| Summary: | Multi-site Leslie matrices for sub-divided populations are explored with respect to optimization of management goals and transient dynamics associated with implementing actions to achieve those goals. The management goals explored were minimizing the cost associated with controlling a pest species (Yellow Legged Herring gull, Larus cachinnans), and maximizing the yield from a commercially valuable species (Artco-Norwegian cod, Gadus morhua). Transient dynamics were evaluated for a representative r- and K-selected species, and time to convergence was compared between one-site versus multi-site models, and for different migration patterns, migration levels, and proportion of the population migrating. In a density-independent model for the Yellow Legged Herring Gull, the most efficient control technique was to focus management actions on the better quality sites, because breeders at high quality sites had higher expected life-time reproductive values. The amount of harvest required to maintain equilibrium was a function of site quality and the balance between immigration and emigration-cost (and effort) increased as dispersal favored better quality sites. Given a choice between destroying eggs or culling adult breeders, culling required ten times less effort per-capita and would be the optimal strategy as long as per-capita culling cost is no more than ten times greater than the per-egg destruction cost. A density-dependent model of Arcto-Norwegian cod revealed that the theoretical yield was maximized from harvesting age 6 individuals. If only the minimum age harvested could be controlled, then the constrained yield was maximized from harvesting ages five and older. Yields were compared between a reserve model with 25% of fishing area closed and a no-reserve model. Yields in the reserve model exceeded the non-reserve model when transfer rates out of the reserve were higher, when higher fecundity was realized in the reserve (which could result from improved habitat quality), and when fishing rates in the non-reserve ...
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