Early detection of marine invasive species following the deployment of an artificial reef: Integrating tools to assist the decision-making process.

Early detection and rapid response plans are a set of principles to reduce the establishment, spread and impact of invasive species and it is a critical step in management in marine ecosystems. Two potentially invasive ascidians attached to the hull of a recently sunk fishing vessel were early detected in Patagonia. With the aim of assisting in the management decision-making process during the early steps of a rapid response, we conducted several analyses through different approaches. First, we identified the species through classic taxonomical and genetic analyses. Then, we evaluated the regional and international shipping connectivity to study potential donor regions and finally, we used species distribution models (SDMs) to predict the potential distribution of these species. The potentially invasive ascidians were identified as Styela clava and Styela plicata, and this is the first record for both species in the Nuevo gulf, Patagonia Argentina. Both species have a widespread distribution around the world with strong ecological and economic impacts documented. Shipping traffic analysis suggested that S. plicata could have arrived by secondary spread from regional ports, while the arrival of S. clava was likely to be associated with international shipping traffic. Furthermore, the SDM predicted that S. clava has suitable coastal areas along the entire Southwestern Atlantic shoreline, where it is currently absent. On the contrary, the SDM predicted that further southward spread of S. plicata is unlikely, being limited by the minimum annual temperature. We discussed the different approaches, tools, and expertise integrated in this work in the light of the decision-making process for the early detection of marine invasive species in the Southwestern Atlantic. Moreover, we call attention to the increased creation of artificial habitats through the intentional sinking of ships and the potential consequences of these actions in the conservation of marine ecosystems.

Assessment of the efficiency of controls to prevent biologic invasions at the San Lorenzo Port, Argentina.

The problem created by invasive non-native species through ships' ballast water has caused the International Maritime Organization (IMO), through the Ballast Water Management (BWM) Convention and many countries to develop their own laws to prevent their introduction. One of the most important non-native species in Argentina, the golden mussel (Limnoperna fortunei), causes a significant economic impact on the Plata Basin. Argentina has a great amount of maritime and fluvial ports that receive ships from different regions of the world. Particularly, the San Lorenzo-San Martín Port Complex (here termed SLOR), placed in the terminal portion of the Paraná Basin, receives ocean ships with great loading capacity, which increases the possibility of invasions and the need of an adequate environmental management. This work proposes to estimate the potential vulnerability of SLOR port, in relation with the origin of the ballast water and its volume. For this purpose, an adaptation of the risk assessment model of the GloBallast Program was used. The results suggest that SLOR has important similarities with different fluvial ports of the world, especially in Brazil and China. However the amount of ships coming from the nearest estuary waters, where the diversity of invasive species has major effects, is also important. This article provides the necessary information to conduct the efforts through surveys and enforcement regulations, and could be the foundation for future research using global data that could provide basic information for other fluvial ports with similar features.

Integrated ecotoxicological assessment of bottom sediments from the Paraná basin, Argentina.

Paraná River, the six largest in the world, is receptor of pollution loads from tributaries traversing urban and industrialized areas, and extensive agriculture, particularly in its middle and low stretch along the Argentinean sector, where most of the productive activities of the country develop. Within the frame of monitoring surveys, the quality of bottom sediments from distal positions of twenty tributaries and three of the main course was evaluated. The assessment covered testing lethal and sublethal effects with the Hyalella curvispina based toxicity test, a benthic macrofauna survey and physicochemical variables of sediment matrix composition. A multivariate statistical analysis approach permitted integrating the obtained data from the different survey lines of evidence, explaining potential causes of the measured biological effects. The main perturbations detected were associated to tributaries in the middle sector of the basin, where anoxic conditions with high sulfide contents prevail mostly related to organic matter inputs of diverse combined activities, where sediments induce high lethality, and a consequent strong reduction of the benthic community population and diversity. The integrated survey approach proved being a robust tool in the assessment of causative-adverse effects relationships.