October 15, 2026 – The invasive swim bladder parasite Anguillicola crassus was found in approximately 43% of European eels (Anguilla anguilla) examined in freshwater and brackish habitats along the Croatian coast. This is the main finding of the paper “Habitat and site-level patterns of Anguillicola crassus infection in European eels from the eastern Adriatic coast (Croatia)”, published in Regional Studies in Marine Science. Two of its authors are from Oikon: Matija Kresonja and Prof. Milorad Mrakovčić.
A study of 674 eels
The data come from the project Monitoring of Eel in Inland Waters under the National Plan for Data Collection in Fisheries of the Republic of Croatia. Between September 2023 and June 2024, 674 eels were collected from freshwater and brackish habitats and examined. The same project recently produced a paper on eel population parameters in Fishes.
What the results show
The authors found no statistically significant difference between freshwater and brackish habitats, either in the share of infected eels or in the average number of parasites per eel examined. The results suggest that the brackish habitats studied should not automatically be considered a refuge from this parasite. This matters for planning the monitoring and protection of the European eel.
The paper is the result of a collaboration between Oikon, the University of Dubrovnik, the Institute of Oceanography and Fisheries in Split and the Hellenic Centre for Marine Research. We thank all co-authors.
Regional Studies in Marine Science is indexed in Web of Science (SCIE) and Scopus, where it ranks Q1 in Animal Science and Zoology and in Ecology, Evolution, Behavior and Systematics.
Congratulations to Matija Kresonja and Prof. Milorad Mrakovčić on another published paper!
- Read the paper: https://www.sciencedirect.com/science/article/abs/pii/S2352485526005244
- Our article on the eel population paper in Fishes: https://oikon.hr/european-eel-croatian-waters-fishes-paper/