Fishery discards and bycatch: solutions for an ecosystem approach to fisheries management?

Abstract

It has been widely acknowledged that fishery discard practices constitute a purposeless waste of valuable living resources, which plays an important role in the depletion of marine populations. Furthermore, discarding may have a number of adverse ecological impacts in marine ecosystems, provoking changes in the overall structure of trophic webs and habitats, which in turn could pose risks for the sustainability of current fisheries. The present review aims to describe the current state-of-the-art in discards research, with particular emphasis on the needs and challenges associated with the implementation of the Ecosystem Approach to Fisheries Management (EAFM) in European waters. We briefly review the international and European policy contexts of discarding, how discard data are collected and incorporated into stock assessments, selectivity in fishing and the main consequences of discarding for ecosystem dynamics. We then review implementation issues related to reducing discards under the EAFM and the associated scientific challenges, and conclude with some comments on lessons learned and future directions.

Harvest Strategies for an Ecosystem Approach to Fisheries Management in Western Mediterranean Demersal Fisheries

“…Sales of fish outside the official market are especially important in species with high commercial value such as dentex, red scorpionfish, and spiny lobster (Carreras et al, 2015), which are precisely the stocks showing the worst exploitation status. Unreported catches may result in underestimation of fishing mortality, leading to biased stock assessments that hamper achieving a sustainable exploitation (Punt et al, 2006;Bellido et al, 2011). This reinforces the need to sensitize fishermen about the importance of providing the best data possible to scientists in order to help improving the stock assessment and management.…”

Discards of the purse seine fishery targeting small pelagic fish in the eastern Mediterranean Sea

“…The latter has gained attention during the last decade since ecosystem based management (EBM) has been established as a priority in fishery science (Garcia et al 2003). Discards may directly or indirectly alter food web interactions and the ecosystem structure and functioning Kaiser 1998, Bellido et al 2011) and constitute an economic and food source waste (Garcia et al 2003, Bellido et al 2011. Moreover, stock assessments and fishery management have to take into account discard mortality, which is often significant enough and is an important source of error (Kelleher 2005, Bellido et al 2011.…”

Spatio-temporal variability of discards in the fishery of the deep-sea red shrimp <em>Aristeus antennatus</em> in the northwestern Mediterranean Sea: implications for management

“…These species are thrown back to the sea, dead or alive, and constitute the fishery discards (Catchpole et al 2005, Kelleher 2005, Bellido et al 2011. Discarded species may have no commercial interest or may be valuable species that are unmarketable for different reasons (undersized or damaged individuals, exceeded quotas, etc.).…”

“…In fact, up to 60% of the total catch is discarded in some of the most important European trawl fisheries (STECF 2006). In the last few years, after the establishment of the Ecosystem Approach to Fisheries Management as an integrated approach which considers the effects of fisheries on the whole ecosystem (FAO fisheries glossary, http://www.fao.org/fi/glossary/default.asp), estimating discards and developing ad hoc management strategies have been regarded as a priority (Catchpole and Gray 2010, Bellido et al 2011, Hilborn 2011. In Europe, discards are currently a hot topic for fisheries management (Catchpole et al 2005, Johnsen and Eliasen 2011, Sardà et al 2013, Condie et al 2014.…”