Crayfish plague pathogen detected in the Danube Delta – a potential threat to freshwater biodiversity in southeastern Europe

Researchers have detected the crayfish plague pathogen, Aphanomyces astaci, in the highly protected Danube Delta, posing a significant threat to native freshwater biodiversity. Using sensitive real-time PCR testing, 13 out of 40 native narrowclawed crayfish (Astacus leptodactylus) tested positive for the pathogen, indicating its widespread presence in the region. The study suggests that A. astaci may have persisted locally or spread via long-range dispersal, potentially jeopardizing European crayfish populations and freshwater ecosystems across southeastern Europe, previously considered plague-free. This discovery highlights the urgent need for conservation measures to mitigate the impact of invasive species and pathogens on vulnerable aquatic environments.

Schrimpf, A., Pârvulescu, L., Copilaș-Ciocianu, D., Petrusek, A., & Schulz, R. (2012). Crayfish plague pathogen detected in the Danube Delta – a potential threat to freshwater biodiversity in southeastern Europe. Aquatic Invasions, 7(4), 503–510. https://doi.org/10.3391/ai.2012.7.4.007