Introduction to the Proceedings of the Sixth ‘Advances in the Population Dynamics of Stream Salmonids’ Symposium

In May of 2023, about 100 scientists met for the sixth time over ~25 years for the ‘Advances in the Population Dynamics of Stream Salmonids’ Symposium. This symposium, created by the father of brown trout ecology, Dr. Javier Lobón-Cerviá and colleagues, grew out of intriguing conversations regarding the regulation of the population dynamics of salmonids, as long ago as the 1980s. The first symposium was in the quaint coastal town of Luarca, Spain, in 1998 and started out small with less than ~50 scientists in attendance. The second symposium, also more modest in numbers (~85 scientists), was held in 2006 in millenary Leon in the NW of Spain, a town proud of its history and its Cathedral of nearly 2000 square metres of stained glass and in-credible (free!) tapas. The third was in 2010 back in the stunning fishing town of Luarca, where our numbers grew substantially to more than 115, we moved into a fancy new conference hall, and we feasted on fresh seafood. The fourth was in 2015 and held in Girona (101 scientists), in the NE of Spain, where we all felt ethereal while giving our talks in a stunning cathedral-like hall and where we experienced the strong Catalonian culture and cuisine. This was followed by a meeting in Granada, Spain, in 2019, where we strolled the halls and gardens of the magnificent Alhambra after riveting days of science talks. Finally, in May of 2023, we met in lovely and lively Majorca, one of Spain's Balearic Islands in the Mediterranean, and convened at the University of Balearic Islands. We ate delicious foods, as Majorca has many cultural influences, and toured a magnificent cave, where we were serenaded by live classical music. We met with old friends and new friends and shared new experiences, and our numbers of participants grew yet again. Topics covered included the roles of tributaries, influences on growth rates, recruitment, dispersal and migration, genetics, spawning, habitat, innovative conservation, restoration and management, habitat, and even beer and salmon, to name just a few. At each iteration, we have received new fresh faces and perspectives, but our alumni base has held strong, offering continuity in the advancement of the study of the population dynamics of stream salmonids. Selected proceedings from the May 2023 Majorca symposium follow. The articles cover a wide range of topics, from eco-evolutionary dynamics to how to measure biologically relevant temperature in fish, for example. In this way, these proceedings show the importance of understanding and studying stream living salmonids at a wide range of scales. P.B. and L.A.V. both equally conceived of and wrote this short introduction. The authors declare no conflicts of interest.