Scientists say this year’s dead zone in the Gulf is smaller than expected.
This year’s hypoxic zone measured about 4400 square miles, less than the 5600 square miles the anticipated in the spring.
But that’s still almost 2.8 million acres of Gulf potentially unavailable to fish and bottom species.
The size of the gulf hypoxia zone changes depending on the amount of rain received in the Mississippi River Basin - The Mississippi River discharge this year was below the summer average.
The Gulf dead zone forms each spring and summer off the Louisiana and Texas coast when oxygen levels drop too low to support most life in bottom and near-bottom waters.
The zone is caused by nitrates and nitrogen from fertilizer and urban runoff flowing down the Mississippi River.
When the excess nutrients reach the Gulf, they stimulate an overgrowth of algae, which eventually die and decompose, depleting oxygen as they sink to the bottom.
The resulting low oxygen levels near the bottom of the Gulf cannot support most marine life.
Fish, shrimp and crabs often swim out of the area, but animals that are unable to swim or move away can be stressed or killed.
The amount of nitrogen entering the Gulf each spring has increased by about 300 percent since the 1960s, mainly due to increased agricultural runoff.
This year’s hypoxic zone measured about 4400 square miles, less than the 5600 square miles the anticipated in the spring.
But that’s still almost 2.8 million acres of Gulf potentially unavailable to fish and bottom species.
The size of the gulf hypoxia zone changes depending on the amount of rain received in the Mississippi River Basin - The Mississippi River discharge this year was below the summer average.
The Gulf dead zone forms each spring and summer off the Louisiana and Texas coast when oxygen levels drop too low to support most life in bottom and near-bottom waters.
The zone is caused by nitrates and nitrogen from fertilizer and urban runoff flowing down the Mississippi River.
When the excess nutrients reach the Gulf, they stimulate an overgrowth of algae, which eventually die and decompose, depleting oxygen as they sink to the bottom.
The resulting low oxygen levels near the bottom of the Gulf cannot support most marine life.
Fish, shrimp and crabs often swim out of the area, but animals that are unable to swim or move away can be stressed or killed.
The amount of nitrogen entering the Gulf each spring has increased by about 300 percent since the 1960s, mainly due to increased agricultural runoff.
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