Assessment of the status of small-scale fisheries resources in north-west Spain (Galicia) using length- based assessment methods

2nd Iberian Symposium on Modeling and Assessment of Fishery Resources (SIMERPE2) = 2º Simposio Ibérico de Modelado y Evaluación de Recursos Pesqueros, 24-27 October 2023, El puerto de Santa MaríaSmall-scale fisheries (SSFs) are major contributors to global catches and local economies, yet SSFs have historically been under-represented in national and international policies. In the European Union (EU), more than 80% of the fishing fleet is considered small-scale, and Galicia (NW Spain) is one of the most fisheries-dependent regions in Europe, with around 4000 fishing vessels, of which ~90% are registered as artisanal vessels. However, due to various data limitations, there is a lack of formal assessment of the main commercial species that could be used to implement better management practices. To overcome this shortcoming, and considering that length-frequency data from fisheries catches are probably the most common source of demographic information, a number of length-based methods (LBM) are available as potential assessment tools for use in data-limited scenarios. Therefore, in order to provide insight into the stock status of the main fishery resources of the Galician SSF (12 species of Teleostei, two Chondrichthyes, two Crustacea and two Cephalopoda), we applied two of the most commonly used LBMs, namely length-based indicators (LBI) and length-based spawning potential ratio (LBSPR), and one of the few models that relax the equilibrium assumption, such as the lengthbased integrated mixed effects (LIME). The selected LBMs were applied to the individual size data collected by the Galician Regional Government through the on-board monitoring programme of the SSF fleet, managed by its Technical Unit for Small-scale Fisheries (UTPB), for the period 2000 - 2022. To get an idea of the performance of the LBMs, for each stock we compared the results of the data-limited assessment with time series of the abundance index resulting from the standardization of catch-per-unit-of-effort (CPUE) data collected by the UTPB. This study represents a major step forward in the development of a stock assessment and management framework for one of Europe’s most important SSF fleets, based on the best available data and scientific toolsN