Modeling short-term fishing dynamics in a small-scale intertidal shellfishery

Abstract

We assessed the relative contribution of a set of predictors on the short-term dynamics of the yellow clam intertidal fishery in Uruguay based on a community-based data collection program for five consecutive fishing seasons. Results of generalized linear mixed models showed that the occurrence of fishable days depends on the absence of red tide events and prevailing wind conditions, but also was related to the timing of each fishing event throughout the fishing season. Furthermore, higher fishing yields were coincident with the prevalence of northerly offshore winds. Catch per unit of effort levels of each fishing event were mostly related to interannual characteristics of each fishing season and, to a lesser extent, with fisher attributes (gender and age) and the timing of each fishing event. The adverse effect of red tides and unfavorable environmental conditions impose a high degree of uncertainty in this social-ecological system, leading to economic inefficiency. A key challenge for successful management of the yellow clam fishery and other similar small-scale fisheries relies in considering not only the resource and the governance subsystems, but also the dynamics of the resource users, together with relevant external drivers affecting them.