Protection targets

With increasing global environmental degradation calls for 'protection targets' are being made more frequently. For example the 4th World Congress on National Parks and Protected Areas in 1993 advised that 10% of each biome receive protection. Likewise, the 1st Symposium on Marine Conservation Biology in 1997 called for an increase in the number and effectiveness of MPAs so that 20% of all nations' Exclusive Economic Zones and the High Seas be protected by the year 2020. One problem with such recommendations for marine ecosystems is that the data have not been available to calculate the quantity protected and to estimate when targets for protection have been reached.

 

Another is that the sea receives very different treatment to land in terms of conservation. While most people accept that some terrestrial habitats should be protected, they feel the sea should be open to exploitation. Theoretical modelling work suggests that protecting 20-50% of the sea from fishing will greatly reduce the risks of overexploitation and fishery collapse, and would be likely to substantially increase long-term yields of over-exploited species.

 

This level of protection represents a long-term target. In reality marine protection starts from very small areas. At Anse Chastanet, St. Lucia, a small (2.6 ha) reserve was established by a hotel as a safe haven for snorkellers. Within three years the biomass of commercially important fish species, especially predatory snappers (Lutjanidae) a group highly vulnerable to the effects of over-fishing, was more than double that present in adjacent areas of similar habitat. Species such as the highly mobile mutton snapper (Lutjanus analis), Spanish grunt (Haemulon macrostomum) and Black Margate (Anisotremus surinamensis) were found nowhere else along the coast. So even small reserves can be very effective but globally many more are needed.