NEW ORLEANS » This summer’s low-oxygen "dead zone" in the Gulf of Mexico is bigger than average, but doesn’t approach record-size as scientists had predicted.

Scientists led by Nancy Rabalais of the Louisiana Universities Marine Consortium say the area covers 5,840 square miles of the Gulf floor. The dead zone has so little oxygen that water at the sea floor can’t support fish, shellfish and other aquatic life in a condition known as hypoxia.

Scientists had expected a wet spring to bring more nutrients than usual down the Mississippi River, leading to a dead zone that approached the biggest-ever. The largest dead zone on record was in 2002, when it spread across 8,481 square miles of the Gulf.

Rabalais says temperature and salinity measurements indicate high winds in early to mid-July mixed oxygen into deeper waters.