Mortality Of Fish Escaping Trawl Gears

Progress has been made in reducing bycatch and discards through improving the selectivity of fishing gear. This publication examines the key factors affecting the stress, injury and mortality of fish arising from fishing processes, particularly when fish escape from trawl equipment. It seeks to identify improved methodological approaches and practices, and to consider the design of fishing gears and operations that reduce or eliminate such deaths, and to assess the problems associated with estimating the impact of unaccounted fish mortality.

BEHAVIOR OF MARINE FISHES BEHAVIOR OF MARINE FISHES: Capture Processes and Conservation Challenges Understanding fish behavior in relation to capture processes in marine fisheries is of fundamental importance to reducing bycatch and discards, and to enhancing marine fisheries conservation efforts. A thorough understanding of this allows commercial fishers to more effectively capture target species while reducing the catch of unwanted species. Behavior of Marine Fishes: Capture Processes and Conservation Challenges provides the reader with principles, patterns, and characteristics on fish behavior and fish capture processes using several types of important commercial fishing gears. The book also highlights conservation challenges facing the marine capture fisheries in efforts to maintain sustainable use of marine resources and to reduce negative impacts to the marine ecosystem. This volume, with contributions from leading applied fish behaviorists and fishing gear technologists from around the world, will be a valuable reference for researchers, fishing gear technologists, fisheries managers, students, and conservationists. SPECIAL FEATURES: Synthesis of current research and valuable knowledge that will help reduce bycatch and discards in commercial fisheries Review of basic fish behavioral principles and patterns and their relation to capture methods and conservation efforts Contributions from leading international applied fish behaviorists and fishing gear technologists

This third update of FAO’s global discard estimate adopted the ‘fishery-by-fishery’ approach employed in the second discards assessment published in 2005. The update included publicly available discard data in the last 20 years to establish a baseline of a time series of global marine fisheries discards. This is essential for monitoring the status and trends of discard management, which is the first step of the ecosystem approach to fisheries management cycle. In addition, the study developed a new fisheries data table incorporating landings data from the FAO Global Capture Production dataset (FishStat J) from 2010 to 2014, which allocated the landings to over 2 000 fisheries worldwide. The current study estimated that the annual discards from global marine capture fisheries between 2010 and 2014 was 9.1 million tonnes (95% CI: 6.7 – 16.1 million tonnes). About 46 percent (4.2 million tonnes) of total annual discards were from bottom trawls that included otter trawls, shrimp trawls, pair bottom trawls, twin otter trawls and beam trawls. The study included a synthesis of estimates of bycatch and discards of endangered, threatened and protected (ETP) species. Substantial advances have been made in quantifying fisheries interactions with such species so as to make informed decisions on their protection. However, many challenges remain, especially for small-scale fisheries. The development of standardized data collection techniques, risk-based sampling and sharing of data across agencies and regions will help to identify management priorities and allow implementation and enforcement of mitigation measures. A review of previous research showed that discard practices were often related to a wide range of factors, so it is difficult to assess the effectiveness of fishery management actions on the amount and practice of discards. Many regulations are inconsistently enforced, and their implementation is often less strict than intended. Piecemeal approaches in many bycatch and discards management measures can result in unintended cross-taxa conflicts, where regulations designed to reduce bycatch and/or discards of one species or species group may increase bycatch and/or discards of another. Examination of approaches to accounting for and mitigating against pre-catch, post-capture and ghost fishing mortalities demonstrates that an understanding of the relative importance of factors affecting indirect fishing mortality is necessary for estimating total fishing-induced mortality and for designing and implementing mitigation measures.

This book investigates how fish experience their lives, their amazing senses and abilities, and how human actions impact their quality of life. The authors examine the concept of fish welfare and the scientific knowledge behind the inclusion of fish within the moral circle, and how this knowledge can change the way we treat fish in the future. In many countries fish are already protected by animal welfare legislation in the same way as mammals, but in practice there is still a major gap between how we ethically view these groups and how we actually treat them. The poor treatment of fish represents a massive animal welfare problem in aquaculture and fisheries, both in terms of the number of animals affected and the severity of the welfare issues. Thanks to its interdisciplinary scope, this thought-provoking book appeals to professionals, academics and students in the fields of animal welfare, cognition and physiology, as well as fisheries and aquaculture management.

With by-catch in fisheries becoming an ever more high-profile problem, this brilliant work could not be more timely. It contains contributions from the world’s leading experts in by-catch reduction, who guide the reader through most aspects of the field. They examine the methodologies used to develop by-catch reduction techniques and provide new avenues for broadening such work. Case studies are provided that encompass most of the world’s fishing techniques and regions.