Estuary Issues

/Estuary Issues
Estuary Issues 2017-08-01T21:13:51+00:00

Management Conference members have identified seven priority problems in the estuary that are contributing to land loss, habitat modification, the decline in certain animal populations, water quality issues related to fish, shellfish, and humans, and contamination of sediment in the marshes.

Each of the priority problems, in some way, affect the next, making the resolution of each of the problems that much more pressing and complex. The action plans that are located in the CCMP work to directly address these problems, as well as the numerous institutional and societal factors that contribute to them.

In general, the overall health of the Barataria and Terrebonne basins show signs of years of abuse and neglect. The following seven problems must be overcome to prevent further degradation of the habitats, ecosystems, and cultural heritage that are so unique to the system.

The 7 Priority Problems include:

Hydrologic modification is considered a “linchpin” problem of the basins, indicating that all other problems revolve around, and are often affected by it. When we build levees, dredge canals, or cut through natural ridges, the natural flow of water is changed. In some cases, such changes accelerate erosion. In other cases, it can result in changed salinity of water bodies. As a result, fresh marsh can be changed to a more “salt tolerant” type. In more extreme cases, marsh can be converted to open water.

Levee

Levee

Straight Oil Field Canals

Straight Oil Field Canals


Louisiana marshes need a source of sediment to survive. Historically, the Mississippi River provided the sediment. Now, however, levees confine the sediment to the river thus bypassing the marshes, ultimately depositing it on the continental shelf in the Gulf. Our coastal marshes constantly undergo a natural process called “subsidence” which results in the land slowly sinking. In the past, the rate of sediment building equaled or surpassed the rate of sinking and the level of the marsh remained about the level of the sea.

Mississippi River Tributaries

Mississippi River Tributaries (Source)

Mississippi River Tributaries

Mississippi River Tributaries


What is known about the rate of habitat conversion, and ultimately land loss in the coastal areas of the Barataria and Terrebonne basins, is that it is alarmingly high. According to USGS study done in 2010, the BTES has lost a total of 865.57 square miles since 1935. https://pubs.usgs.gov/sim/3164/downloads/SIM3164_Pamphlet.pdf.

Coastal Louisiana Land Area

Coastal Louisiana Land Area


Living Resources are considered animals that live in the estuary. Living resources use the diverse habitats of the estuary. Approximately 735 species of birds, finfish, shellfish, reptiles, amphibians, and mammals spend all or part of their life cycle in the estuary. Several of the species are categorized either as threatened or endangered. Many factors contribute to declines in animal populations.

Blue Crabs

Gulf Shrimp


When too many nutrients, such as phosphorus and nitrogen, are in the water, a condition known as eutrophication occurs. The process begins with an accelerated growth of algae with the result being that oxygen in the water is depleted as plant matter decays, killing fish and shellfish.

Eutrophication

Eutrophication


Pathogens are disease-producing organisms such as bacteria and viruses. The sources of these organisms are human waste, pasture runoff from animal waste, and waste products of marsh animals such as nutria and birds. Examples are described below. Bacteria commonly found in sewage pollution can be of serious concern as it causes infection, rashes, and other serious diseases.Vibrio bacteria can cause both food borne and wound related illnesses.

Louisiana Beach Monitoring Program

Louisiana Beach Monitoring Program
(More Info)

Louisiana Beach Monitoring Program

Louisiana Beach Monitoring Program (Source)


Water, animal tissue, and sediment testing have identified a variety of toxic substances in the basins. Some of the substances are known cancer-causing agents while others affect reproduction. When some animals consume contaminated food, the toxic concentration is magnified. Human consumption of highly contaminated seafood poses health risks. Toxics found throughout the system come from point sources, such as industry, and non-point sources, such as urban runoff.

Toxic Substance Transition Pyramid

Toxic Substance Transition Pyramid
(Source)


Hydrologic modification is considered a “linchpin” problem of the basins, indicating that all other problems revolve around, and are often affected by it. When we build levees, dredge canals, or cut through natural ridges, the natural flow of water is changed. In some cases, such changes accelerate erosion. In other cases, it can result in changed salinity of water bodies. As a result, fresh marsh can be changed to a more “salt tolerant” type. In more extreme cases, marsh can be converted to open water.

Levee

Levee

Straight Oil Field Canals

Straight Oil Field Canals


Louisiana marshes need a source of sediment to survive. Historically, the Mississippi River provided the sediment. Now, however, levees confine the sediment to the river thus bypassing the marshes, ultimately depositing it on the continental shelf in the Gulf. Our coastal marshes constantly undergo a natural process called “subsidence” which results in the land slowly sinking. In the past, the rate of sediment building equaled or surpassed the rate of sinking and the level of the marsh remained about the level of the sea.

Mississippi River Tributaries

Mississippi River Tributaries

Mississippi River Tributaries

Mississippi River Tributaries
http://www.mvn.usace.army.mil/Missions/Mississippi-River-Flood-Control/Mississippi-River-Tributaries/


What is known about the rate of habitat conversion, and ultimately land loss in the coastal areas of the Barataria and Terrebonne basins, is that it is alarmingly high. According to USGS study done in 2010, the BTES has lost a total of 865.57 square miles since 1935. (Source.)

Coastal Louisiana Land Area

Coastal Louisiana Land Area


Living Resources are considered animals that live in the estuary. Living resources use the diverse habitats of the estuary. Approximately 735 species of birds, finfish, shellfish, reptiles, amphibians, and mammals spend all or part of their life cycle in the estuary. Several of the species are categorized either as threatened or endangered. Many factors contribute to declines in animal populations.

Blue Crabs

Gulf Shrimp


When too many nutrients, such as phosphorus and nitrogen, are in the water, a condition known as eutrophication occurs. The process begins with an accelerated growth of algae with the result being that oxygen in the water is depleted as plant matter decays, killing fish and shellfish.

Eutrophication

Eutrophication


Pathogens are disease-producing organisms such as bacteria and viruses. The sources of these organisms are human waste, pasture runoff from animal waste, and waste products of marsh animals such as nutria and birds. Examples are described below. Bacteria commonly found in sewage pollution can be of serious concern as it causes infection, rashes, and other serious diseases.Vibrio bacteria can cause both food borne and wound related illnesses.

Louisiana Beach Monitoring Program

Louisiana Beach Monitoring Program
(More Info)

Louisiana Beach Monitoring Program

Louisiana Beach Monitoring Program (Source)


Water, animal tissue, and sediment testing have identified a variety of toxic substances in the basins. Some of the substances are known cancer-causing agents while others affect reproduction. When some animals consume contaminated food, the toxic concentration is magnified. Human consumption of highly contaminated seafood poses health risks. Toxics found throughout the system come from point sources, such as industry, and non-point sources, such as urban runoff.

Toxic Substance Transition Pyramid

Toxic Substance Transition Pyramid
(Source)