Meeting Abstract

S9-9  Monday, Jan. 6 13:30 - 14:00  The role of understanding the eel’s morphology in stopping its decline DE MEYER, J.*; VERHELST, P.; ADRIAENS, D.; University of Ghent; University of Ghent; University of Ghent jendmeye.demeyer@ugent.be

The European eel (Anguilla anguilla) is a critically endangered species, whose recruitment stocks have declined to nearly 1% compared to the late 70’s. An amalgam of factors are responsible for this, amongst them climate change, migration barriers and habitat loss, pollution, non-native parasites and overfishing. While most studies related to eel conservation focus on these aspects, little attention is given to the eel’s morphology in function of management measures. Worryingly, however, less than 50% of the currently installed management plans reach their goals, strongly indicating that more information is needed about the eel’s morphology, ecology and behavior. In a series of studies, we evaluated how the eel’s morphology is related to several ecological and behavioral factors, which provides new insights to install proper management plans. First, we showed that the eel’s head shape is related to diet, with broader-headed eels being on a higher trophic level than narrow-headed eels. This difference in trophic position subsequently results in pollutant uptake variability: The higher an eel’s position in the food chain, the more pollutants it will accumulate. This link between morphology, ecology and pollution highlights that pollution can affect eels differently. In another study, we evaluated whether broad- and narrow-headed eels differ in migration behavior. Finally, we evaluated burrowing behavior of the European eel and substrate preference. This latter study showed that eels may also suffer from hypoxia and sediment pollution and provides novel insights in how anthropogenic actions such as dredging and extraction of sand and gravel can impact the eel’s behavior. The link between an eel’s morphology, behavior and ecology therefore plays a pivotal role in maintaining the European eel population.