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Based on published distribution maps of 15 key fish species, foraging areas of three top predators during their breeding season, and fishing grounds of the main commercial fleets in the southern Benguela ecosystem, seven spatialized ecosystem indicators are derived: biodiversity, connectivity, mean ratio of fished area and area of distribution by species, exploited fraction of the ecosystem surface area, total catch per fished area by fishery, mean bottom depth of catches, and mean distance of catches from the coast. These indicators are compared and their suitability for an ecosystem approach to fisheries is discussed. The first two indicators characterize the ecosystem; the others are pressure indicators that are also compared with conventional (catch rate) indices of abundance.

With 10 figures in the text)The stomach contents of 1522 adult seals (Arcrocephalus pusillus pusillus) and 673 pups, which were collected around the West and South Coasts of Southern Africa, were examined and cephalopod prey identified. About 20 cephalopod species (some identifications were uncertain) were found in the stomachs, of which only six were significant: Loligo vulgaris reynaudii, Sepia spp., Octopus sp., Todaropsis eblanae, Todarodes angolensis and Ocythoe tuberculara. This list suggests that A. pusillus feeds exclusively on the continental shelf, frequently on or near the bottom. Among adults, cephalopod prey varied in importance around the coast. It was most important on the South Coast of South Africa where it comprised 35.0% of the weight of all prey, ofwhich L. o. reynaudiiconstituted about 88%. On the West Coast cephalopods comprised about 26.6% by weight of all prey, and ocropus sp. predominated, whereas in Namibian waters cephalopods were least important, constituting only 3.4% by weight of all prey, with Todurodes angolensis and Octopus sp. being most significant. Among pups (aged 8-10 months) in the Liideritz (Namibia) area, cephalopods were about 16.9% of prey by weight, of which Ocyrhoe tuberculata, small Sepia spp. and Octopoda were most important.