   | 
• Climate in the Gulf
• The Report
• For Teachers
• Overview
• Slow the Change
• Speed our Response
• Overview
• Water Resources
• Sea-Level Change
• Human Perspectives
| | Alabama
Fisheries
In the sounds, bays and estuaries behind the small number of barrier islands separating the Alabama mainland from the Gulf of Mexico, fresh and salt water combine to create the environment that shrimp and oysters need to live and flourish. The state's aquaculture industry—fifth in the nation in producing food fish, baitfish, shrimp, and oysters—is vulnerable to climate change in a number of ways:
- If freshwater flow into Mississippi Sound, or Mobile and Perdido Bay permanently declines due to climate change, then higher salt concentrations, less nutrient input, and less frequent flushing would result in lower water quality overall. Salt tolerance of some species in marshes, mangroves, and seagrass beds may be exceeded, causing changes in the food web and possibly a reduction in fish growth and fishery yields.
 If wetlands can migrate inland as sea level continues to rise, the yield of estuarine-dependent fisheries, such as shrimp, will increase or decrease over time depending on the size and quality of the new habitat over time.
- Mobile Bay already experiences periods during which oxygen is significantly reduced in coastal waters—a condition called hypoxia and known locally as 'jubilee.' Hypoxia is the result of fresh water flowing into the ocean, causing an influx of nutrients and the stratification of Bay waters (the development of distinct layers, with heavier saltwater beneath and lighter fresh water on top). Should runoff into the Bay increase with climate change, the size or frequency of this naturally occurring event could increase. The resulting "dead zone" would affect Alabama's fisheries, especially shrimp, whose yield typically declines during hypoxic events.
Photo Credits:
Alabama Canebrake pitcher plant - Threatened & Endangered Species of Alabama. R. Johnson & B. Wehrle; www.pfmt.org.
Shripmer: NOAA Photo Library. | |
• Overview
• Alabama
• Florida
• Louisiana
• Mississippi
• Texas
• Overview
• Apalachicola Bay
• Big Thicket
• Everglades
• Laguna Madre
• Mississippi Delta
|
|
|
|
| | | | |
© Union of Concerned Scientists
Page Last Revised: 06/24/08 |
|
|
