Research

Freshwater biodiversity is among the most diverse yet most threatened components of the biosphere. Despite its ecological importance, freshwater species remain underrepresented in global biodiversity databases, and taxonomic, ecological and molecular information are often maintained in separate systems. Building on the Freshwater Animal Diversity Assessment (FADA), which currently provides a global taxonomic reference for more than 125,000 freshwater animal species, FADAmol aims to establish a pilot framework linking taxonomic and molecular biodiversity information for the Catalogue of Life and other international biodiversity infrastructures. The project will expand FADA by integrating habitat information and linking species to the freshwaterecology.info database, thereby connecting taxonomy with ecological knowledge. It will further incorporate parasitic freshwater animals, including host–parasite relationships and links to published DNA sequence repositories, improving the representation of parasite diversity and supporting One Health applications. Finally, FADAmol will address cryptic ("dark") species by systematically documenting published genetic lineages and linking molecular evidence to formally described taxa. By connecting taxonomic, ecological and molecular information within a single interoperable framework, FADAmol will improve the discoverability, integration and reuse of freshwater biodiversity data. The project will strengthen biodiversity monitoring, facilitate DNA-based species identification, and provide an important contribution to international biodiversity infrastructures supporting the Kunming–Montreal Global Biodiversity Framework and the WHO One Health approach.

The KliMoFisch project is a pilot study designed to develop and test an integrated climate-monitoring concept for fish populations in Austrian running waters. The study addresses the growing evidence that climate change is already affecting native fish fauna, particularly cold-adapted species such as salmonids, whose suitable habitat is expected to shrink as water temperatures rise.12 As a pilot river, the Pielach was selected because it represents several fish zones, has a comparatively good ecological status, and is supported by an extensive historical dataset from previous fish surveys. These features make it well suited for testing a targeted monitoring approach and for evaluating how climate-related changes can be detected in river fish communities.1 The main objective of the project is to assess the methodological feasibility of such a monitoring framework, evaluate the quality and sensitivity of the collected data, and derive recommendations for a possible application in additional rivers. An important part of the study is also the analysis of cost efficiency: the methods used will be systematically compared with respect to data quality, sensitivity, and costs in order to optimize the protocol and estimate the resources required for broader implementation.

Fish populations in Austrian rivers have declined sharply in recent decades due to hydromorphological degradation, energy-related development and climate change. Meanwhile, the impact of fish-eating predators on these already stressed communities is a hotly debated topic. The project aims to quantify the additional predation pressure while taking ecological conditions into account. To this end, historical and current fish stock data on abundance, biomass and population structure, collected since the return of predators, are analysed and examined by water body type and degree of stress, in order to separate the effects of predation from those of habitat and climate factors. In parallel, cross-state data on the occurrence and population trends of predators are compiled and used for relative trend analyses. Using distribution and feeding ecology data, we estimate the consumed fish biomass and spatiotemporal predation pressure, linking them to fish stock trends. The analysis is conducted across scales, from the national level down to the level of selected case study rivers. The results will provide a scientific basis for managing fish-eating predators in the context of protecting and sustainably using Austrian river fish stocks.