Unexpectedly high catch-and-release rates in European marine recreational fisheries: implications for science and management

Abstract

While catch-and-release (C&R) is a well-known practice in several European freshwater recreational fisheries, studies on the magnitude and impact of this practice in European marine recreational fisheries are limited. To provide an overview of the practice and magnitude of C&R among marine recreational anglers in Europe, the existing knowledge of C&R and its potential associated release mortality was collected and summarized. The present study revealed that in several European countries over half of the total recreational catch is released by marine anglers. High release proportions of . 60% were found for Atlantic cod (Gadus morhua), European sea bass (Dicentrarchus labrax), pollack (Pollachius pollachius), and sea trout (Salmo trutta) in at least one of the studied European countries. In the case of the German recreational Baltic Sea cod fishery, release proportions varied considerably between years, presumably tracking a strong year class of undersized fish. Reasons for release varied between countries and species, and included legal restrictions (e.g. minimum landing sizes and daily bag limits) and voluntary C&R. Considering the magnitude of C&R practice among European marine recreational anglers, post-release mortalities of released fish may need to be accounted for in estimated fishing mortalities. However, as the survival rates of European marine species are mostly unknown, there is a need to conduct post-release survival studies and to identify factors affecting post-release survival. Such studies could also assist in developing species-specific, best-practice guidelines to minimize the impacts of C&R on released marine fish in Europe.

Estimating and mitigating the discard mortality of Atlantic cod (Gadus morhua) in the Gulf of Maine recreational rod-and-reel fishery

“…Therefore, to mitigate injury and mortality associated with recreational discards of Atlantic cod in the GOM, it is recommended that anglers favour the use of bait over jigs, reel cod to the surface at a slow-to-moderate pace (as to reduce fight time but not elevate potential barotrauma), minimize handling times, and avoid fishing areas inhabited by small cod. Since anglers are more likely to rely on state and federal natural resource programmes for current regulations and "best practice" techniques rather than scientific literature (Pelletier et al, 2007;Ferter et al, 2013), it is also recommended to promote the accessibility and accuracy of angler education programmes. Finally, while in the midst of the present cod crisis and associated zero bag possession regulations for the recreational fishery (Department of Commerce, 2015), anglers should attempt to avoid areas where cod aggregate during fishing trips that are targeting other groundfish species.…”

“…In addition, the frequency with which fish are discarded by recreational anglers is increasing due to more strict regulatory controls (e.g. possession and size limits) and increased conservation ethics among the angling community (Bartholomew and Bohnsack, 2005;Ferter et al, 2013). However, the efficacy of management techniques such as catch-and-release angling for reducing fishing mortality rates relies on the premise that discarded fish will survive the capture and handling process (Wydoski, 1977;Cooke and Schramm, 2007).…”

Recreational fisheries in the Netherlands: analyses of the 2015 screening survey, the 2014-2015 logbook survey and the 2014-2015 Gillnet survey

“…Unfortunately, only few C&R studies are available. Ferter et al (2013) stressed the need for post release mortality studies to estimate total fishing mortality and to develop best practises guidelines to minimize the impacts of C&R on released marine fish in Europe. In Table 2-6 rough estimates of C&R mortalities are presented for the species studied in this report.…”

“…Two studies for cod are available; (Weltersbach and Strehlow, 2013) estimated C&R mortality for cod in the Baltic Sea by recreational charter boats to be 11%. However, water depths in this study area were relatively shallow (between 8.5 and 14 m) compared to the cod fishing by charter boats in the Dutch part of the North Sea.…”

“…Unfortunately hardly any C&R studies are available for key species such as cod, seabass and eel, and the C&R mortality estimates are therefore very rough estimates. Post release mortality studies to estimate total fishing mortality and to develop best practises guidelines to minimize the impacts of C&R on released marine fish in Europe are highly needed (Ferter et al ,2013).…”