Results suggest that the loss of biodiversity in coastal ecosystems has led to the impairment of critical ecosystem services, such as the filtering services provided by suspension feeders and submerged vegetation that contribute to the maintenance of high water quality. The authors also used the United Nations Food and Agriculture Organization’s global catch database for the period from 1950 to 2003 to examine relationships between biodiversity and ecosystem services in 64 large marine ecosystems (greater than 150,000 square-km).

This analysis revealed that 29 percent of all fished species had collapsed by 2003 and ecosystems with the fewest species suffered the greatest rates of collapse. The authors note that large marine ecosystems with higher species diversity also recovered more quickly following periods of overexploitation, perhaps due to the improved abilities of fishers to switch among species, thus giving overexploited species the opportunity to recover. Finally, the authors examined relationships between biodiversity and ecosystem services in 44 marine reserves and four large-scale fisheries closures. On average, these regions had species richness 23 percent greater than non-protected areas. Tourism revenue, measured as the number of dive trips, also was increased in these areas, suggesting that not only do diverse marine fisheries serve as major global food sources, but they also provide opportunities for recreation.

The authors conclude that the loss of marine biodiversity is negatively impacting the marine ecosystem services on which we depend. Yet they believe the trend is reversible and, therefore, urge the restoration of biodiversity through careful management of fisheries, maintenance of pollution-free habitats, and creation of marine reserves.