Arrival and proliferation of the invasive seaweed Rugulopteryx okamurae in NE Atlantic islands

Abstract

The present study reports the recent occurrence and expansion of Rugulopteryx okamurae in the Azores archipelago (NE Atlantic). Morphological and molecular characters confirmed the species identification. Quick surveys around the island of São Miguel showed that it has successfully colonized the island and is quickly expanding. In some locations, R. okamurae is currently the dominant organism smothering all other benthic biota and posing a serious threat to the benthic ecosystems across the region. The species first record dates from 2019 near the main harbour of the island, suggesting that its introduction was driven by human-assisted transport, via boat ballast waters or adhered to ship hulls and likely originating from the Mediterranean populations that have been proliferating in recent years across the Strait of Gibraltar.

A Concise Review on the Potential Applications of Rugulopteryx okamurae Macroalgae

“…Its invasive character was confirmed in the region with replacement of the native biota and an occupancy rate that reached almost 100% in some locations. Furthermore, in May 2021, algal substrate accumulation was reported on beaches of Faial Island [ 7 ]. The species appeared in São Miguel Island with the same accelerated colonization as in the Strait of Gibraltar, with intense proliferation and habitat domain [ 7 , 16 ].…”

“…Furthermore, in May 2021, algal substrate accumulation was reported on beaches of Faial Island [ 7 ]. The species appeared in São Miguel Island with the same accelerated colonization as in the Strait of Gibraltar, with intense proliferation and habitat domain [ 7 , 16 ]. In Azores, significant changes in the structure of shallow-water marine benthic communities have already been noticed, with a significant absence of diversification of native species, which ratifies the invasive character of this alga [ 7 ].…”

“…The brown macroalga R. okamurae is one of the most recently identified non-native invasive species. This invasive nature was detected in France, in the Strait of Gibraltar (Ceuta and Tarifa) and in the São Miguel Island (Azores) [ 7 ], together with other oceanic islands. The implications resulting from the massive invasion of this species are significant and involve several spheres.…”

Turning an invasive alien species into a valuable biomass: Anaerobic digestion of Rugulopteryx okamurae after thermal and new developed low-cost mechanical pretreatments

“…Since then, it has widely spread through the Mediterranean Sea, being the Strait of Gibraltar the most affected area (El Aamri et al, 2018;Sempere-Valverde et al, 2021). Moreover, recently, it has been observed in the Azores archipelago located in the Atlantic Sea (Faria et al, 2022).…”

The invasive brown seaweedRugulopteryx okamurae(Dictyotales, Ochrophyta) continues to expand: first record in Italy

“…The first record as an invasive species was on the Spanish coast of the Strait of Gibraltar in 2016 (Altamirano et al 2016, 2017), on the African coast (Ceuta, Spain) and then on the European coast. Since then, the species has been spreading both towards the Mediterranean Sea and the Atlantic Ocean, being already present other than in Spain (Altamirano et al 2016; García Gómez et al 2020), in Morocco (El Aamri et al 2018), Portugal (Liulea et al 2023) and France (Ruitton et al 2021), having even reached different Macaronesian islands such as the Azores (Faria et al 2021), Madeira (Bernal-Ibáñez et al 2022) and the Canary Islands (REDEXOS 2022). Its limit in the Mediterranean is currently found on the coast of Marseilles, in France (Ruitton et al 2021).…”