Acronym EelTrace
Category
Fisheries
Title Habitat selection of the European eel Programme National Programme
Instrument (FP6)
Contact Type (FP7)
Strand (Interreg)
NA
Theme (FP7)
Activity Area (FP6)
Regional Area (Interreg)
Action (COST)
NA
Specific Programme (FP7)
NA
Funding source National Coordinator Reinhold Hanel Coordinator email reinhold.hanel@ti.bund.de
Coordinator institution
TI-FI - Thunen Institute - Institute of Fishery Ecology (Germany)
Institutions involved
NA
Start year 2005 End year 2009 Funding (€) € 418,700 Website https://www.thuenen.de/en/fi/abgeschlossene-projekte-fi/the-influence-of-migratory-behavior-and-habitat-preferences-on-the-fitness-of-eels/ Summary This project investigated the migratory behaviour and habitat choice of European eels by otolith microchemical analyses and examined their health status in different water types. It aimed at providing information for the identification of feasible measurements for the protection of this endangered species. The minor and trace element analysis of more than 300 eel otoliths from inland and coastal waters revealed that the migratory behaviour of European eels is complex and that the traditional view of a mandatory freshwater phase must be revised. Instead the analysed eels showed complex individual migration patterns including repeated shifts between fresh and saltwater habitats. The results further indicate that eels that enter inland waters as elvers and remain there until the onset of their spawning migration have a reduced spawner quality compared to individuals that stay in brackish or marine habitats throughout their life. The long lasting stay in inland waters resulted in reduced energy reserves and increased infection intensities with the swimbladder nematode Anguillicola crassus. The examination of the eel parasite community was a central part of the health status determination of eels from the investigated waters. In total, 35 parasite species were identified in the analysed eels. Due to their high infection intensities and their potential pathogenicity, the swimbladder nematode Anguillicola crassus and gill parasites of the Genus Pseudodactylogyrus must be considered as potentially harmful. In contrast, extensive virus analyses indicated that the current level of Herpesvirus anguillae and EVEX distribution does not substantially affect the health status of the European eel within the investigated waters.
Goals:
(1) Investigation of migratory behaviour and habitat choice of eels; (2) experimental investigation of temperature and dietary effects on otolith microchemistry - assessment of health status of eels from different water types; (3) investigation of potential influences of migratory behaviour and habitat choice on the reproductive potential of Anguilla anguilla.
Keywords
Fish;
Diets;
Fish health;
Biology;
Fish habitat;
Eel;
Marine Region
76
Not associated to marine areas
0
Marine Region Map
