MITECO concludes a demonstration experience for the control of the invasive exotic algae ‘Rugulopteryx okamurae’ in Ceuta

• This action, developed in collaboration with the Government of the Autonomous City of Ceuta and the Research Foundation of the University of Seville, reveals the impact of the presence of the algae on the biodiversity of the SCI Maritime-Terrestrial Zone of Monte Hacho
• Among the most outstanding results, a proposal for a control protocol for the invasive algae has been drawn up and more than 300 kg of this species has been collected

The Ministry for the Ecological Transition and the Demographic Challenge (MITECO) has completed a demonstration experience for the control of the invasive exotic algae Rugulopteryx okamurae in the Site of Community Importance (SCI) of the Maritime-Terrestrial Zone of Monte Hacho in Ceuta, within the framework of the LIFE INTEMARES project coordinated by the Biodiversity Foundation.
This invasive exotic species comes from Asia and in Spanish waters has undergone a strong expansion since its detection, precisely in Ceuta, in 2015.
The results of this action, which has had the collaboration of the Government of the Autonomous City of Ceuta and the Research Foundation of the University of Seville, have been presented this Thursday at a conference in which representatives of the Government of the City of Ceuta, MITECO and the Junta de Andalucía have participated. in addition to the organizations involved in the project and various scientific personnel, with the aim of informing sectors such as fishing and conservation, raising awareness of this problem and transferring the methodology so that it can be replicated in other areas of the Spanish coast affected by the invasion of Asian algae.
The main results of the experiment show an impact on native biodiversity in those areas of the rocky intertidal where R. okamurae is present.
However, the condition does not seem to have an impact on the populations of the ferruginous limpet (Patella ferruginea), listed as an endangered species by the Spanish Catalogue of Threatened Species.
Experience has also shown that the algae gradually recolonizes the eradicated areas of the intertidal, so it recommends executing the protocol annually with the aim of promoting the development and recolonization of native communities.
After the four actions carried out by the researchers within the framework of this pilot project over 12 months, a total of 308.67 kg of this invasive algae have been removed from the intertidal zone.
As a result of this action, it has been verified that the species Anemona sulcata and Paracentrotus lividus have been directly benefited in the area where the work has been carried out.
It should be noted that these species have almost entirely disappeared from the infracoastal area of Ceuta, after the invasion of Rugulopteryx okamurae, so the last strongholds of their populations are currently settled in the intertidal strip, mostly in the pools or tidal pools.
Likewise, during the present study, specimens of Rugulopteyx okamurae settled on the protected species Dendropoma lebeche have been eliminated and, therefore, this species has also benefited directly from this project. CONTROL PROTOCOL Among the works carried out, a proposal for a protocol for the control of invasive algae has been drawn up based on the National Strategy for the control of Rugulopteryx okamurae algae in Spain, approved in 2022.
It has been designed by the Marine Biology Laboratory of the University of Seville (LBM-US) and the Strait of Gibraltar Marine Biology Station (Ceuta).
The editorial staff has also had the support of the technical staff of OBIMASA (Works, Infrastructures and Environment of Ceuta S.L.), who have also participated in the monitoring of the progress of the project. In this line, a methodology has been obtained with which to estimate the economic and labor effort for the replication of the protocol in other areas of the Spanish coast affected by the invasion of the Asian algae.
In addition to limiting the advance of Rugulopteryx okamurae, the protocol has focused on the analysis of the impact of the species and the minimization of the pressures it exerts on the ecosystem and the native species that develop in it. EXPANSION OF THE INVASIVE EXOTIC ALGAERugulopteryx okamurae arrived on the French Mediterranean coasts in 2002.
Currently, it is present in various parts of the Mediterranean Sea and the Atlantic Ocean, such as Morocco, Spain, France and Portugal, showing a clearly competitive and expansive behavior.
In 2015, the Autonomous City of Ceuta suffered a massive occupation of the seabed of its coastal area and its beaches, in the form of large landslides.
Since then it has become the most abundant species on the coasts of Ceuta from the surface to 30 meters deep, which has implied alterations in the structures of shallow and deep communities, and also in the part of the emerged coastline.
Hundreds of tons of the algae accumulate on beaches and spread in the water column, becoming a nuisance with implications for tourism, fisheries and biological communities.
The dispersion of this algae in the Iberian Peninsula has reached the Levantine coast, from Alicante to the province of Girona. LIFE INTEMARES The LIFE INTEMARES project advances towards the objective of achieving an effective management of the marine areas of the Natura 2000 Network, with the active participation of the sectors involved and with research as basic tools. The Biodiversity Foundation of the Ministry for Ecological Transition and the Demographic Challenge coordinates the project. The ministry itself, through the Directorate-General for Biodiversity, Forests and Desertification; the Regional Government of Andalusia, through the Ministry of Sustainability and the Environment, as well as the Environment and Water Agency; the Spanish Institute of Oceanography of the Spanish National Research Council; AZTI; the University of Alicante; the Polytechnic University of Valencia; the Spanish Fisheries Confederation; SEO/BirdLife and WWF Spain. It is supported by the LIFE Program of the European Union.