Man's Role in Changing the Face of the Ocean: Biological Invasions and Implications for Conservation of Near‐Shore Environments

Abstract: Human activities, primarily the global movement of organisms associated with ocean‐going vessels and with commercial fishery products, have lead to the redistribution of a vast number of marine organisms over the past five centuries. Most biological surveys postdated these transport events, so the distribution of many of these now cosmopolitan species has been interpreted as the result of natural processes, leading to underestimates of the role of humans in altering patterns of natural diversity and distribution of marine organisms along the coastal margins of the world Perceptions of the natural state of some systems versus their recent ecological alteration are illustrated by the National Estuarine Reserve Research System, within which many “natural” sanctuaries have been highly altered by exotic species The modern scale and rate of new human‐mediated invasions in the ocean are difficult to recognize due to the lack of communication among scientists working with different groups of organisms, different habitats, and different regions. Available evidence suggests that introductions continue unabated on a large scale throughout the world Despite the existence since 1973 of a number of international conventions to control the movement of exotic marine organisms adequate control still occurs largely at the regional and local levels.