Determinació de l’edat del barb de muntanya (Barbus meridionalis) a diverses poblacions de la conca del riu Ter

Abstract

The Mediterranean barb is a species of the family of cypresses that has been affected by current adverse environmental conditions and by invasive species pressures until it has been classified as a vulnerable species (VU). Its population trend has made it sensitive to changes in the flow patterns, water extraction and habitat alterations. The objective of this work is to give a new focus to the populations that live in five effluents of the Ter basin. The technique used was electric fishing and a subsequent reading of the ages through the scales of each fish caught in the different sections, as well as carrying out a series of statistical analyzes (ALK model) and, the Robson- Chapman and the condition of Fulton in order to estimate the age structure, mortality and condition of the species. The length-weight ratio of the catches has also been estimated in order to provide a database for future biomass studies of this species. In the results obtained it has been observed that it is a really species that is vulnerable to external affections and that its growth in these streams may have been negatively affected. The general situation in which they are found is optimal, but with a clear difference between sections that could have their origin in artificial hydrological changes. Unfavorable biological conditions and competition between introduced species may also have caused their endemism in these rivers to be more regressive. The results should be reaffirmed with the monitoring of the study and the increase in catches in each section to be able to establish the current state of the species and above all, in order to give a more optimal overview of the conditions under which this species lives and grows in the stretches sampled in the Ter basin