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Bottomland Forested Wetlands
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FYI
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Forested wetland systems support fish and wildlife populations that are an integral
part of the state's $4.2 billion hunting and fishing industry.
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Bottomland hardwood systems are the most diverse Texas ecosystems; they are also
ranked as one of the most endangered ecosystems in the United States. Bottomland wetlands are plant communities that have been created as a result of the actions of
creeks, rivers, and floodplains. The bottomland hardwood forest is a part of a system that starts at a river's headwaters and ends in an estuary at the ocean. Trees found in
the bottomland hardwood forests include bald cypress, pecan, oaks, elm, cottonwood, and hackberry. These hardwoods, particularly old-growth hardwoods (50 to 100 years
old), contribute to the biodiversity of the wetland system. They also provide food and shelter for wildlife. The bottomland hardwood forests are also referred to as riparian forests.
At least 189 species of trees and shrubs, 42 woody vines, 75 grasses, and 802 herbaceous plants occur in Texas
bottomlands. Bottomland systems also support 116 species of fish, 31 species of amphibians, 54 species of reptiles, 273 species of birds, and 45 species of mammals.* Seventy-four species of threatened and endangered animals
depend directly on bottomland hardwood systems. Over 50 percent of all the neotropical songbirds that are not listed
as endangered or threatened live, nest, or migrate through bottomland hardwood forests. Thirty-one water bird
species (mallards and wood ducks), 11 species of fur bearers, and the eastern wild turkey, swamp rabbit, and gray squirrel all depend on bottomland hardwoods.*
These bottomland systems, apart from their habitat functions, play a vital role in maintaining water quality. By serving
as depositories for sediments, wastes, and pollutants from runoff, bottomland forests enhance the water quality of the
bays and estuaries that lie at the lower end of these riparian corridors. Some pollutants are transformed into less-harmful substances by microbiological agents in the floodplain.* Bottomlands also help contain floodwaters when
rivers overflow.In the eighteenth century, the area we now call Texas had approximately 16 million acres of
hardwood-bottomland riparian corridors. Today, the state has 5.9 million acres of bottomland hardwoods and other
other forested riprarian vegetation and 95,000 acres of swamps. Since pre-settlement days, there has been a 63
percent loss of the original bottomland hardwoods.This acreage currently comprises three percent of the total land area of the state.* The majority of bottomland hardwood acres are found in East Texas; only about one million acres
are scattered throughout the western portion of the state.
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FYI
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In 1997, eighty-one percent of the hardwood removed in Texas was used to
manufacture wood products.
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Reservoirs, development, and the conversion of forests to agricultural land have been
most responsible for the destruction of bottomland hardwood systems in Texas. A 1994 Texas Parks and Wildlife Study showed that losses of bottomland hardwoods have
continued in Texas at the rate of about 12 percent per decade.* There is some
indication that this trend is being reversed due to efforts by private landowners to convert agricultural land to forestland, efforts by the Texas Parks and Wildlife
Department to reestablish hardwoods on state -owned land and activities funded by the Farm Bill's Wetland Reserve Program to replant hardwoods on private lands. Existing
bottomland hardwoods though are still threatened by proposed water reservoirs, land conversion, and consumption of
wood products. The proposed Marvin Nichols Reservoir in Red River County in Northeast Texas is expected to destroy 25,000 acres of hardwoods.
Texas bottomland hardwood habitat are a high priority for Texas Parks and Wildlife's conservation efforts.*
Playa Lakes
Texas playa lakes—shallow, circular basins—are the wintering wetland habitat for millions of waterfowl that migrate
from as far north as Canada. There are approximately 19,000 playa lakes located in 37 counties of the Texas High
Plains. The total area of playa basins has been estimated at 341,000 acres. Fifteen million birds annually migrate
through these playas in the fall and spring on their way to and from wintering habitat on the Gulf Coast and farther south.* Ducks, geese, and sandhill cranes also use these playas as stop-overs. The majority of these oases of wildlife
habitat are located within cultivated, privately held farmland. Precipitation and irrigation runoff contribute to the
development of these wetlands. But land-use practices, such as filling-in wetlands in order to increase cropland as well
as irrigation methods that limit runoff, are reducing the capacity of playas to provide food and water for waterfowl.
(Though not officially considered playas, feedlots in the Panhandle also are used as way stations for migrating birds.)
Coastal Wetlands
Coastal wetlands include marshes (fresh,brackish,and salt marshes) and coastal potholes. U.S. Fish and Wildlife
estimated that Texas had 937,000 acres of coastal marshes in 1956. Texas Parks and Wildlife estimates that between
the mid-1950s to 1989, there has been a net loss of 8 percent in estuarine marshlands, though they note that there
have been simulataneous losses and gains throughout the bay system during this time. During this 30 year period,
there was also a 54 percent loss of of freshwater marshes caused by the draining of wetlands to make room for urban development, and cropland and pastureland.* Texas Parks and Wildlife estimates there are 89,000 acres of potholes
or 18,401 individual potholes. These coastal wetlands provide habitat fora variety of marine organisms and hundreds of species of wildlife.
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