Marine exotic species in the cold temperate harbors of Argentina

E SCHWINDT; RAFFO MP; TATIAN M; ORENSANZ JM; ALONSO G; BORTOLUS A; DIEZ ME; DOTI B; GENZANO G; LAGGER C; LOPEZ GAPPA, J. L.; LOVRICH G; PIRIZ ML,; SAVOYA V; SUEIRO MC; ZELAYA D

Mar del Plata

Congreso; 2nd World Conference on Biological Invasions and Ecosystem Functioning; 2011

Grieta

Shipping moves over 80% of the world’s commodities and transfers 3 to 5 billion tonnes of ballast water each year worldwide. Given that harbors are the main entrance for marine exotic species, their close surveillance is essential to optimize the design of effective management and prevention strategies. A recent literature review reported high number of aggressive invasive species along the southwestern Atlantic coast, in Argentina. In this work we coordinated the first exhaustive qualitative and quantitative survey of the six most important cold temperate marine harbors of Argentina (40º-54ºS) in order to (a) make an up-to-date list of exotic and cryptogenic species, (b) detect new introductions and (c) document range extensions of known introductions. Qualitative samples of the fouling species (n = 3-6 per harbor, size = 25x25 cm) were obtained by scraping the surface of the pilings. Quantitative data of the fouling species were obtained with plates (n= 15 per harbor, same size) deployed at each harbor during two years. We found more than 200 species; ten of which were exotic species and nine cryptogenic species (including three new records). Three of the exotics are new records and other three showed range expansions towards high latitudes. Most of these species were found in San Antonio Este harbor (40ºS). We combined these results with previous analyses of maritime traffic, oceanographic, meteorological, ecological and anthropogenic variables per harbor in order to speed up the development of early-detection plans and monitoring strategies focusing on the most important harbors region wide.