more in the arms-first mode, likely increasing angular velocity.
JOURNAL OF EXPERIMENTAL MARINE BIOLOGY AND ECOLOGY
(2023)
Article
Environmental Sciences
Matt K. Broadhurst, Ian A. Knuckey, Russell B. Millar
Summary: Investigated the use of larger and more T90 meshes in an Australian fish-trawl codend to improve size selection and reduce discards of deepwater flathead. Larger-meshed codends caught fewer immature flathead but lost some larger fish. The discard percentage in this fishery is likely to remain high (>75%), and efforts to improve selection should consider other modifications besides codend changes.
FRONTIERS IN MARINE SCIENCE
(2023)
Article
Environmental Sciences
Bingzhong Yang, Bent Herrmann
Summary: This study compares the size selectivity and exploitation pattern of diamond-mesh codends with various mesh sizes for cocktail shrimp in the South China Sea. The findings suggest that increasing the mesh size does not significantly improve the size selectivity and exploitation pattern.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Fisheries
Matt K. Broadhurst, Russell B. Millar
Summary: This experiment evaluated the effects of a narrower-than-recommended hooped cover on the conventional trawl codend, as well as the impact of inserting a large panel of smaller square-shaped mesh on the size selection of eastern school whiting. The results suggest that modifying the mesh size in the codend can marginally improve size selection for the targeted fish species.
FISHERIES RESEARCH
(2022)
Article
Fisheries
Chryssi Mytilineou, Bent Herrmann, Danai Mantopoulou-Palouka, Antonello Sala, Persefoni Megalofonou
Summary: This study provides important information for the sustainable development and management of Mediterranean fisheries by investigating the selection patterns of commercial bycatch species in the trawl fishery. It highlights the suitability of different codends for different species, while considering factors such as juvenile protection, discard mitigation, and fisher behavior.
ICES JOURNAL OF MARINE SCIENCE
(2023)
Article
Multidisciplinary Sciences
Vang Y. Nguyen, Shannon M. Bayse, Zhaohai Cheng, Paul D. Winger, Harold DeLouche, Gebremeskel Eshetu Kebede, George Legge
Summary: To reduce the retention of undersized redfish in the trawl fishery, a shaking codend was developed in Canada. The shaking codend uses a mechanical stimulating device to create a shaking motion, stimulating fish movement and increasing the escape of small redfish. The movement and fishing characteristics of the shaking codend were tested and showed promising results in reducing the capture of small redfish.
Article
Fisheries
Zita Bak-Jensen, Bent Herrmann, Juan Santos, Valentina Melli, Daniel Stepputtis, Jordan P. Feekings
Summary: Trawl codends are commonly made of diamond-mesh netting, but the variability in mesh geometry compromises the rationality of size selection. Turning the codend netting 45 degrees to achieve better size selection has shown limited evidence. Our study aimed at quantifying the variability in size selection in square-mesh codends and found that standard square-mesh codends had significantly larger variability compared to fixed diamond-mesh codends.
FISHERIES RESEARCH
(2023)
Article
Fisheries
Matt K. Broadhurst, Russell B. Millar
Summary: The utility of a generic device called a "fisheye" and its simple modification for reducing bycatch in penaeid trawls were assessed in two experiments. Results showed that trawls with the modified fisheye significantly reduced bycatch and undesired fish species. Further experiments demonstrated that a modified design of the fisheye improved fishing performance. These findings support the regional and potential international use of the modified fisheye in fisheries.
FISHERIES RESEARCH
(2023)
Article
Multidisciplinary Sciences
Elsa Cuende, Manu Sistiaga, Bent Herrmann, Luis Arregi
Summary: This study examines the size selectivity and catch patterns of different gear combinations in the Basque bottom trawl fishery. The results demonstrate the significant impact of design changes in square mesh panels and codends on the size selectivity and catch patterns of hake and blue whiting. The study suggests prioritizing research on codend size selectivity and the addition of selection devices once good selective properties are achieved.
Article
Engineering, Marine
Lei Yan, Bingzhong Yang, Peng Zhang, Jie Li, Teng Wang
Summary: This study conducted experiments to assess the selectivity of diamond mesh codends in capturing largehead hairtail in the Beibu Gulf. Different mesh sizes were used, and models were fitted to the catch data to determine the best fit curve. It was found that the present minimum mesh size did not match the landing size and suggestions for the optimal configuration and mesh size were made.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2023)
Article
Fisheries
Elsa Cuende, Manu Sistiaga, Bent Herrmann, Mikel Basterretxea, Luis Arregi
Summary: The study estimates the escape probability of different fish species through a shortened lastridge ropes (LR) codend and quantifies the contribution of mesh opening angles (OAs) to their size selectivity. The results show that high OAs increase escape opportunities for all species, but the shortened LR only significantly improves size selectivity for certain species. The study highlights the importance of considering fish morphology and behavior in optimizing size selectivity when designing shortened LR codends.
MEDITERRANEAN MARINE SCIENCE
(2022)
Article
Fisheries
Zita Bak-Jensen, Bent Herrmann, Juan Santos, Nadine Jacques, Valentina Melli, Jordan P. Feekings
Summary: This study found that the commonly used diamond-mesh codends in demersal trawls tend to have varying mesh geometry during fishing, resulting in an unclear size selection process. By comparing experimental tests, it was discovered that rigid codends with constant mesh geometry have better stability in size selection for Atlantic cod. These findings can guide the design of more suitable codends in future research.
CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES
(2022)
Article
Fisheries
Matt K. Broadhurst, Russell B. Millar
Summary: Efforts in New South Wales, Australia are being made towards developing more efficient and environmentally friendly fishing methods to manage the increasing number of species being harvested with quotas. This study investigates the selectivity of a boat seine with a traditional vs modified codend when targeting two whiting species. The boat seine proved to be highly efficient in harvesting large quantities of whiting, with low discard rates, but there were issues with entanglement and the need for further improvements in the codend design.
FISHERIES RESEARCH
(2023)
Article
Fisheries
Thomas C. Barnes, Matt K. Broadhurst, Daniel D. Johnson
Summary: Over the past decade, efforts have been made to improve the selectivity of baited traps for the giant mud crab in south-eastern Australia. These efforts focused on testing rectangular escape gaps and promoting their use among local fishers. However, there is a lack of data on escape-gap designs and their performance in unassessed regions of the fishery. A fishery-wide observer-based assessment was conducted to address this deficit. The assessment revealed that traps with rectangular escape gaps significantly reduced the number of undersized crabs, while traps with circular escape gaps did not have the same effect.
FISHERIES RESEARCH
(2023)
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)