Catch and Effort Estimation of Marine Recreational Fisheries in Germany – Mail-Diary versus Mail-Recall Surveys

Recreational angler surveys are the only source to collect data in order to estimate the removal of biomass from fish stocks. Survey design and methodology is hereby most crucial to obtain reliable, consistent and comparable catch and effort data of the recreational fishery. In this paper we presents the multi-frame approach that is being used to estimate marine recreational catch and effort in Germany. This approach went through several modifications and improvements since its establishment in 2004. We show the strengths and weaknesses of the applied methods in an attempt to establish a cost-effective recreational fishery survey. To estimate effort, the off-site methods considered include mail-diary and mail-recall surveys. Findings of a comparison between the two effort estimates are presented with emphasis on catch estimates and bias. To estimate the catch per unit effort on-site surveys were conducted on the basis of stratified random sampling of access-points. Length distribution of cod catches were measured during community fishing events and complemented by sampling of recreational cod catches from charter vessels.