Upcoming: Expert Workshop on Barrier Passability

On the 14th and 15th of October 2025, the Free Flow Lab will host an expert workshop on freshwater fish barrier passability in Vigo (Galicia, Spain).

Removing knowledge barriers for more effective conservation of migratory fish

Motivation

The EU Nature Restoration Law requires Member States to reconnect 25,000 km of free flowing rivers by 2030, but efficient restoration of river connectivity relies on being able to prioritize barriers for removal or mitigation. For this, the estimation of barrier passabilities for fish is paramount, but these are notoriously difficult to obtain, as they vary widely depending on barrier characteristics, environmental conditions and differences between species and individuals. There is an urgent need to develop rapid barrier passability assessments that can benefit from novel AI-driven approaches and help deliver on Free-Flowing River targets.

Objectives

In this workshop we will build fuzzy cognitive maps using expert assessment to identify the main drivers of barrier passability. We will also assess the degree of consensus among experts on what makes a barrier passable or impassable for different fish species, and use barrier photographic recordsto train a model to estimate passabilities based on machine vision and fuzzy logic.

Participants

The 2-day workshop will take place at the University of Vigo (Redeiras building) and will be attended by 18 experts on migratory fish from the US (Oregon State University), Austria (BOKU), the Netherlands (Deltares), Hungary (BLRI), UK (University of Southampton, University of Kent), Portugal (University of Lisbon) and Spain (University of Vigo, CSIC, University of Valladolid, Xunta de Galicia).