Caribbean sardine collapse linked to climate change

[xchrom]

http://www.guardian.co.uk/global-development/2012/nov/07/caribbean-sardine-collapse-climate-change


A reduction in ocean upwelling, whereby nutrients are brought from the sea floor to the surface, is causing decreasing plankton levels. Photograph: Getty Images


The collapse of sardine fisheries in the southern Caribbean during the past decade may have been driven by global climate change, according to a study.

Researchers from the US and Venezuela linked ecological measurements in the southern Caribbean with global climate change indicators. These indices were revealed to correlate to changes in regional wind and seawater circulation patterns, which may have dire socioeconomic consequences for Caribbean countries – such as the collapse of valuable sardine fisheries.

The sardine, Sardinella aurita, feeds on plankton but since 2005 plankton levels in the Caribbean have reduced significantly, which, coupled with overfishing, may have contributed to the collapse of these fisheries. They have plummeted by as much as 87%, the study says.

The research team said the decreasing levels of plankton production are the result of a reduction in ocean upwelling, whereby nutrients crucial for plankton production are brought from the sea's floor to the surface. The drop in upwelling has, in turn, been driven by changes in wind patterns and wind strength, themselves driven by global climate change.

[AldoLeopold]

1. Yet another feedback

Not planned for or managed. These are the things that worry me. We know the seas will rise and the planet will warm.