Cod catches taken by the German recreational fishery in the western Baltic Sea, 2005–2010: implications for stock assessment and management

Abstract

Strehlow, H. V., Schultz, N., Zimmermann, C., and Hammer, C. 2012. Cod catches taken by the German recreational fishery in the western Baltic Sea, 2005–2010: implications for stock assessment and management. – ICES Journal of Marine Science, 69: 1769–1780. Next to the commercial fishery, the recreational fishery plays an important role in the removal of biomass from fish stocks. In this study, we present estimates of German recreational cod (Gadus morhua) catches in the western Baltic Sea between 2005 and 2010. Fishing effort was estimated using a stratified mail survey and annual sales of fishing licences. Catch per unit effort was estimated by stratified random sampling of access points and interviews about completed trips. Length distributions of cod catches were acquired by sampling recreational cod catches from charter boats and data from community fishing events. Estimates of the total cod biomass removed by the recreational fishery fluctuated between 2159 t in 2009 and 4127 t in 2005. Annual recreational fishery cod harvests accounted for a significant share of the total landings, with a yearly variation from 34 to 70% of the German commercial cod landings from the western Baltic Sea. The majority of recreational fishery cod catches were taken from private boats and charter vessels. Because of the amount and specifically the variability of the recreational catches, they are important for the assessment and management of the resource and, therefore, need to be surveyed annually.

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

“…Thus, although the presented release proportions were based on the most current catch estimates, the calculated release proportions may only be representative for these particular years. The two German surveys showed that the release proportions for Baltic cod caught in German (Strehlow et al, 2012). This is in line with the finding that German anglers mainly release fish that are not legal to retain.…”

“…In recent years, following the introduction of European legislation requiring estimation of recreational catches of some species, recreational fisheries have gained increasing attention in European fishery research and management. For example, a recent study in Germany showed that the recreational harvest of cod (Gadus morhua) in the western Baltic Sea accounted for 34 -70% of the German commercial cod landings, indicating that total fishing mortalities need to be adjusted, and that the stock was more productive than previously assumed (Strehlow et al, 2012). As a result of this study, the recreational Baltic Sea cod harvest has been included in the stock assessment since 2013.…”

“…¼ 1) in 2006/2007. However, the survey including both coastal states (Strehlow et al, 2012) showed that release proportions varied substantially from 60% in 2009 to 37% and 27% in 2010 and 2011, respectively. The release proportion in 2012 (29%) was similar to the one in 2011.…”

“…This is in line with the finding that German anglers mainly release fish that are not legal to retain. Strehlow et al (2012) argued that the availability of juvenile cod to anglers in coastal areas is higher due to high abundance of juvenile cod, and more anglers than commercial fishers exploiting these waters. Pickett et al (1995) found a similar development for the release proportions of sea bass by recreational anglers in the UK.…”

The co-existence of recreational and artisanal fisheries in the central parts of the Danube and Sava rivers

“…However, there are frequent conflicts between recreational and professional fishermen (Mendonça, 2014;Teramoto and Diegues, 2014), which is valid also for the rivers studied in this paper (Matulić et al, 2010;Smederevac-Lalic et al, 2012). It became increasingly relevant for fish management to understand the impact of recreational fishing on commercially fished stocks and vice versa (Strehlow et al, 2012;Griffiths and Fay, 2015;Marengo et al, 2015). Therefore, in this research we compare the official data on both kinds of fishing on the Sava and Danube rivers in Croatia and Hungary, before the commercial fishery in Hungary was banned in 2016 (Hirado.…”