A recent article published in the journal Science by members of the History of Marine Animal Populations (HMAP) field project of the Census of Marine Life Program indicates that while degradation has been occurring in coastal ecosystems due to human influence since Roman times, it can actually be shown that that decline has significantly accelerated in the last 150-300 years. Specific results from the 12 major estuaries analyzed show that since the emergence of written historical records, 65% of wetland and seagrass habitats have been destroyed, water quality has decreased significantly, and 90% of marine species have disappeared. This is all due to human influence.
It is well known that estuaries and coastal areas have played a critical role in human development. They serve as a habitat for most of our commercial fish catch, a resource for our economy, and a buffer against natural disasters. Yet, these once rich and diverse areas are severely impaired world-wide. Surprisingly, all 12 of the estuarine areas included in the study exhibited similar trends of ecological degradation as well as similar trends in the magnitude of that degradation over the past 150-300 years. However, when compared to other ocean ecosystems such as coral reefs, they have received little attention in the press, and are not commonly on the national policy agenda.
The four-year study utilized a new method of synthesizing diverse data from such disciplines as archaeology, paleontology, history, fisheries, and modern ecology. This has allowed the researcher to construct continuous timelines of change in the estuaries under investigation. While the findings state that the primary cause of the degradation of these estuarine environments is human exploitation, it provides both baseline data and quantitative targets that may allow for future sustainable management of these important ecosystems. A positive outcome from the study shows that these environments do respond to restoration efforts. Combinations of mitigation measures such as controlling habitat destruction, resource exploitation, and pollution have proven successful in 78% of restoration efforts.
The full article, entitled "Depletion, Degradation, and Recovery Potential of Estuaries, and Coastal Seas," is available in Science, Vol. 312, June 2006.