Factoids about Louisiana's Coastal Wetlands

Some figures may be out of date

Benefits of the Breaux Act

(Coastal Wetlands Planning, Protection and Restoration Act)

to Louisiana and the Nation

The Breaux Act:

Gives national recognition to a problem of national scope--the yearly loss of 25 to 35 square miles of the nation's coastal wetlands, or one acre every 25 minutes. Louisiana contains 40 percent of the nation's coastal wetlands, and 80 percent of the loss of coastal wetlands.

Approved projects are estimated to prevent 20 percent of the projected future loss of Louisiana's coastal wetlands through the next 20 years.

Provides Federal assistance for a problem exacerbated by activities which benefit residents far outside the coastal zone; extraction of oil and gas (15 percent and 20 percent, respectively, of the nation's supplies are extracted from Louisiana's coastal wetlands); Federal navigation projects on the Mississippi River, which carries about 25 percent of the country's exported commodities and 24 percent of grain shipments (tonnage moving through the lower river between Baton Rouge and the Gulf is valued in excess of $30 billion annually); and the Mississippi River and Tributaries project, which controls flooding on the lower Mississippi and is estimated to have prevented over $35 billion in damages. All of these activities have played a role in advancing the loss of Louisiana's coastal wetlands.

Helps preserve a wetland-dependent fishery of national significance (an average of nearly 20 percent of the nation's commercial harvest from 1983-1995).

Can help in preserving diverse cultural and historical resources located in the state's coastal wetlands (for example, the Cajun and Indian cultures).

Has created a new network of wetlands restoration experts from Federal and state agencies, local governments, academia, and the private sector.

Brings together various interests (landowners, commercial and recreational fishermen, oil and gas interests, navigation interests, environmental interests, etc.) under a single program.

LAND LOSS

Louisiana contains 40% of the nation's coastal marshes (C.E. Alexander and M.A. Broutman. 1986. an Inventory of Coastal Wetlands of the USA, NOAA, Washington DC.). According to a long-term Corps of Engineers data base, Louisiana is currently losing 25 square miles of land per year. As can be seen below, the rate has decreased recently from the high rate in the 1960's and early 1970's.

1932-1956 15 square miles per year

1956-1978 41 square miles per year

1978-1983 31 square miles per year

1983-1990 25 square miles per year

These figures were arrived at by COE researchers comparing aerial photographs from the varying time periods and determining the amount of land that became water (J. B. Dunbar, L.D. Britsch and E.B. Kemp III, 1992. Land Loss Rates, Louisiana Coastal Plain, Report 3. Technical Report GL-90-2).

According to a 1956-1990 database developed by the U.S. Geological Surveys' National Wetlands Research Center, coastal wetland loss for Louisiana represents 67% of the nation's total loss. For the time period 1978-90, the loss was 290,432 acres, representing an annual loss rate of 24,203 acres per year for this 12-year period; that is equal to 37.8 square miles per year. For the time period 1956-78, net wetland loss was even greater, 661,700 acres, representing a loss rate of 30,000 acres per year; that is equal to 47 square miles per year. J.B. Johnston, M.C. Watzin, J.A. Barras, and L.R. Handley. 1995. Gulf of Mexico Coastal Wetlands: Case Studies of Loss Trends. Pages 269-277 in E.T. LaRoe, G.S. Farris, C.E. Puckett, P.D. Doran, and M.J. Mac, eds. Our living resources: a report ot the nation on the distribution, abundance, and health, of U.S. plants, animals, and ecosystems. U.S. Department of the Interior, National Biological Service, Washington, D.C.

Louisiana's Coastal Wetlands Overview
Commercial Value
Recreational Value
Wildlife Habitat
Water Quality
Storm Buffer
Erosion Control
Flood Control
Education and Scientific Research

FACTOIDS ABOUT

Louisiana's Coastal Wetlands Overview

BASELINE 1956

Wetlands 3.8 million acres
Water 4.6 million acres
Uplands 0.7 million acres

BASELINE 1990

Wetlands 2.95 million acres
Water 5.43 million acres
Uplands 0.7 million acres

LOSS TRENDS OF VEGETATED WETLANDS (LAND LOSS)

38 square miles per year lost -- 1956 to 1990
35 square miles per year lost -- 1978 to 1990
Total of 1,330 square miles lost (851,200 acres) between 1956 and 1990

FUTURE LOSSES

Assume a 50 year horizon from 1991 to 2040
Difficult to estimate due to possible effectiveness of CWPPRA -- assume no projects
Assume loss rate stays constant at 35 square miles per year = 1,750 square miles lost (1,112,000 acres) between 1991 and 2040
Assume stepped five-year changes in rate of 5 square miles per year, decreasing losses down to 15 square miles per year until year 2040 = 1,000 square miles lost (640,000 acres) between 1991 and 2040
Assume stepped five-year changes in rate of 5 square miles per year, decreasing losses until year 2025 where no net loss is achieved = 700 square miles lost (448,000 acres) between 1991 and 2025
Summary: in next 50 years (1991 to 2040) total wetland losses could range from 700 to 1750 square miles (448,000 to 1,112,000 acres)

FEDERAL LANDS

Coastal Louisiana has 9 National Wildlife Refuges covering 277,000 acres
Jean Lafitte National Historical Park has 11,000 acres of coastal wetlands

CHARACTERISTICS

Louisiana has 40% of the nation's coastal wetlands
Louisiana also has 60 to 80% of the total loss of coastal wetlands in the U.S.
Loss rate prior to 1956 was estimated at 15 square miles per year
Vegetated marsh was lost at a rate of 35 to 39 square miles per year from 1956 to 1990
Pre-historic and historic gains in marsh largely due to inflows of fresh water and sediments
Riverine processes dominated and overwhelmed subsidence and marine processes in area of river influence
Human intervention in the riverine processes allowed subsidence and marine processes to dominate in historical river systems over the past 40 years
Human activities/construction in the coast accelerated marine and global processes (erosion, salt water intrusion into fresh systems, sea level rise)
Largest cause of wetland loss is the management of the lower Mississippi River within a fixed course by levees that prevent enrichment and building of marsh from fresh water and sediments
Other activities that caused or exacerbated the loss include: canals and waterways built for pipelines, oil and gas development (including OCS development), transportation; shoreline erosion from ship traffic; failed land reclamation; building drainage channels; and human residential and commercial development
There is general scientific agreement that the huge vegetated marsh of coastal Louisiana is directly responsible for the large annual production of seafood, and use by wildlife and fish.
Fishery scientists (NMFS) attribute recent declines in fishery production to marsh loss

FACTOIDS ABOUT

COMMERCIAL VALUES

Fisheries

1990 U.S. fisheries landings had a dockside value of $3.6 billion
Total 1990 consumer expenditures exceeded $26 billion
70% of the commercial fisheries value comes from coastal species: shrimp, blue crabs, oysters, menhaden
Louisiana contributes nearly _ of the nation's commercial catch
Louisiana historically leads the nation in harvests of shrimp, menhaden, crabs and oysters
Biomass of Louisiana fishery landings ranks second to Alaska
Louisiana fishery landings is third in economic value
Louisiana coastal fisheries landings had a dockside value of $300 million
Value of Louisiana commercial fisheries was $680 million in 1991

Forestry

82 million acres in U.S. classified as forested wetlands
Value of southern forested wetlands exceeds $10 billion annually
Large bottomland hardwood and cypress-tupelo swamps remain in coastal Louisiana

Furbearers

More than 40% of the nation's wild fur harvest comes from Louisiana wetlands

Alligators

More than 25,000 wild alligators are harvested each year in Louisiana
Over 100 commercial alligator farms are in south Louisiana
Value of hides/meat from both wild and farm harvests exceeds $16 million annually

Farming and Ranching

Crop production in jurisdictional and prior converted wetlands is important to economy
Cattle production in coastal areas exceeds $25 million per year

Oil and Natural Gas

Louisiana oil and gas production is very important to the state and nation
Between 1917 and 1940, 60 oil fields were discovered in coastal Louisiana (1291 wells drilled)
By 1994 there were 523 oil fields and 23,477 wells in coastal Louisiana
Oil and gas related severance taxes exceed $500 million
Approximately 150 million barrels of oil and 130 million cubic feet of gas produced
Most of Louisiana production is from coastal wetland areas
Oil/Gas infrastructure handling over 60% of U.S. imports is located in south Louisiana
OCS wells in the Gulf of Mexico account for 95% of U.S. OCS produced oil
OCS wells in the Gulf account for 99% of OCS produced gas in the U.S.
There are 30,970 wells on the OCS (1994)
From the OCS there are 160 major pipeline corridors to the Louisiana coast
There are 21,232 miles of OCS pipelines in the Gulf
There were 13,384 jobs in oil and gas companies working in the OCS (1992) and 81% were residents of Louisiana (10,841)
Payroll for Louisiana residents working on the OCS was $593 million
Gulf of Mexico OCS oil and gas production revenues are the third largest contributor to the U.S. treasury (behind IRS and Tobacco and Firearms Bureau)

FACTOIDS ABOUT

RECREATIONAL VALUES

Sport Fishing

Almost 900,000 licenses sold annually in Louisiana
Sport fishermen's expenditures total $13 billion annually

Sport Hunting

More than 330,000 hunting licenses issued in Louisiana (1991)
More than $430 million in expenditures for Louisiana waterfowl hunters (1991)

Eco-tourism

Boating, skiing, swimming, hiking, bird watching, photography and painting
More than 1.4 million people participated in non-consumptive fish and wildlife activities
Total expenditures in 1991 for Louisiana exceeded $220 million

Cultural Values

People who inhabit the coastal marshes, swamps and bayous of Louisiana are known worldwide for lifestyle, good food, and culture
This culture has strong, direct ties to coastal wetlands

FACTOIDS ABOUT

WILDLIFE HABITAT

Threatened and Endangered Species

79 species of animals and plants listed as T/E occur in wetlands in U.S.
11 T/E species occur in coastal Louisiana
Most of the 100 active bald eagle nests in Louisiana are on the coast

Migratory Waterfowl

15 million waterbirds use Louisiana's coastal wetlands and shorelines each year
4 to 6 million ducks winter in Louisiana (20% of continental population)
Over 400,000 geese overwinter in Louisiana

Migratory Neotropical Birds

Radar tracking shows 80,000 birds per mile of migration front arrive daily in Louisiana
In peak spring migration, 24 million birds per day arrive on the Louisiana coast

Resident Birds

Hundreds of thousands of colonial waterbirds reside in south Louisiana wetlands in over 100 colonies

Diverse Animal Populations

Like many estuarine systems, coastal Louisiana has a very diverse and productive invertebrate population
Numerous species of mammals, fish, reptiles and amphibians call this area home

Aquatic Productivity

Wildlife and fish productivity closely linked to detrital cycle of coastal wetlands
Wetlands are two to three times more productive than the most fertile agricultural lands
Abundant wetland vegetation productivity provides habitat and food to aquatic systems

Species Biodiversity

Wetland systems are among the most diverse in the world
Wetlands in coastal Louisiana are particularly diverse and productive

FACTOIDS ABOUT

WATER QUALITY

Non-point Source Pollution

Wetlands filter non-point sources, reducing nitrogen and phosphorus

Nutrient and Sediment Reduction

Wetlands filter and trap sediments as water flows from land to water

Chemical Pollution Reduction

Wetlands are very effective at removing some pesticides and heavy metals from water

Groundwater Recharge and Discharge

Wetlands play an important role in recharge of local and regional aquifers

FACTOIDS ABOUT

STORM BUFFER

Hurricanes and Tropical Storms

Coastal wetlands act as a buffer between the Gulf of Mexico and inhabitated inland areas
An estimated 60-75% of Louisiana's residents live within 50 miles of the coast (1993)
Between 1899 and 1995 over a dozen major hurricanes (class 3-5) hit Louisiana
Many coastal communities were abandoned following hurricanes in deteriorating coastlines and marshes (Cheniere au Tigre, Manilla Village, Balize, Cheniere au Caminada and St. Malo)
Hurricane Betsy flooded or destroyed 27,000 homes in coastal Louisiana in 1965
Hurricane Audrey killed 556 people in southwestern Louisiana in 1957
Hurricane winds subside substantially once they reach the wetland buffer
Coastal wetlands buffer the tidal increase and wave intensity of hurricanes
At risk are millions of people and billions of dollars in infrastructure (e.g. New Orleans)

Winter Storms

Wetlands also buffer the intensity and damages caused by winter storms

Winter storms tend to be less powerful but last longer, hence large damages

FACTOIDS ABOUT

EROSION CONTROL

Vegetated Wetlands

Help hold together areas prone to serious erosion
Areas of wetlands converted to other uses generally have high soil erosion
Shoreline erosion rates in coastal Louisiana exceed 100 feet per year in some areas

FACTOIDS ABOUT

FLOOD CONTROL

Damages

More than $93 million in damages caused by flooding within the Tensas Basin
In 1993 southern Louisiana had flood related damages of more than $10 million

Natural Flood Control

Wetlands provide natural flood control by detaining and slowing flood waters
Maintaining wetland areas near developed areas may be the least expensive flood control

FACTOIDS ABOUT

EDUCATION AND SCIENTIFIC RESEARCH

Functions and Values

Understanding the full range of functions and values
Landscape functions
Values for commercial and sport activities
Functions as habitat for fish and wildlife
Production, productivity, biodiversity and dynamics of wetlands
Ecological relationships

Characteristics and Structure

Vegetation of wetlands
Invertebrate communities
Hydrology of wetlands
Soils of wetlands
Vertebrates of wetlands
Detrital cycle
Water quality

Classification and Inventory

Kinds of wetlands and wetland systems
Methods to inventory wetlands structure
Methods to catalog wetland functions and values

Status and Trends

How wetland communities change
Human development of wetland areas -- what is lost or gained
How many acres and numbers of wetlands lost by area and time frame