Biologists view Protected Areas (PAs) as natural areas established and managed primarily for the conservation of nature. However, many early Pas were established for aesthetic or socio-economic reasons and received little scientific input to their design. More recently, scientists have identified gaps in PA networks and various contemporary PAs have been established to provide for habitats and species in need of protection.
Scientists have also modelled minimum areas and population sizes that should be protected to prevent extinctions arising from demographic or chance causes. However, these theoretical ideals are difficult to put into practice, particularly as PAs increasingly face more immediate external threats. If scientists are to influence future PA design, and if PAs are to succeed in the long term, these concepts must be applied in practice. Therefore, sufficient protection must be integrated with human needs and aspirations in the design of future protected areas.
The threat posed to coral reefs by biological invasion is unlikely to diminish and should therefore be considered in analyses of the effectiveness of Marine Protected Areas.Resource Type: Journal Papers
Global and regional coral reef area statistics are of considerable value in fields ranging from global environmental change to fisheries to conservation. Although widely quoted, Smith's 1978 figure of 600 000rkm2 is only an approximate calculation. The World Conservation Monitoring Centre has prepared a new estimate of reef coverage by mapping emergent reef crest and very shallow reef systems. These data were rasterised, using 1rkm grid squares, as a means of reducing errors arising from variation in scale. Global and regional reef coverages were calculated from the resultant grid. The total global area is estimated at 255 000rkm2, considerably lower than many previous estimates. Variation in reef area estimates is, in part, a function of variation in reef definition.Resource Type: Journal Papers
The countries affected by the 2004 Asian tsunami contain the most diverse and extensive coral reefs and mangroves of the Indian Ocean, and some of the richest in the world. Not only are these ecosystems among the most threatened in the world, they also provide numerous essential ecosystem services.
It is thus not surprising that reefs and mangroves received widespread attention after the tsunami, with three principal questions posed: Are the tsunami's impacts on reefs and mangroves a further threat to their future survival? Did reefs and mangroves play a role in shoreline protection and reduce structural damage and human mortality? How could reconstruction efforts include actions to maintain these ecosystems and reduce further threats to them?Resource Type: Journal Papers
Coral reefs are the most biologically diverse of shallow water marine ecosystems but are being degraded worldwide by human activities and climate warming. Analyses of the geographic ranges of 3235 species of reef fish, corals, snails, and lobsters revealed that between 7.2 and 53.6 of each taxon have highly restricted ranges, rendering them vulnerable to extinction. Restricted-range species are clustered into centers of endemism, like those described for terrestrial taxa. The 10 richest centers of endemism cover 15.8 of the world's coral reefs (0.012 of the oceans) but include between 44.8 and 54.2 of the restricted-range species. Many occur in regions where reefs are being severely affected by people, potentially leading to numerous extinctions. Threatened centers of endemism are major biodiversity hotspots, and conservation efforts targeted toward them could help avert the loss of tropical reef biodiversity.Resource Type: Journal Papers
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