Discrete-event simulation of alga expansion

In the middle of the eighties, the French coast of the Mediterranean Sea (in the vicinity of Monaco) had been the initial site of the development of Caulerpa taxifolia, a tropical alga introduced by mistake. At the present time, this species has colonized several thousand acres of the French coast and has been detected at numerous points of the north-Mediterranean coast from Messina (Italy) to the Baleares Islands (Spain). Since the colonization of the French coast presented an impressive growth rate, and in order to forecast the development of Caulerpa, a simulation study was engaged. The purpose of the study is to evaluate Caulerpa propagation by means of an algorithmic computer model involving less restrictions than a mathematical model. This paper proposes the coupling of a Geographical Information System with a discrete-event simulation model that has to cope with incomplete data and sampling difficulties encountered in the hostile environment of the sea. This paper also presents an effort of collaboration between scientists of different disciplines.