Second workshop on appropriate sampling schemes for protected endangered and threatened species bycatch (WKPETSAMP2)

Following the special request from The Directorate-General for Environment (DG ENV), the Second Workshop on appropriate sampling schemes for protected endangered and threatened species bycatch (WKPETSAMP2) was established by ICES. WKPETSAMP2 was tasked to provide input and results to inform ICES advice to DG ENV on ‘appropriate bycatch monitoring systems at Member State level and on regional coordination’. Thereby ICES WKPETSAMP2 was requested to provide recommendations for improvement of monitoring programmes to ensure that collection of data is adequate to assess population level bycatch; in particular, identifying areas, métiers, gears and vessel types where improvements are needed.

The most relevant EU legislation and policies were summarized regarding protected species bycatch conservation (i.e. Birds Directive, Habitats Directive etc.) and fisheries monitoring and data collection programmes (i.e. EU Data Collection Framework).

Ongoing bycatch monitoring programmes carried out by several Member States were described in terms of sampling methods used, type of data collected, and the difficulties encountered in their implementation and when estimating bycatch. The aim was to cover different regions, and different types of fisheries, PETS species considered so that the programmes described would cover a wide range of cases. Programmes from Norway, Denmark, United Kingdom, Spain, France, Sweden and from the Mediterranean and Black Sea were described.

Based on the lessons learnt from existing at sea data collection programmes, it was judged that the fishing effort, sampling designs and the sampling implementation are the main components that require consideration in the development and planning of programmes that are expected to provide data for inclusion in bycatch risk and mortality assessments, and to help direct mitiga-tion studies. These three components were discussed in detail during the workshop.

Ongoing simulation works were also presented during the meeting. On the one hand, the By-catch Evaluation and Assessment Matrix (BEAM), was presented where the main goal was to evaluate how well monitoring programmes can detect large bycatch events. The Marine Mam-mal Bycatch Impacts Exploration Tools (MMBIET) developed in the United States as an interac-tive web-based app for assessing and managing marine mammal bycatch was also explored Managers do not always have access to high-quality data, and still have to make management decisions. The app´s intended user group is people (managers or other stakeholders) who need to know the long-term impacts of bycatch on a marine mammal population but have very limited information on abundance and/or bycatch. Another relevant tool presented was the ObsCov-gTool that predicts observer coverage performance for a given total fishery effort in relation to three metrics: (1) the conditional probability of observing any bycatch given that bycatch oc-curred in the fishery and the probability of any bycatch in the total fishery effort, (2) the upper confidence limit for total bycatch when none is observed, and (3) precision (coefficient of variation) of the bycatch estimate. Main outputs from another workshop, the Workshop on Estimation of Rare Events (WKRARE), were presented providing an overview of the simulation framework that was developed to be able to test the performance of various estimation methods. Finally, a presentation was provided about how to deal with non-representative samples and the insights from using a phenomenological model.

Regarding the simulation model scenarios, some general recommendations on the use of simula-tions to address bycatch monitoring and estimations were discussed, the existing models that could be adapted for use as simulation models were described. The main sources of bias and uncertainty in the bycatch estimation process were identified and a simulation platform to as-sess bias in bycatch rate estimation processes, (SCOTI: Simulations for Characterising Optimal moniToring Implementations) was introduced. Within the workshop, we continue the extension of SCOTI by introducing heterogeneity in bycatch rate (BPUE) between fishing characteristics within the particular fishery on which simulations would like to focus. For example, aiming to estimate BPUE at métier level 4 (gear type) when the métier level 6 (gear type + target species + mesh size) categories within a particular métier level 4 have varying bycatch rates.

Finally, the Terms of Reference for the upcoming WKPETSAMP3 workshop were defined based on the work carried out during WKPETSAMP2 and considering the main objectives of this Special request coming from DG ENV.