The Northern Gulf of Mexico Dead Zone

Alan Lewitus, Supervisory Oceanographer, NOAA Centers for Coastal Ocean Science

The northern portion of the Gulf of Mexico ecosystem, which contains almost half of the nation's coastal wetlands and supports commercial and recreational fisheries which generate billions of dollars annually, has undergone profound changes due to nutrient enrichment of Mississippi River water from land-based sources. This over-enrichment of nutrients stimulates the development of seasonal hypoxia (very low oxygen waters) over the Louisiana/Texas continental shelf in summer and results in the largest recurring hypoxic zone (aka “Dead Zone”) in the United States. Hypoxic waters can cause habitat loss, stress and even death to marine organisms; affecting commercial harvests and the health of impacted ecosystems.

This issue has become a focal point for considerable scientific and policy attention because of the hypoxic zone’s enormous size and implications for watershed management for more than 40% of the contiguous United States.  I will present a historical perspective of research into the causes and ecosystem impacts of the Dead Zone, and of the attempts of an interagency Task Force (federal, state, and tribes) to fix the problem.


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About the Presenter: 

Alan Lewitus is a Supervisory Oceanographer at the NOAA National Ocean Service (NOS) National Centers for Coastal Ocean Science (NCCOS) Center for Sponsored Coastal Ocean Research (CSCOR).  He serves as Branch Chief for the Ecosystem Stressors Research Branch of CSCOR and oversees competitive programs in hypoxia, harmful algal blooms, and sea level rise.  Since joining NOAA in October 2005, Dr. Lewitus has been closely involved in activities related to research and management of the Gulf of Mexico ecosystem, including coordinating and facilitating efforts to mitigate the northern Gulf hypoxic zone (aka “Dead Zone”).  He is a member of the NOAA Gulf of Mexico Regional Collaboration Team, is co-Chair of the Gulf Alliance Water Quality Team Harmful Algal Bloom Work Group, and a NOAA representative to the Gulf Hypoxia Task Force (as Coordinating Committee member) and the Eastern Tallgrass Prairies and Big Rivers Landscape Conservation Cooperative (as Steering Committee member).  

His background is in phytoplankton ecology and physiology, with research interests that include coastal eutrophication, the ecology of harmful algal blooms, microbial food web dynamics, and the role and measurement of phytoplankton pigments, and he has over 90 peer-reviewed publications on these subjects.  Prior to joining NOAA, Dr. Lewitus held a joint position with the University of South Carolina and SC Department of Natural Resources as Director of the SC Algal Ecology Laboratories and SC Harmful Algal Bloom Program.  He holds a BA from Rutgers University, a MS degree in Marine Sciences from Moss Landing Marine Laboratories with a Physical Oceanography discipline, and a PhD in Biological Oceanography from the MIT/Woods Hole Oceanographic Institute joint program.



About the Teach-In

The National Biodiversity Teach In is a webinar series for classrooms designed to bring awareness to the importance of biodiversity. Created by Deb Perryman’s AP Environmental Science Class at Elgin High School in response to the story of Martha, the last passenger pigeon, the goal is to bring stories of biodiversity to classrooms and individuals around the globe.

Originally conceived as a week-long event, this year the Teach-In will take place every Friday in February. Friday, February 12th will be presented by EarthEcho International with a day of ocean themed webinars, featuring Philippe Cousteau Jr. at 12pm CST.  

View the full schedule for February 12th >> 
Learn more about the Teach In >>