| Warmer, oxygen-poor waters threaten world’s ‘most heavily exploited’ fish | |
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A new report using core samples taken from the seabed has determined that the Humboldt Current system off the coast of Peru was home to smaller fish during the last interglacial period, 130,000 years ago.
The conditions back then — with little oxygen content in the ocean and temperatures about 2°C (3.6°F) warmer than the average temperature in the current Holocene epoch — mirror those that scientists have predicted for 2100.
While many studies have argued that warmer water and lower oxygen lead to smaller fish, the added pressure of industrial fishing has made it difficult to determine the threat that climate change will pose on fisheries.
The Humboldt Current system is one of the most productive fisheries in the world, contributing to more than 15% of the global annual fish catch, so significant changes to this system will threaten food security. |
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In 2008, a team of researchers boarded an expedition vessel and set sail for the anchovy-rich waters off the coast of Peru. They were searching for a place to extract a sediment sample that would unearth secrets about the ocean from 130,000 years ago, a time when the planet was experiencing its last interglacial period. About 130 kilometers (80 miles) north of Lima, the researchers found an ideal spot; they bore into the seabed and drew out a 20-meter (66-foot) core sample. |
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