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- Non-indigenous species in Portuguese coastal areas, coastal lagoons, estuaries and islandsPublication . Chainho, Paula; Fernandes, António; Amorim, Ana; Ávila, Sérgio P.; Canning-Clode, João; Castro, João J.; Costa, Ana C.; Costa, José Lino; Cruz, Teresa; Gollasch, Stephan; Grazziotin-Soares, Clarissa; Melo, Ricardo; Micael, Joana; Parente, Manuela I.; Semedo, Jorge; Silva, Teresa; Sobral, Dinah; Sousa, Mónica; Torres, Paulo; Veloso, Vera; Costa, Maria JoséTrends in abundance, temporal occurrence and spatial distribution of marine and brackish non-indigenous species (NIS) are part of the indicators to assess the compliance of Good Environmental Status in the European Marine Strategy Framework Directive (EU-MSFD). European-wide regional and national databases for NIS will be useful for the implementation of the EU-MSFD but there are still spatial gaps for some regions and taxonomic groups. In 2009, Portugal was among the countries with the lowest reported numbers of NIS in Europe and a national online database on NIS was not available. This study provides an updated list of NIS registered in Portuguese coastal and estuarine waters, including mainland Portugal and the Azores and Madeira archipelagos. A list of 133 NIS was cataloged, most of which recorded in the last three decades, showing that this area of the North Atlantic is no less prone to introductions than neighboring areas. Most NIS reported in the current inventory are native in the Indo-Pacific region. Fouling and ballast water are the most likely introduction vectors of NIS in the studied area but shipping routes connecting to the NIS native regions are rare, indicating that most species are secondary introductions. The high number of NIS in the Azores and Madeira islands indicates that this ecosystem type seems to be more susceptible to invasions but these preliminary results might be biased by a higher number of studies and knowledge on the NIS occurrence on the islands.
- Abundance, seasonal patterns and diet of the non-native jellyfish Blackfordia virginica in a Portuguese estuaryPublication . Marques, Filipa; Chainho, Paula; Costa, José Lino; Domingos, Isabel; Angélico, M.M.Blackfordia virginica, a non-indigenous hydrozoan introduced in many systems around the world, has been observed in the Mira estuary, southwest of Portugal, since 1984. Monthly sampling (January 2013–January 2014) at a fixed location with high abundance of the medusae confirmed the occurrence of a seasonal cycle associated with temperature and photoperiod. The beginning of the medusa cycle occurred in May immediately after the spring zooplankton bloom during April. Examination of the gut contents of B. virginica medusae revealed that copepods, the most abundant group in the zooplankton community, were highly predated. Barnacle nauplii, decapod crustacean larvae and anchovy eggs were also identified in the guts. The medusae showed positive selection for copepods, and negative selection for barnacle nauplii, decapod crustacean larvae and anchovy eggs. The mortality rate of copepods (used as a model prey group) induced by medusae predation was estimated and showed the potential impact of this species in the ecosystem, ranging between 2.34 d−1 and 0.02 d−1, with a minimum copepod half-life of 0.30 days.