Gulf of Mexico Dead Zone Predicted for 2011

The Gulf of Mexico’s hypoxic zone is predicted to be the largest ever recorded due to extreme flooding of the Mississippi River this spring, according to an annual forecast by a team of NOAA-supported scientists from the Louisiana Universities Marine Consortium, Louisiana State University and the University of Michigan. The forecast is based on Mississippi River nutrient inputs compiled annually by the U.S. Geological Survey (USGS).

Scientists are predicting the area could measure between 8,500 and 9,421 square miles, or an area roughly the size of New Hampshire.  If it does reach those levels it will be the largest since mapping of the Gulf “dead zone” began in 1985. The largest hypoxic zone measured to date occurred in 2002 and encompassed more than 8,400 square miles.

Hypoxia is caused by excessive nutrient pollution, often from human activities such as agriculture that results in too little oxygen to support most marine life in bottom and near-bottom water. The hypoxic zone off the coast of Louisiana and Texas forms each summer and threatens valuable commercial and recreational Gulf fisheries. In 2009, the dockside value of commercial fisheries in the Gulf was $629 million. Nearly three million recreational fishers further contributed more than $1 billion to the Gulf economy taking 22 million fishing trips.

During May 2011 stream-flow rates in the Mississippi and Atchafalaya Rivers were nearly twice that of normal conditions. This significantly increased the amount of nitrogen transported by the rivers into the Gulf. According to USGS estimates, 164,000 metric tons of nitrogen (in the form of nitrite plus nitrate) were transported by the Mississippi and Atchafalaya Rivers to the northern Gulf. The amount of nitrogen transported to the Gulf in May 2011 was 35 percent higher than average May nitrogen loads estimated in the last 32 years.

The actual size of the 2011 hypoxic zone will be released following a NOAA-supported monitoring survey led by the Louisiana Universities Marine Consortium between July 25 and August 6.  Collecting these data is an annual requirement of the Mississippi River/Gulf of Mexico Watershed Nutrient Task Force Action Plan.

source: NOAA

NOAA Grant: Hypoxia in Chesapeake Bay

NOAA has awarded a team of researchers, led by the Smithsonian Institution, $634,047 as part of a planned five-year grant, estimated at nearly $1.6 million, to predict the impact of hypoxia on commercially and ecologically important finfish and oysters living in the shallow waters of the Chesapeake Bay.

Results of this study will help Bay area officials pinpoint key areas for habitat and fisheries restoration, and better protect shallow water habitat that serves a critical nursery function.

Hypoxia is a condition in which dissolved oxygen in the water becomes too low to support most life or compromises the growth, reproduction and immune responses of organisms. Although hypoxia can occur naturally, it is often worsened or caused by excess nutrients from human activities such as agriculture and the burning of fossil fuels. 

The research team, led by Denise Breitburg, Ph.D., of the Smithsonian Environmental Research Center, includes scientists from the University of Delaware and Louisiana State University who will collaborate closely with state and federal management agencies, including NOAA’s Chesapeake Bay Office, EPA’s Chesapeake Bay Program and Maryland’s Department of Natural Resources.

First-year funding has been awarded to the University of Delaware ($246,844), Louisiana State University ($74,834) and the Smithsonian Institution’s Environmental Research Center in Maryland ($312,369).

Report: Hypoxia in U.S. Coastal Waters

A report issued by key environmental and scientific federal agencies assesses the increasing prevalence of low-oxygen “dead zones” in U.S. coastal waters and outlines a series of research and policy steps that could help reverse the decades-long trend.

The interagency report notes that incidents of hypoxia (a condition in which oxygen levels drop so low that fish and other animals are stressed or killed) have increased nearly 30-fold since 1960, when data started to be collected.

The report was compiled by the National Oceanic and Atmospheric Administration and had significant inputs from the Environmental Protection Agency, the Department of Agriculture, the U.S. Geological Survey, and the Virginia Institute of Marine Science.

It provides a comprehensive list of the more than 300 U.S. coastal water bodies affected by hypoxia and, in eight case studies, highlights a range of representative ecosystems affected by hypoxia.

The USGS provided critical measurements and modeling of freshwater and nutrient delivery to coastal waters throughout the Nation.

The full release and report can be found at http://www.whitehouse.gov/administration/eop/ostp/nstc/oceans.

source: USGS