Environmental Impacts of an Alien Kelp Species (Undaria pinnatifida, Laminariales) along the Patagonian Coasts

Undariapinnatifida(Harvey) Suringar was recorded in Argentina for the first time in December 1992. Since then, it shows an invasive and competitive behavior, spreading quickly from the initial focus and increasing its population density. The first individuals were found attached to the port of Puerto Madryn, suggesting that the vector of introduction was the ballast water of cargo ships arriving to Golfo Nuevo from overseas. Since U. pinnatifidawas recorded, it has been spreading along the Argentina coasts, extending its range within and outside Golfo Nuevo, along the coasts of Argentina from Puerto Deseado (Santa Cruz province) to Mar del Plata (Buenos Aires province) far as 1850 kilometers from each other. The invasive condition of this species creates an awareness of the effects inflicted upon the indigenous biodiversity of this region, as well as, on the commercially-important benthic community structure. Moreover, the detachment of subtidal algae, especially during the summer, and its deposition upon the beach, have altered the sedimentary balance along the overall transverse beach profile. This effect, in addition with algal extraction by trucks mainly during tourist seasons, may increase beach erosion processes along Patagonian coasts.Fil: Bunicontro, Maria Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires; ArgentinaFil: Marcomini, Silvia Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires; ArgentinaFil: Casas, Graciela Noemi. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; Argentin

Status, trends and drivers of kelp forests in Europe: an expert assessment

A comprehensive expert consultation was conducted in order to assess the status, trends and the most important drivers of change in the abundance and geographical distribution of kelp forests in European waters. This consultation included an on-line questionnaire, results from a workshop and data provided by a selected group of experts working on kelp forest mapping and eco-evolutionary research. Differences in status and trends according to geographical areas, species identity and small-scale variations within the same habitat where shown by assembling and mapping kelp distribution and trend data. Significant data gaps for some geographical regions, like the Mediterranean and the southern Iberian Peninsula, were also identified. The data used for this study confirmed a general trend with decreasing abundance of some native kelp species at their southern distributional range limits and increasing abundance in other parts of their distribution (Saccharina latissima and Saccorhiza polyschides). The expansion of the introduced species Undaria pinnatifida was also registered. Drivers of observed changes in kelp forests distribution and abundance were assessed using experts' opinions. Multiple possible drivers were identified, including global warming, sea urchin grazing, harvesting, pollution and fishing pressure, and their impact varied between geographical areas. Overall, the results highlight major threats for these ecosystems but also opportunities for conservation. Major requirements to ensure adequate protection of coastal kelp ecosystems along European coastlines are discussed, based on the local to regional gaps detected in the study