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this would not represent 15 species endemic to South Africa. A reserve system covering 29% of the coast would represent all of the species. Representing all species in the core regions of their ranges, a commonly stated conservation goal, would require 36% of the coast to be protected.

Bustamante et al., 1999:

Developed a design for a representative system of fully-protected zones for coastal habitats in the Galapagos Marine Reserve. This reserve covers the entire archipelago. Their objectives were to protect all of the ‘visiting sites' in the archipelago, areas of high biological importance, and to represent all the different coastal habitat types in each of the five biogeographic zones encompassed by the islands. To achieve this, they calculated it would be necessary to protect 36% of the coastline from fishing.

Halfpenny and Roberts, in review:

Designed a reserve system for the continental shelf seas of north-western Europe with the aim to represent all habitats and biogeographic regions present, and to replicate them in different reserves. Two systems covering 10% of the region were designed and were successful in achieving sufficient replication for most, but not all of the biogeographic regions and habitats.

OBJECTIVE: MAINTENANCE OF GENETIC VARIATION

Trexler and Travis, 2000:

Modeled the effects of fully-protected reserves to prevent or reverse undesirable selective effects of fishing, and promote genetic diversity. Found that, under the most likely selective regimes, a reserve covering just 1% of the management area would have marked conservation benefits. Benefits increased rapidly with the proportion of the area in reserves. A 10% reserve decreased directional selection by 60%, while a 20% reserve would eliminate the selective effects of fishing from the population entirely.

OBJECTIVE: INCREASE CONNECTIVITY AMONG RESERVES

Roberts, in review a:

Used a simple model in which reserve size and the fraction of the management area covered by reserves were varied to explore connectivity among reserves. Connectivity rapidly increased (= decreasing inter-reserve distances) as the proportion protected increased. For any given reserve proportion, connectivity also



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