Andrew Cohen directs the Center for Research on Aquatic Bioinvasions in California. He used his Pew fellowship to research, identify, and report on the patterns and effects of invasive species in tropical coastal waters in the Caribbean, including the western tropical Atlantic, the Atlantic and Pacific coasts of Panama, and the eastern Pacific Ocean. Through his research, Cohen documented new appearance records in the area for a number of exotic organisms and many species of unknown origin. He identified new appearances of three species in the Western Atlantic, three on the Pacific coast of Panama, and at least 10 on Panama’s Atlantic coast. Many of the organisms Cohen identified typically build up on dock pilings, seawalls, buoys, and other artificial substrates in harbors and bays. However, Cohen also found some species on natural structures, including mangrove roots, rocks, shells, and coral. Vessel hulls were identified as the most common way invasive species were transported to the region in or before the 19th century. Cohen suggests from the heavy ship hull fouling he encountered that this mechanism of transport continues to be important in the tropics, both by transport between major bioregions of the world (including from ships crossing the Panama Canal and encountering freshwater during the transit) and by shorter intra-regional trips. Aquaculture and ballast water, however, have become increasingly important modes of transmission for exotic species in this region over the past several decades.
To learn more about Cohen, visit his bio online: http://bioinvasions.org/wp-content/uploads/Dr.-Andrew-Cohen.pdf.