A study led by the CEAB-CSIC has identified individuals of the African-origin tunicate Pyura herdmani in the waters of Galicia (. This is a species of ascidian capable of forming large aggregations, displacing native species, and altering marine ecosystems.
Researchers from the Centre d’Estudis Avançats de Blanes (CEAB-CSIC), the Centro de Investigación Mariña da Universidade de Vigo, the Grupo de Estudo do Medio Mariño (GEMM), the Instituto Español de Oceanografía (IEO-CSIC), and the University of Johannesburg (South Africa) have documented the presence of a new exotic species with invasive potential in the waters of Galicia (in the north-west of the Iberian Peninsula). The species in question is Pyura herdmani, a solitary tunicate of large dimensions originally from Africa.
The study, published in the journal Biological Invasions, was possible thanks to the collaboration of the Hydronauta diving club, which observed and collected the first individuals of this species between 2015 and 2019 in the waters of the Ribeira marina, in the Arousa estuary. Subsequently, in 2022, the scientific team conducted a campaign throughout the estuary, as well as in the Vigo estuary, focusing particularly on marina and recreational port infrastructures where these ascidians tend to attach.
Pyura herdmani is a species that can form large aggregations, displacing native species and altering marine ecosystems. Furthermore, similar species have caused economic problems, such as the excessive colonization of mussel farms, which are vital in the Arousa estuary.
Based on the morphological and genetic analyses carried out during the research, it has been concluded that the specimens found in Galicia originated from the northern coasts of Africa. Given the limited dispersal capacity of the early life stages of such species, the introduction of these specimens can only be explained by transport mediated by human activities. Specifically, in this case, it is believed that the most likely introduction pathway could be associated with fishing fleets operating in the Canary-Saharan Bank that regularly dock in Galicia.
“Research aimed at understanding the characteristics of the artificial introduction of non-native species, as well as their early detection, is crucial to determining whether these species will become invasive, potentially causing severe economic and ecological impacts,” says Marc Rius, researcher at the Centre d’Estudis Avançats de Blanes (CEAB-CSIC) and lead author of the scientific article. “This information provides vital insights and guidance for the immediate management of the issue, enabling efforts to be more effectively directed towards eradicating or at least containing the spread of these species,” explain Xavier Turon and Elsa Vázquez, researchers from CEAB-CSIC and CIM respectively, and co-authors of this work.
Bruno Almón, co-author of the article and researcher at the Centro Oceanográfico de Vigo of the IEO, emphasizes the importance of citizen collaboration: “It is a highly valuable source of information in this type of study, especially from groups that live in close contact with the sea, as it allows for the swift detection of changes occurring in the ecosystems they frequent.” The team notes that it was members of a local diving club who first observed and collected specimens of the ascidian.
Ref. article: Rius, M., Turon, X., Morán, P. et al. 2024. A morphogenetic characterisation of a potentially dominant African marine species in Europe. Biol Invasions 26, 2811-2818 https://doi.org/10.1007/s10530-024-03354-x
L'entrada New exotic species with invasive potential detected ha aparegut primer a CEAB.