Epibiota comparison between two biogenic substrates: the non-native tunicate Styela clava and the native blue mussel Mytilus edulis
Year: 2020
Type: dissertation
Abstract: With the increase in globalisation, the amount of non-native or alien species have also increased \nconsiderably. It is therefore important to know the impact these species have on native \ncommunities. The island of Sylt, located in the north-eastern part of the German Wadden Sea, is a \npopular tourist destination, as well as an important location for oyster and mussel aquaculture. \nThe aim of my study is to better understand the impact of alien species in fouling communities and \ntheir associated epibiota in the region of the Wadden Sea. To fulfil this aim, I studied the epibiota \nassociated with the two biogenic substrates, the native blue mussel Mytilus edulis and the alien \ntunicate Styela clava. I collected the samples from the marina of List on the island of Sylt, facing \nthe Wadden Sea and, hence, being a critical site where non-native species might settle first. My \nresults show similarities between the substrates with regards to species richness, diversity and \nevenness. The communities of the two substrates are similar with regards to the dominating \nspecies (the amphipod Crassicorophium sextonae) and distinguishing by the presence and \nabundance of certain organisms, such as juvenile blue mussels appearing in high abundances on \nM. edulis. Non-native species appeared on both biogenic substrates, without displaying a clear \npreference. Styela clava might not be a habitat builder like M. edulis, but on an individual scale, \nthe introduced tunicate represents a highly complex microhabitat on par with the native blue \nmussel, sharing and providing resources in an anthropogenic habitat. Based on my results and \nexisting literature, I believe that the tunicate does not pose a threat to the native assemblages of \nthe Wadden Sea.
Author: Maria-Milena Filip
Language: English
Subfield: Global and Planetary Change
Field: Environmental Science
Domain: Physical Sciences
SDG: Life below water
Open Access status: green
OpenAlex ID: W3200520344