Bycatch and discards: from improved knowledge to mitigation programmes

Abstract

Discarding is considered by many as an important problem in world fisheries. In many regions, data collection onboard commercial vessels has intensified, and the understanding of both human and ecological drivers of discards is improving quickly. Discarding patterns vary widely across regions, fisheries, gears, and species. Fishers' responses to regulations and markets explain these complex patterns, on top of resource availability partly driven by environmental fluctuations. This expanded knowledge base provides an appropriate basis for discussing the discard mitigation measures proposed in various settings. In September 2012, a theme session was convened at the ICES Annual Science Conference in Bergen, Norway, to discuss these issues. This themed set of articles includes several of the studies presented at the theme session. Owing to the wide diversity of drivers and reasons for discarding, no single management measure or even framework is expected to address the issue. Rather, discard mitigation measures need to be tailored to each particular fishery, or even species within a fishery, and the effectiveness of solutions is greatest when they are used in combination with other approaches. Bottom-up approaches to bycatch and discard management, which involve incentive-based solutions to bycatch problems, were agreed to be the most promising.

A synthesis to understand responses to capture stressors among fish discarded from commercial fisheries and options for mitigating their severity

“…Given the wide range of reasons for and against discarding, the context‐specific nature of fisheries (Raby et al., ) and the significant species‐specific differences in responses to capture events (Davis, ), there is unlikely to be a single unifying management solution to address this issue. Rather, discard management measures need to be tailored to the specific management objectives for a given fishery considering impacts to both target and non‐target species if they are to be effective (Rochet, Catchpole, & Cadrin, ). More comprehensive consideration across species groups is needed to identify conflicts as well as mutual benefits from mitigation methods (Gilman, ).…”

Collection and validation of self-sampled e-logbook data in a Mediterranean demersal trawl fishery

“…This is the case of monitoring programs carried out in the European Union under EC Regulation No 199/2008, which were shown to provide variable estimates of commercial catches and discards Rochet et al, 2014).…”

Progress in designing and delivering effective fishing industry–science data collection in the UK

“…For example, many elasmobranch stocks are data‐limited and legislative collections are kerbed due to the relatively small proportion of these species in landings (McCully, Scott, Ellis, & Pilling, ; Simpfendorfer et al., ). However, they are considered ecologically important and several species have restrictive fishing opportunities, and so could easily become choke species as the landing obligation is phased in (Rochet, Catchpole, & Cadrin, ). Better data are likely to lead to improved confidence in status assessments, which would make the resulting management measures easier to communicate to stakeholders.…”