Líffræðifélag Íslands - biologia.is
Líffræðiráðstefnan 2021

Erindi/veggspjald / Talk/poster E97

Towards the management of an invasive tunicate

Höfundar / Authors: Joana Micael (1), Pedro Rodrigues (2), Sindri Gíslason (1), Alfonso Ramos-Esplá (3)

Starfsvettvangur / Affiliations: 1. Náttúrustofa Suðvesturlands, 2. Rannsóknastöðin Rif/Rif Field Station, Raufarhöfn, 3. Research Marine Centre of Santa Pola (CIMAR), University of Alicante, Spain

Kynnir / Presenter: Joana Micael

Botryllus schlosseri is a non-indigenous species (NIS) that is spreading along Reykjanes peninsula, SW-Iceland. On the western North-Atlantic coast this tunicate competes for space by overgrowing and smothering existing species which can lead to the destabilization of the ecosystem structure. This NIS could cause severe damage to shellfish aquaculture operations by excluding the settlement of the desired species, by overgrowing and suffocating young juveniles, or eliminating the flow of oxygen and particles through the mesh. For successful field control actions of this species, it is important to determine the temporal dynamic of its propagule. Keeping invasive species abundance below a density-dependent adverse effect, may be the most attainable goal for the management of this species. To provide insights into its reproductive strategy, colonies of B. schlosseri were collected during a 12-month period, in Sandgerði. The number of zooids, oocytes and larvae were counted, and the presence of ova or sperm was observed. This study revealed that the release of larvae is not even throughout the year, being more intense during the warmer months. In the light of the findings, it is now possible to determine the best time of the year to apply field actions to control B. schlosseri population density levels, optimizing resources for marine management.