Pustaka Ilmiah Universitas Padjadjaran

Abstrak

Optimal Harvesting For A Predator–prey Metapopulation

All marine populations show some degree of spatial heterogeneity. Sometimes this spatial heterogeneity means that modelling the species as one single population is not adequate. For example, abalone, Haliotis rubra, has a discrete metapopulation structure with local populations connected by the dispersal of their larvae (Prince et al., 1987; Prince 1992). Brown and Murray (1992) and Shepherd and Brown (1993) argue that management for abalone should depend on the characteristics of local populations. Frank (1992) provides another example of the metapopulation structure. He points out that fish stocks, such as the cod of Iceland and West Greenland, which are separated by a large distance, and the two haddock stocks of the Scotian Shelf, are known to be strongly coupled by the dispersal of individuals. He also suggests that those stocks possess the ‘source/sink’ property described by Sinclair (1988) and Pulliam (1988), that is, persistence of the population in a sink habitat can be maintained by the migration from a source habitat. Source/sink habitat will be defined precisely in the next section. Furthermore, Frank and Leggett (1994) argue that the collapse of major fisheries such as North Atlantic Cod and Atlantic and Pacific Salmon, is due to the over-exploitation of the source population.