|
Is it the rich or the poor who overfish coral reefs? |
Unsustainable overfishing on coral reefs is not simply an issue of too many people fishing on the reefs. A new study shows that it is the level of socio-economic development of coastal communities that determines how intensively nearby reefs will be fished.
The American, Australian, British and Kenyan scientists behind the study surveyed 19 coral reefs and the adjacent coastal communities in the western Indian Ocean region. They measured the amount of fish on the reefs (fish biomass) and a range of social, economic, demographic and cultural indicators in the human communities. In a recent issue of the scientific journal Current Biology they publish their results showing that human population density in fishing villages was a rather poor predictor of the amount of fish in adjacent reefs. Rather it was the level of socio-economic development, such as access to water, paved roads and electricity, that was strongest correlated to fish biomass.
Actually, the authors found less fish on reefs in areas with moderate levels of socio-economic development. In contrast, the areas with the lowest and highest levels of socio-economic development had up to four times as much fish on the reefs.
Tackling poverty and managing fisheries
The findings of this study are consistent with the Environmental Kuznets Curve hypothesis (see fact-box), which predicts an inverted U-shaped relationship between environmental impact (e.g. overfishing) and economic affluence. The authors explain this relationship in their study in terms of changes in governance and technology that go hand in hand with socio-economic evolution.
At really low levels of socio-economic development reef exploitation may be limited by low-tech fishing gear and traditional social institutions such as customary taboo systems. In the other end of the spectrum, at high levels of development, greater economic diversity tends to reduce local fishing pressure and allow the targeting of distant offshore fisheries that are not part of reef ecosystems. Areas with medium levels of development, on the other hand, have access to engine-powered boats, spear guns, and other technologies that can rapidly deplete some fish species.
"In short, they have the technology to plunder their reefs, but not the institutions to protect them or the levels of development that allow for sufficient alternatives to fishing," says Josh Cinner, lead author of the study. "There are certainly some real challenges facing reefs, the path to their destruction is not inevitable. They can be sustained with the right combination of approaches, which includes promoting strategies such as fishery closures while at the same time tackling poverty as a root cause of the degradation of reefs and their fish stocks," Cinner concludes.
/Albert Norström
More at:Cinner, J. 2009. "Linking Social and Ecological Systems to Sustain Coral Reef Fisheries". Current Biology, Volume 19, Issue 3, 206-212 Box: Kuznets Curve:
 The Kuznets Curve is a graphical representation of the Russian-American economist Simon Kuznets's theory that economic inequality increases over time while a country is developing, then begins to decrease after a critical average income is attained. The argument for the environmental Kuznet's curve is based on the following: In a developing industrial economy, little weight is given to environmental concerns, raising environmental pollution byproducts. After attaining a certain standard of living from the industrial production system and when environmental pollution is at its greatest, the focus changes from self-interest to social interest. The interests give greater weight to a clean environment by reducing and reversing the environmental pollution that resulted from industrialization. This invereted U-shaped relationship occurs in the levels of some environmental pollutants released directly into the air or water, such as sulfur dioxide, nitrogen oxide, lead, DDT, and chlorofluorocarbons. However, there is little evidence that the relationship holds true for other pollutants as well as for greenhouse gas emissions, natural resource use or for impacts on biodiversity.
|
|
|
Sustainable Development Update (SDU), our newsletter on evironment - development issues, has become a News Blog. Read it here!
 |
|
|
