In the only floristic study that has been done for the Port of Ensenada 37 macroalgae species were registered, those of which, clearly marked by their abundance are Ulva intestinalis, U. califonica, U. nematoidea and Sargassum muticum [10]. Since then, neither have results from recent research been presented nor any evidence for the possible ecological damage to native species. As part of a monitoring program of the marine flora from the Baja California Pacific coast, developed in our university to determine the possible mechanisms of introduction, dispersion and impact on the region’s benthonic
communities; in November of 2008, and March and June of 2010 newly established populations of macroalgae were found: Sargassum muticum and Sargassum ficicinum (Phaeophyta), Grateloupia turuturu and Grateloupia lanceolata (Rhodophyta) growing on intertidal rocks, on the hulls of ships and on different substrates at the facilities of Port of Ensenada, Baja California, Mexico. Due to the importance of these species, a basic study was proposed which would provide an updated list of the nonnative species of the Port of Ensenada, allowing through time to measure the possible impact on the native species of the area, to stimulate consciousness about the application of laws and guidelines both local and international and for regulation of the introduction of new species.