Chapter 7 – State of the Bay, Third Edition

CHAPTER 7 – STATE OF THE BAY, THIRD EDITION

Key Habitats of the Galveston Bay Watershed

Written & Revised by L. James Lester

The Gulf coastal plain rises gently from sea level to around 200 feet … Much of the flora is in tall grass and midgrass prairies and cordgrass marshes … The coastal marsh itself is a narrow belt of low wetlands. The fauna is very diverse, with more than three hundred species of birds relying on this area for food and rest on their spring and fall migrations ... Spanish records tell us that there were extensive open prairies of little bluestem, Indian grass, and sedges on the uplands between the many rivers. The bottomland hardwoods were abundant, with sugarberry, pecans, elm, and live oak. Now, most of the land has been plowed and cut into farms and ranches.

—Richard Bartlett, in Saving the Best of Texas (1995)

Introduction The Galveston Bay system contains a variety of habitat types, ranging from open water areas to wetlands to upland prairie. Regional habitats support numerous plant, fish, and wildlife species and contribute to the tremendous biodiversity found in the watershed. The maintenance of varied, abundant, and appropriate habitat is a requirement for the preservation of the characteristic biodiversity of the Galveston Bay system.

Habitat is defined as the ecological or environmental area where organisms live. This chapter provides details on the most State of the Bay 2009 Bay the of State vulnerable habitats found – in and around Galveston Bay; including their location, relative area, CHAPTER 1 biological characteristics, State of the Bay

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the ecological services 7 they provide and specific Figure 7.1. Map of habitats and developed lands in the Lower Galveston threats to their Bay watershed. Data source Coastal Change Analysis Program land use- land cover data (NOAA 2006).

CHAPTER existence. Terrestrial

and aquatic habitats that are common in the Lower Galveston Bay watershed (see Figure 7.1) will be considered, including coastal prairie, riparian forest, wetland, oyster reef, and seagrass meadow. Three of the bay’s aquatic habitats are emphasized because they have been identified in The Galveston Bay Plan (GBNEP 1994) for special conservation and restoration efforts. First, wetlands serve important hydrological and ecological functions in the bay ecosystem, but have experienced significant rates of loss over the past century (White et al. 1993). Second, seagrass meadows are a valuable but now rare habitat in the Galveston Bay system outside the Christmas Bay Complex (Pulich and White 1991; Pulich 1996; Williams 2007). Third, oyster reefs are important as indicators of the overall condition of the ecosystem and are the basis for an important commercial fishery. Oyster-shell reefs were dredged and exploited, with attendant ecological detriment, for many decades (see Chapter 3). Recently, oyster reefs bore the brunt of storm surge effects from Hurricane Ike. Two terrestrial habitats: coastal prairie and riparian forest (including their associated freshwater wetlands), are of special conservation concern in the Lower Galveston Bay watershed. Alteration of these habitats for urban and suburban development has left little of their original area, especially in the case of coastal prairie.

Wetlands Wetlands are “lands transitional between terrestrial and aquatic systems where the water table is usually at or near the surface or the land is covered by shallow water” (Cowardin et al. 1979). Wetlands in the Lower Galveston Bay watershed play several key ecological roles in protecting and maintaining the health and productivity of the estuary. In this chapter we will focus on 2 types of wetlands: (1) Fringing marshes are estuarine. They are situated along the edge of Galveston Bay and are intermediate between the aquatic habitats of the bay and the terrestrial habitats that surround it. (2) Freshwater wetlands are palustrine. They lie inland from the bay and may be

embedded in coastal prairie, riparian corridors, or forest habitat complexes. State of the Bay

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CHAPTER 2

The Origin and Importance of Wetlands Wetlands were formed in Galveston Bay by the long-term interaction of the ecosystem's physical processes (see Chapter 5). These processes occurred throughout geologic time and most still occur today. Rainfall and surface runoff, water table fluctuations, streamflow, evapotranspiration, waves and longshore currents, lunar and wind-driven tides, storms and hurricanes, deposition and erosion, subsidence, faulting, and sea level rise form an array of physical environments that range from being infrequently to permanently inundated with water (White and Paine 1992). The resulting elevations of these habitats range from submerged bay bottom, through the intertidal zone, to the zone above high tide that is infrequently flooded by storms. The continuing action of physical processes and the proximity to saltwater and freshwater sources determine the location and composition of wetland plant communities. In addition to being formed by physical processes, wetlands are important elements of many biological processes that support the bay ecosystem. Hydrologically, fringing marsh and freshwater wetlands are valuable filtering zones for polluted runoff, protecting the bay from excessive organic and sediment loadings from the land. Freshwater wetlands also serve as flood control areas that release rainfall runoff slowly compared to the rapid discharge from man-made drainage systems. Finally, well-established, vegetated wetlands also form a buffer between high-energy water and land, preventing or reducing shoreline erosion. Following the disaster of Hurricane Katrina in 2005, there was general recognition that the diminution of wetland extent seaward from New Orleans permitted the storm surge to reach the city at a greater height than if it had moved over intact wetlands (Day et al. 2007). Wetlands are among the most productive biological systems on the planet (Day et al. 1989; Keddy 2000). They may be more important to the Galveston Bay system than to many other bays (Sheridan et al. 1989). Among the most important of wetland functions is their role in providing habitat for many species of plants, fish, birds, and other wildlife. All of Galveston Bay’s principal commercial and recreational fishery species rely on estuarine wetlands during at least some part of their life cycle. The wetland edge is a particularly important habitat for white and brown shrimp (Whaley and Minello 2002). Other marsh-dwelling species

include blue crab, red drum, spotted seatrout, Southern flounder, and Gulf menhaden. In the same way, wetlands are important nurseries to hundreds of non-commercial species that comprise a large part of the bay food web. Bird species, such as snowy egrets, great egrets, reddish egrets (Figure 7.2), roseate spoonbills, tri-colored herons, black-crowned night herons and great blue herons use marsh as feeding habitat. State of the Bay 2009 Bay the of State

– Types of Wetlands The distribution of fringing and freshwater wetlands occurs along a generally south-to-north salinity gradient. Fringing marsh (estuarine wetlands) typically occurs in the southern portions of the bay near the Gulf passes, while freshwater wetlands are found inland and at points farther north, along bayous and near CHAPTER 1

State of the Bay the mouths of rivers. The characteristics of these wetland classes are described below.

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7 CHAPTER

Estuarine Wetlands Estuarine wetlands exist in the Galveston Bay system across a salinity gradient and are classified into salt marshes and brackish marshes. Estuarine wetlands are often referred to as fringing marshes because they are found near the shoreline of the bay at the land-water interface.

Salt Marsh Salt marsh communities (Figure 7.3) are found in high-salinity areas along protected estuarine shorelines. Prevalent species in the salt marsh community include smooth cordgrass (Spartina alterniflora), saltwort (Batis maritima), saltgrass (Distichlis spicata) and glasswort (Salicornia spp.) (White and Paine 1992). Smooth cordgrass, which lives in the intertidal zone, dominates the low salt marsh community (e.g., the portion of the marsh that is most frequently inundated by bay waters). While living, cordgrass is seldom eaten, and then by only a few herbivores. Figure 7.3. Smooth cordgrass (Spartina alterniflora) Once dead it nourishes the large bay food salt marsh located near Bayou Vista. Image © 2007 web as detritus. iStockphoto.com Edges of the salt marsh serve as refuge and nursery for juveniles of many species, especially brown and white shrimp. These habitats are also important feeding grounds for wading birds, such as herons and egrets. At higher elevations, marsh hay (or saltmeadow cordgrass, Spartina patens) and Gulf cordgrass (S. spartinae) occur, although they are more common in brackish marshes (White and Paine 1992).

Brackish Marsh This community inhabits the transitional zone between salt marsh and fresh marsh and is affected by highly variable water levels and salinities. As would be expected, a number of species use this habitat, ranging from fresh water to salt-marsh species. In general, the brackish marsh is dominated by marsh hay and saltgrass. Other species include black needlerush (Juncus roemerianus), common reed (Phragmites australis) and State of the Bay

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big cordgrass (Spartina cynosuroides), seashore paspalum (Paspalum vaginatum), longtom (Paspalum lividum) in 7 fresher areas, and isolated clumps of saltmarsh bulrush (Bolboschoenus robustus) and Olney bulrush (Schoenoplectus americanus) (White and Paine 1992). CHAPTER

Freshwater Wetlands

Fresh Marsh Fresh marshes (Figure 7.4) are primarily found in areas where rainfall runoff accumulates (old meander scars of rivers and streams found in Harris, Fort Bend and Brazoria Counties), where rivers and streams provide a water source (oxbows and marshes associated with the fluvial morphology of existing rivers), and locations where fresh groundwater is exposed in a surface depression (interdunal swales on Galveston Island and the Bolivar Peninsula). Marshes associated with the Chenier Plain east of Galveston Bay proper show a gradual slope in elevation to the Gulf. These areas provide transitional areas from completely fresh to intermediate to brackish to saline marshes. The water in freshwater marshes is sufficient to maintain a low salinity suitable for such plants as sedges, rushes, and coastal arrowhead (Sagittaria lancifolia). In low, wet areas, the exotic and invasive water hyacinth (Eichhornia crassipes) can be found, while panic grasses (Rhynchospora spp.) and spiny aster (Chloracantha spinosa) can be found in higher areas. Many of the freshwater wetlands found in the Lower Galveston Bay watershed exist in complexes on the coastal prairie. The term pothole is used to describe these small, well-defined, freshwater wetland depressions (Figure 7.4). Prairie pothole complexes consist of potholes and pimple mounds 1–2 feet tall (sometimes called mima mounds). The hydrology of prairie pothole complexes can be very diverse with deeper potholes being saturated for up to 6 months at a time. Neighboring pimple mounds may be semiarid for most of the year (Moulton and Jacob 2000).

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Figure 7.4. Photo of a freshwater marsh in Grimes Prairie at Armand CHAPTER Bayou Nature Center. Image courtesy Andrew Sipocz.

Figure 7.5. Infrared satellite view of vegetation north and east of East bay: (left) before Hurricane Ike and (right) after Hurricane Ike (image taken September 28, 2009). Living vegetation is displayed in red; inundated areas, in blue-green. Image courtesy NASA-GSFC-METI- ERSDAC-JAROS, and U.S.-Japan ASTER Science Team.

Freshwater wetlands also exist on the Chenier Plain in the eastern portion of the Lower Galveston Bay watershed. Marsh habitats in this area are vulnerable to inundation by salt water during storms. Tropical

Storm Francis (1998) and Hurricane Ike (2008) both had storm surges that pushed saline water into freshwater marshes on the eastern side of Galveston Bay leading to the death of much of the standing biomass. The damage to the marshes is visible in satellite images as shown in Figure 7.5. It may take decades for these marshes to recover, and then only with sufficient precipitation to lower the salinity in the water State of the Bay and sediment. –

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Forested Wetlands Forested wetlands are found on the floodplains of rivers and streams that cross the Texas coastal plain. In the Galveston Bay system, this community is located almost exclusively in the Trinity River valley. Forested wetlands may occur as bottomland hardwood forests or swamps (Moulton and Jacob 2000) (Figure 7.6). The dominant plant species in the swamp community is bald cypress. The plant community also includes buttonbush (Cephalanthus occidentalis), water elm (Planera aquatica), and water hickory (Carya aquatic) (White and Paine 1992).

Trends in Wetland Distribution Understanding where wetlands are located and how their area has changed over time is critical if these State of the Bay 2009 Bay the of State important habitats are to be effectively protected and restored. Studies to classify and assess wetlands are a – priority nationally and in the Galveston Bay system. Numerous analyses to quantify wetland acreage have been performed to determine the change in areal coverage of wetland habitats in the Galveston Bay system (White et al. 1993; Pulich and Hinson 1996; White et al. 2004 ; Jacob and Lopez 2005; NOAA 2006; CHAPTER 1

State of the Bay Webb 2006; Gonzalez and Lester 2008). While the studies often use different methodologies or look at

– slightly different areas (Figure 7.7), all of the studies indicate some gains and numerous losses in the 7 different classes of wetlands over the years. CHAPTER

The factors influencing wetland distribution are complex, making it difficult to get an annual snapshot of wetland status. Land-cover mapping from aerial photography is difficult to compare because variation is introduced by differences in photographic methods, seasonal vegetation, weather, climate changes (e.g., the El Niño southern oscillation) and classification algorithms. It can be even more of a challenge to reconcile classifications made from aerial photographs with those from satellite images. Aerial photography can resolve features less than 2 meters in one dimension, whereas Landsat satellite images—often used for land- cover classification—have resolution of 30 meters. One advantage of satellite images is their frequency. Aerial photography of large areas usually occurs several years apart, while satellites orbit over an area with a period of days. Until recently, only one wetland classification program, the National Wetland Inventory (NWI), produced sequential estimates of wetlands in the Lower Galveston Bay watershed using a consistent methodology based on aerial photography and on the classification system of Cowardin et al. (1979). For the Estuary Program’s region, the last NWI was produced from aerial photography taken in 1992 and 1993. Over the last 10 years, the National Oceanic and Atmospheric Administration’s Coastal Change and Analysis Program (C-CAP) has produced 3 land-cover classifications of the Gulf Coast using a consistent methodology based on the Cowardin et al. (1979) system and Landsat satellite images collected at 5-year intervals. This permits more frequent assessment of trends in abundance and distribution of wetland types. There are 3 C-CAP land cover classifications from the years 1996, 2001 and 2005. However, 2001 was an unusually wet year in which Tropical Storm Allison delivered up to 37 inches of rain in June. A comparison of habitat amounts produced results showing a State of the Bay wetland acreage increase from 1996 to

Figure 7.7. Wetland studies are difficult to compare –

2001 for some classifications. When the because they often cover different geographic areas and 7 2001 classification was compared with may use different methods. Image courtesy Houston Advanced Research Center. that for 2005, the result was an apparent CHAPTER

rapid decrease in acreage of some types of wetlands. Therefore, the comparison of 1996 and 2005 appears to be a more accurate way of estimating trends. The overall error rate for the C-CAP land cover classification is estimated by NOAA at ± 15 percent.

Estuarine Wetlands

Historic Trends The area of estuarine marshes (Figure 7.3) in the Galveston Bay system has been estimated several times over the last 20 years using aerial photography and satellite image interpretation. An early land cover classification done for the Galveston Bay Estuary Program (White et al. 1993) estimated that 35,120 acres of emergent wetlands (estuarine and freshwater; does not include forested or scrub-shrub) disappeared from the Galveston Bay system (an area covering 30 quads; see Figure 7.7) over a 37 year period between 1953 and 1989. Of that total acreage, estuarine emergent marshes decreased in area by 9,480 acres, or 8 percent (Table 7.1). That averages to a loss of approximately 256 acres of estuarine marsh per year during the 1953–1989. White et al. (2004 ) found that estuarine marshes decreased by 3,833 acres between the 1950s and 2002 on Galveston and Follets Island and on Bolivar Peninsula.

Table 7.1. Acreage of estuarine and freshwater wetlands in 30 quads of the Lower Galveston Bay watershed from 1953 to 1989. Data source: (White et al. 1993)White et al. 1993.

Acres Total Annual Percent Change Change Change Wetland 1953 to 1953 to 1953 to Classification 1953 1979 1989 1989 1989 1989 Estuarine Emergent 117,640 105,880 108,160 –9,480 –256 –8% Freshwater Emergent 47,850 32,250 22,210 –25,640 –693 –54%

Freshwater Forested 2,040 5,580 5,650 +3,610 +98 +177% Freshwater Scrub- 3,430 2,300 2,570 –860 –23 –25% Shrub Total 170,960 146,010 138,590 –32,370 –875 –19%

State of the Bay 2009 Bay the of State Recent Trends – An analysis of the NOAA C-CAP data for the same quads studied by White et al. (1993) shows a net gain in estuarine emergent wetlands of 2,268 acres, or 2 percent, between 1996 and 2005 (Table 7.2). That averages to a gain of 228 acres per year. When the same data were analyzed for the 5 counties surrounding CHAPTER 1 Galveston Bay (Brazoria, Chambers, Galveston, Harris, and Liberty) 1,047 acres of losses due to State of the Bay

– development were offset by gains in wetland acreage yielding a net increase in estuarine emergent wetlands 7 acreage of only 199 acres between 1996 and 2005 (Table 7.3).

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Table 7.2. Acreage of estuarine and freshwater wetlands in 30 quads of the Lower Galveston Bay watershed from 1996 to 2005. Data Source: (NOAA 2006). Acres Total Annual Percent Change Change Change Wetland 1996 to 1996 to 1996 to Classification 1996 2005 2005 2005 2005 Estuarine Emergent 120,893 123,168 +2,275 +228 +2% Freshwater Emergent 89,924 88,525 –1,399 –140 –2% Freshwater Forested 51,413 49,278 –2,136 –214 –4% Freshwater Scrub-Shrub 26,767 24,725 –2,042 –204 –8% Total 288,997 285,696 –3,302 –330 –1%

As noted above, methodological differences in studies on land-cover classification make comparisons across such studies difficult. However, both the analysis by White et al. (1993) and our analysis of the NOAA C-CAP data show that (1) the loss of estuarine wetlands has slowed considerably since 1989 and (2) the net losses in estuarine emergent wetlands in the Lower Galveston Bay watershed are much less than losses of freshwater wetlands. The most likely explanations of the arrested decline of estuarine wetlands are the regulatory protection of estuarine wetlands under the Clean Water Act and numerous habitat-restoration efforts by regional partners.

Freshwater Wetlands

Historic Trends In the Lower Galveston Bay watershed, the majority of wetland losses during the last 50 years can be attributed to the loss of freshwater wetlands (White et al. 1993; Jacob and Lopez 2005; Gonzalez and Lester 2008). White et al. (1993) estimated that, of the 35,120 acres of emergent wetlands lost during 1950–89, 73 percent (25,640 acres) were freshwater wetlands (Table 7.1—a loss of nearly 641 acres per year. White et al. (2004 ) also found that freshwater wetlands decreased by 1,082 acres on Galveston and Follets Island and the Bolivar Peninsula between the 1950s and 2002. The acreage of forested wetlands increased by 177 percent (3,610 acres) between the 1953 and 1989 (Table 7.1). Almost all of this gain was due to (1) succession, the natural conversion of emergent and scrub-shrub habitats to forest, and (2) the invasion of Chinese tallow, an exotic species of tree with a high tolerance of saturated soil, rapid growth potential and low wildlife value.

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Recent Trends An analysis of the NOAA C-CAP data for the same quads studied by White et al. (1993) shows a net loss of 5,577 acres of freshwater wetlands between 1996 and 2005, or approximately 558 acres per year (Table 7.2). When the NOAA C-CAP data were analyzed for the 5 counties surrounding Galveston Bay (Brazoria, Chambers, Galveston, Harris, and Liberty), net losses of freshwater wetlands totaled 25,787 acres, or 1,826 acres per year. Of that amount, 15,823 acres of freshwater wetlands were lost to development. The other losses were due to the conversion of freshwater wetlands to non-wetland classifications. Some losses were due to changes in hydrology, which converted the wetland to upland vegetation suitable for grazing. Overall, 3 percent of wetlands were lost over the decade.

Table 7.3. Acreage of estuarine and freshwater wetlands in the 5 counties of the Lower Galveston

Bay watershed from 1996 to 2005. Data Sources: (NOAA 2006; Gonzalez and Lester 2008). Acres Total Annual Change Change Percent 1996 to 1996 to Change 1996 Wetland Classification 1996 2005 2005 2005 to 2005 Estuarine Emergent Wetland 163,029 163,228 +199 +20 0% Freshwater Emergent Wetland 169,746 168,068 –1,678 –168 –1% Freshwater Forested Wetland 564,715 546,451 –18,264 –1,826 –3% Freshwater Scrub-Shrub 75,061 69,016 –6,045 –605 –8%

Total 972,551 946,764 –25,787 –2,579 –3%

Work by Jacob and Lopez (2005) estimated that the Lower Galveston Bay watershed lost approximately 3 percent of its freshwater wetlands to development between 1992 and 2002 (9,052 acres of freshwater emergent, forested, and scrub-shrub classes). Most of the loss occurred in Harris County, which lost at least 13 percent of its freshwater emergent wetlands in the same period, with over half that loss occurring between 2000 and 2002. The spatial distribution of the losses in their study is shown in Figure 7.8. Even after considering the differences and limitations of the various methodologies, the estimates presented

State of the Bay 2009 Bay the of State here and by Jacob and Lopez (2005) document a continued and substantial loss of wetlands in the Lower

– Galveston Bay watershed. The estimates by Jacob and Lopez (2005) equate to a loss of 0.3 percent per year of classified freshwater wetlands in the Lower Galveston Bay watershed from 1992 to 2002. The NOAA C-CAP study estimates an annual rate of loss of 2,599 acres of freshwater wetlands, or 0.3 percent. CHAPTER 1 State of the Bay

The estimates are similar and confirm the chronic nature of wetland loss around Galveston Bay over the last –

7 50 years. Recent studies provide some hope that estuarine wetland loss appears to have been arrested. The challenge now is to arrest the loss of the freshwater classes of wetlands. CHAPTER

Figure 7.8. Freshwater Wetlands in the Lower Galveston Bay watershed in 2002. Areas in red were wetlands in 1992, but had been converted to developed land. Areas in green were classified as wetlands in 1992 and 2002. Data source: (Jacob State of the Bay and Lopez 2005). –

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The North Deer Island Protection Project: A Model for Habitat Conservation and Restoration Projects

By Lisa A. Gonzalez

Just west of the Galveston Causeway, along the Gulf Intracoastal Waterway between the Tiki Island development and Galveston Island, lay the Deer Islands. The 2 islands were named by early settlers who saw large numbers of deer using the islands to cross West Bay from the mainland to feed on Galveston Island grasslands (see Chapter 3). The smaller island is known as South Deer Island; the larger, North Deer Island.

Figure 7.9. North Deer Island. Image courtesy Jarrett Woodrow.

North Deer Island is one of Galveston Bay’s last natural islands and is recognized as one of the most important bird rookeries on the Upper Texas Coast. Houston Audubon (2009) estimates that 20,000 to 40,000 pairs of birds of 17 species nested on the island in 2005. The habitats found on North Deer Island include 25 acres of upland grasses and shrubs, and 119 acres of fringing wetlands, as well as mud and sand flats. The Texas Parks and Wildlife Department considers North Deer Island a Texas Gulf Ecological Management site (TPWD 2007). As with many of the other islands in Galveston Bay, North Deer Island has been affected by subsidence and wave-induced erosion. But it was the erosion caused by Tropical Storm Frances in 1998 that caught the State of the Bay

– attention of the Houston Audubon Society. The nonprofit organization, devoted to promoting the 7 conservation and appreciation of birds and wildlife habitat, set up monitors and discovered that the island was eroding at a rate of 5 feet per year (HAS 2009). CHAPTER

In response, the TPWD and the Estuary Program’s Natural Resource Uses Subcommittee mobilized many partners in an 8-year, $3.2 million effort to place over a mile of protective structures around the perimeter of the island and plant marsh grass to create additional wetland areas. The project was so large it was accomplished in 2 phases, with construction beginning in 2000 and the final work completed in 2008. The North Deer Island Protection Project is a prime example of what can be accomplished through partnership and stewardship of Galveston Bay’s natural resources; no fewer than 15 partner agencies and organizations made the project a reality: Audubon Texas, EcoNRG, the EPA Gulf of Mexico Program, the Houston Audubon Society and its members and friends, the Harris & Eliza Kempner Fund, the Meadows Foundation, Reliant Energy, the URS Corporation, the National Fish and Wildlife Foundation, the Shell Marine Habitat Program, the TCEQ, the TGLO, and the U.S. Fish and Wildlife Service. In 2008, the project’s partners were recognized by the EPA’s Gulf of Mexico Program with a first-place Gulf Guardian Award. In December 2009, project partners received the Coastal America Partnership Award, the only environmental award of its kind given by the President of the United States. Ecologically, the project’s success is evident on several fronts: it stopped the wave-induced erosion of the island and the constructed rock groins and earthen berm now trap sediment that can serve as substrate for marsh and mud flat habitats; the project preserved vital bird nesting habitat and created additional acres of fringing marsh; and all reports indicate that North Deer Island fared remarkably well in Hurricane Ike’s tremendous storm surge. The North Deer Island Protection Project stands as a model for other large habitat-conservation and restoration projects that will no doubt be needed as we continue to manage Galveston Bay for future generations.

North Deer Island is emblematic of natural habitats that are not only critical for fish and wildlife, but ultimately benefit the many people who live on and visit the Texas coast. This is only one of two natural islands left in West Galveston Bay. Without help, projections showed one-third of it would have eroded away in 30 years. —Carter Smith, Texas Parks and Wildlife Department, executive director (TPWD 2009)

The number of partners that stepped up to carry out this project is indicative of the island’s importance as a regional colonial waterbird rookery. The completion of this project will help to maintain colonial waterbird populations on the Upper Texas Coast for future generations to enjoy. State of the Bay

– —Jamie Schubert, Texas Parks and Wildlife Department, Upper Coast Ecosystem Assessment Team leader 7

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Causes of Wetland Loss The U.S. Fish and Wildlife Service reports that wetland losses at the national level between 1998 and 2004 were caused by urban development (39 percent), conversion to deepwater habitats (31 percent), rural development (22 percent), and silviculture (8 percent) (Dahl 2006). At a national scale, there have been wetland gains over the last 10 years from the conversion of agricultural and other land to wetlands. Wetlands have been declining in the Galveston Bay system since the 1990s at a rate of about 0.3 percent per year. Causes for wetland loss in this watershed include relative sea-level rise; land-use conversion for agricultural, urban, industrial, and transportation purposes; dredge-and-fill activities; and isolation projects (Moulton et al. 1997).

Relative Sea Level Rise Relative sea-level rise—the combination of land subsidence (due to subsurface fluid withdrawal) and rising ocean levels—has resulted in the drowning of numerous wetland areas throughout the bay system, and in creation of new wetlands by inundation of uplands. Overall, losses exceed gains. A total of 26,450 acres of 1950s freshwater and estuarine marsh were converted to open water or barren flats by 1989. Most of this conversion was due to subsidence caused by pumping of groundwater over the last 100 years. Pumping of petroleum may have an additional effect. Wetland areas affected by subsidence include the northern, western, and southern margins of Galveston Bay and the northeastern part of West Bay (White et al. 1993). In certain parts of the bay system, the effects of relative sea level rise were particularly severe. For example, more than 3,600 acres of marshland in the Virginia Point area around Jones Bay and Swan Lake were replaced by open

water and barren mudflat between the 1950s and 1989 (White et al. 1993) as a result of subsidence around Texas Figure 7.10. Homes in the Brownwood City. At the San Jacinto Battleground State Historic Site subdivision of Baytown were permanently along the Houston Ship Channel, subsidence has exceeded inundated by bay waters due to subsidence. Images courtesy Harris 9 feet since 1900 and several thousand acres of marsh were Galveston Subsidence District. replaced by open water until restoration began in 1998. State of the Bay

The Baytown area (Figure 7.10) offers another example of –

7 the effect of land-surface subsidence and the subsequent intrusion of open water into vegetated wetlands. The creation of the Harris-Galveston Subsidence District and regulation of groundwater withdrawal has dramatically slowed subsidence. Historical subsidence rates and the locations of groundwater wells are CHAPTER shown in Figure 7.11.

Wetland losses in some areas are partly offset by gains in others. Bay-wide subsidence and sea level rise are responsible for converting some previously upland areas to wetland areas. Conversions of uplands to wetlands are the result of water management programs implemented in national wildlife refuges and wetland-restoration and -conservation programs on agricultural lands (Dahl 2006). The conversion of uplands to wetlands generally took place in transitional areas peripheral to existing wetlands. Additional increases in emergent wetlands resulted after emergent vegetation spread over areas previously mapped as intertidal flats. This type of change was common in intertidal mud flats on the barrier islands (White et al. 1993). In the last 20 years, wetland restoration projects have used additions of substrate and breakwaters to protect and enlarge the areas covered by fringing wetlands. While losses of emergent marshes due to subsidence have slowed since the peak of groundwater withdrawal in the 1970s, the impact of global sea level rise on fringing marshes around the bay remains to be seen.

As sea level rises, estuarine wetlands will only be able to Figure 7.11. Subsidence in the Houston-Galveston Region, 1906– survive if they can grow 2000, and the current locations of groundwater wells. Data vertically at a rate equal to that sources: (HGSD 2008; TWDB 2008). of sea level rise, a process known as aggradation. To aggrade, wetlands require healthy plant growth and a steady supply of sediment to fill the water column created by sea-level rise. If the rate of aggradation is less State of the Bay than the rate of sea level rise, the wetlands must migrate inland to higher ground in order to survive. –

Wetlands situated in front of, or surrounded by, development or bulkheads will not be able to migrate to 7 higher ground as needed.

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Conversion of Land to Upland Uses Draining of wetlands, particularly freshwater wetlands, has caused significant wetland loss since the 1950s. White et al. (1993) estimated that 25,000 acres of emergent wetlands were converted to uplands between the 1950s and 1989. Much of the change during this period can be attributed to drainage ditches constructed to reduce flooding and increase the area available for livestock grazing (White et al. 1993). According to the C-CAP analysis, freshwater wetlands in the Lower Galveston Bay watershed declined by 25,787 acres from 1996 to 2005 (Table 7.3). About 6,000 acres now fall into the developed-land categories and about 7,000 acres are now cultivated or grassland. Conversion of natural lands to cropland and pastureland claimed 3,600 acres of freshwater wetlands in the 1950s to 1990s, mostly in the Hitchcock, Oyster Bayou and Chocolate Bay areas. Most of the conversion was to rice cultivation. Although some of these wetland conversions to uplands were related to natural conditions, such as annual (and seasonal) changes in moisture levels, most of the loss is probably due to direct conversion to upland range and cropland (White et al. 1993). Conversion of estuarine and freshwater wetlands to developed upland areas totaled about 5,700 acres when the Galveston Bay Estuary Program began in the early 1990’s. This was concentrated on the south and west sides of the bay, particularly around the Virginia Point area (White et al. 1993). The latest analysis of NOAA C-CAP data reports the conversion of around 1,000 acres of estuarine marsh to developed land between 1996 and 2005. This is much less than the conversion of approximately 15,800 acres of freshwater wetlands to developed land over the same time in the lower Galveston Bay watershed. Expansion of the Houston metropolitan area converts wetlands to human land uses, particularly in the outlying counties that have been primarily rural. Other upland conversion since the 1950s included conversion to oil and gas production, resulting in a net loss of more than 800 acres of wetlands. Much of the losses from oil and gas production were concentrated in the Virginia Point, Texas City, and High Island areas (White et al. 1993). This type of loss has greatly

decreased in recent years.

Dredge-and-Fill Impacts The relative impact of dredging and filling of wetlands is difficult to quantify due to the lack of a good baseline. There was little regulation of wetland conversion until the Clean Water Act of 1972. Given the anecdotal reports of European settlers (Weniger 1984), it is safe to assume that there were large seasonal

State of the Bay 2009 Bay the of State wetlands in the prairies of the Galveston Bay watershed that were drained or filled early in the development

– process. Section 10 of the Rivers and Harbors Act of 1899 charged the U.S. Army Corps of Engineers (USACE) to provide due regard to habitat conservation in planning federal water projects, but that law did not result in CHAPTER 1

State of the Bay the collection of data describing acres of wetlands converted to other uses. More than 70 years later, the

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7 implementation of Section 404 of the Clean Water Act of 1972 put in place a federal permitting system to protect wetlands and mitigate wetland losses. The permitting system, known collectively as Section 10/404 permitting, resulted in a record number of permit requests for wetland conversion and subsequent

CHAPTER agreements for wetland mitigation.

A quantitative assessment of regional wetland protection using data describing (1) permits to dredge and fill wetlands and (2) wetland mitigation is not readily available. Historic data describing the acreage of permitted dredge-and-fill activities and mitigation are not readily available in electronic format. Ward (1993) estimated the total loss of marsh due to dredging and filling by analyzing available records from federal dredging projects, available maps of the bay over time, and

USACE Section 404 Figure 7.12. Map showing Galveston Bay as it was in 1851. Note the dredge-and-fill connectivity between Turtle Bay (now Lake Anahuac) and Trinity Bay, permits since the and between Moses Lake and Dickinson Bay. Image courtesy National Archives. 1970s. Based on that information, Ward estimated that a total of 7,070 acres of marsh had been lost to dredging, filling, and disposal activities from 1900 to 1990. Of those losses, 2,920 acres were due to creation of designated disposal areas, 860 acres to navigation channels, and 3,290 acres to private dredging and filling under the USACE Section 404 permit State of the Bay

– program. The total area of wetlands lost to dredging and filling was up to 5 percent of the total wetland area and up to 20 percent of the net losses estimated for Galveston Bay (Ward 1993). 7 CHAPTER

Isolations Several large-scale modifications to the bay's shoreline resulted in large areas of open bay and marshland being isolated from the bay itself. The 1851 map shown in Figure 7.12 records a baseline for comparison with today’s shoreline position. Unfortunately, it does not record the type of vegetation in an area, so it will not help us estimate other types of wetland loss over the last 150 years. The most significant isolation and change of shoreline was the closure of Turtle Bay (now called Lake Anahuac) in 1936. Ward (1993) estimated that the closure of this area near the mouth of the Trinity River eliminated about 6,000 acres of shallow bay bottom and 10,000 acres of marshland from the estuarine system. Other estuarine marshlands that have been isolated from the bay (Ward 1993) include:

2,500 acres on the West side of Trinity 1,100 acres in the Trinity River delta Bay and the Trinity River delta for the for the Delhomme hunting area Reliant Energy Cedar Bayou cooling pond

2,000 acres on the North shore of 700 acres in the Moses Lake and East Bay isolated by numerous tidal Dollar Bay area for the Texas City gates (salt water barriers) flood control project

While these isolation projects did not result in a total conversion of these marshes to upland uses, they reduced the estuarine fringing marshland in the Galveston Bay system by 16,000 acres (Ward 1993).

Invasive Species

State of the Bay 2009 Bay the of State Exotic species are plants, animals, or microorganisms that come from other parts of the world. These

– species may be introduced unintentionally (accidental release) or intentionally (e.g., for a management purpose). Invasive species are exotics that are able to establish in a new region, form reproducing populations, and cause damage to ecological, economic, or social systems in the region in which they are

CHAPTER 1 introduced. State of the Bay

– Invasive species often lack the natural predators and diseases found in their native regions. Therefore, 7 populations of invasive species can thrive and may feed on, or successfully out-compete native species for resources. CHAPTER

Wetlands around the bay have been invaded by invasive plant species, including the Chinese tallow (Triadica sebifera), alligatorweed (Alternanthera philoxeroides), deep-rooted sedge (Cyperus entrerianus) and giant reed (Arundo donax). Nutria, a South American rodent, inhabits wetland habitats throughout the Lower Galveston Bay watershed, feeding on plant material. Brazilian peppertree (Schinus terebinthifolius) was found on Galveston Island and is the subject of a vigorous control effort (Figure 7.13). Identifying future invaders and taking effective measures to prevent their establishment constitutes an enormous challenge (Mack et al. 2000) . Efforts to identify general attributes of future invaders, predict their potential invasion ranges, and foresee the level of threat that

they present have Figure 7.13. Brazilian peppertree is now found on Galveston Island. Image courtesy Victor Madamba, Citizen Scientist with The Invaders of Texas often been Program, TexasInvasives.org. problematic.

Unless caught at an early stage of invasion, eradication is costly and the complete removal of an invasive species is rare. Two plant species in the Lower Galveston Bay watershed are evidence of this. Brazilian peppertree represents a species that was found early in its invasion. Control efforts have been confined to a relatively small area of the watershed, are cost effective, and have largely been successful. Chinese tallow is a species that is well-established in the Lower Galveston Bay watershed. It is estimated to be the most common tree in the Houston-Galveston region, comprising 23 percent of the region’s trees (Nowak et al. 2005). Eradication of Chinese tallow on a regional scale would be very costly and is likely beyond our collective ability. Successful control of invasive species in the Lower Galveston Bay watershed depends on the diligence and cooperation of residents as well as public and private entities. Prevention is the most cost effective and successful strategy for managing invasive species. This requires that we (1) think about the species that we State of the Bay

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intentionally bring into the Lower Galveston Bay watershed, (2) minimize the ways in which “hitchhikers” might accidentally be introduced to new habitats (such as by cleaning boating and mowing equipment), and 7 (3) employ a long-term, ecosystem-wide strategy rather than a species-by-species management approach. CHAPTER

Wetland Restoration and Preservation

Marsh Restoration and Creation The Galveston Bay Plan identifies the loss or degradation of aquatic habitats as the greatest priority problem in the Lower Galveston Bay watershed and sets a goal of increasing wetland area and restoring the quality of wetland habitats. Specifically, this goal calls for the creation or restoration of 5,000 acres of freshwater marsh and 8,600 acres of estuarine marsh. There have been many restoration projects focused on estuarine and riverine marshes. One reason is their location on or adjacent to public land. The largest sites have been on

submerged land belonging to the State or on Figure 7.14. Galveston Island State Park wetland dredge disposal sites belonging to the Port restoration terraces. Image courtesy Google Earth. of Houston Authority or USACE.

Techniques for restoring emergent marshes have evolved in recent years. Early restoration efforts involved the transplantation of propagules of smooth cordgrass (Spartina alterniflora) from a healthy marsh to locations where a similar

inundation regime was present. Different approaches are now used at individual restoration sites. These include: (1) using nurseries to grow plants (such as the wetland plant nursery at NRG’s EcoCenter), (2) moving sediments to create State of the Bay 2009 Bay the of State

– water depths that support wetland plants, and (3) using innovative techniques for placement of dredged material to simulate

CHAPTER 1 natural systems. Figure 7.15. Aerial view of wetland-restoration sites at State of the Bay

– Delehide Cove (left) and Starvation Cove (right) in West

Marsh-restoration and -creation projects

7 Bay. Image courtesy Google Earth. occur on several scales. Many of the

projects cover a fraction of an acre; others

CHAPTER extend to hundreds of acres. The

significance of acreage may be misleading. Projects that cover a small area may actually be quite large in terms of the amount of linear feet of newly created shoreline. It is the edge of the interface between emergent plants and water that provides the best estuarine habitat (Minello and Rozas 2002), so designs that have extensive edge habitat are currently preferred. Many of the smaller marsh-restoration projects involve planting propagules along shoreline that appears to be suitable. For larger projects with substantial funding, site preparation may include the use of heavy equipment or dredging to shape the substrate and enhance the surface topography for marsh establishment. Some of these projects in recent years have created extensive fields of terraces (e.g., Galveston Island State Park, Figure 7.14) or mounds (e.g., Delehide and Starvation Coves, Figure 7.15). Other types of projects include the formation of new substrate with dredged material. Dredged material is now commonly used for marsh restoration (e.g., on Atkinson Island in the upper bay). Some projects do not require such site preparation, but merely need protection from wave erosion and predation, for which geotextile tubes are used. Many restoration projects are the result of volunteer action by organizations with a conservation mission, such as the Galveston Bay Foundation, Scenic Galveston, and the Armand Bayou Nature Center. These types of restoration projects are labor and cost intensive, but may be accomplished by a single organization. The very large projects of 20 to 200 acres that involve participation by multiple organizations, e.g., Atkinson Island and Galveston Island State Park, are the domain of government agencies with substantial funding, e.g., the Texas Parks and Wildlife Department, the U.S. Fish and Wildlife Service and the Texas General Land Office. These large projects are essential if the goal of The Galveston Bay Plan, restoration of 8,600 acres of estuarine marsh, is to be achieved. That restoration goal has not yet been reached. However, the Estuary Program and its partners place a high priority on protecting wetlands and coastal habitats from erosion and conversion to other uses. The technology applied to marsh creation has proven successful. Placement of wave breaks around the large projects appears to improve the ability of created marshes to hold and capture sediment. Terracing or mounding provides variation in elevation, which is an important characteristic of marshes and offers habitat to many different types of species. Placement of dredged material along a shoreline increases the amount of shallow water and intertidal environment essential to establishment of smooth cordgrass, the dominant plant species in these estuarine marshes. These technical methods are expensive, but allow managers to reclaim former marshes that have been largely degraded. Wetland creation also restores freshwater wetlands in the Lower Galveston Bay watershed. Twelve agency partners and local volunteers created a storm water–treatment wetland at Mason Park on Brays Bayou (Figure 7.16). In addition to providing wildlife habitat, beauty, and a setting for outdoor education, the Mason Park wetland cleans the storm water that flows through it. Data collected over 15 months show that, State of the Bay

– on average, E. coli concentrations in water dropped from 61,229 colony-forming units (cfu) at the inlet to 7 only 278 cfu at the wetland outlet to Brays Bayou (Sipocz 2008). Constructed storm water–treatment wetlands are a win-win solution for the problem of wetland loss in developed areas and water quality

degradation; they are also cheaper to build and maintain than traditional wastewater-treatment facilities. CHAPTER

Wetland-restoration projects such as those at Galveston Island State Park, Jumbile Cove, and Mason Park are constructed to replace natural wetlands lost due to factors such as relative sea-level rise and urban and suburban land development. When carefully built, constructed wetlands can mimic the structure and function of natural wetlands. However, research shows that such is not always the case. Differences in soils and elevations can send a constructed wetland on a different successional trajectory than a natural wetland, ultimately leading to different vegetation and wildlife communities than intended (Zedler and Callaway 1999; Edwards and Proffitt 2003). Additionally, it can take many years for a well-constructed wetland to imitate its natural counterpart. Even with the drawbacks, when wetlands have already been lost, wetland restoration and construction are the only ways to replace them.

State of the Bay 2009 Bay the of State

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Figure 7.16. The constructed wetland at Mason Park on Brays Bayou. Image courtesy Texas AgriLife Extension, Photographer Milt Gray. CHAPTER 1 State of the Bay

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7 CHAPTER

Wetland Preservation Natural wetlands still exist in the Lower Galveston Bay watershed. Successful wetland-preservation projects require the cooperation of many people and organizations. Those working to preserve wetlands must undertake a set of steps to successfully complete a wetland preservation project. They must: (1) identify the location of the wetland to be preserved, such as those identified in the Galveston Bay Habitat Conservation Blueprint (GBF 1998); (2) work with landowners to negotiate the preservation of the desired land, whether by purchase of fee title or easement; (3) raise the funds from agency partners and private donors to pay for the land transaction, which may involve multiple grant applications; (4) develop a legal instrument to protect the preserved habitat in perpetuity (such as a conservation easement or deed restriction language); and (5) identify authorities that are willing to hold the title, serve as a steward to manage the land or monitor the conservation easement. Over the past twenty years, more wetland-restoration projects have been funded and completed in the Lower Galveston Bay watershed than wetland-preservation projects. Wetland restoration projects are tangible, on-the-ground, construction activities that generally can be completed in a few years and for this reason are attractive to funding organizations. In contrast, wetland preservation projects may take longer to plan and execute, and the involvement of third-party landowners with a vested interest in the outcome adds an additional layer of potential complication. While restoration and preservation are valid uses for public funding and both are needed in the Lower Galveston Bay watershed, we now know that—unlike estuarine wetlands (most of which are subject to Section 10/404 permitting)—freshwater wetlands continue to be lost faster than they are being restored or preserved. For that reason, more wetland-preservation projects should be implemented to maintain the ecological integrity of the Lower Galveston Bay watershed in the coming decades.

Seagrass Meadows

The Importance of Seagrass Communities Seagrass meadows are highly productive communities that support a diversity of life. They provide food, shelter, and nursery habitat for many commercially and recreationally important species of finfish, shellfish, and migratory waterfowl. Seagrasses are valuable for sustaining the yield of commercial and recreational species from the bay system. This ecosystem provides food resources and protective cover for a number of species and contributes detritus to the open bay bottom food web. In addition to its ecological importance, submerged aquatic vegetation (SAV) plays an important role in the physical processes of shorelines. They stabilize shoreline sediments, reduce wave energy, trap particles and nutrients, and decrease turbidity. State of the Bay

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7 CHAPTER

Trends in Seagrass Distribution The majority of Texas seagrass meadows occur along the middle to lower Texas coast (e.g., the Laguna Madre). Seagrasses typically thrive in warm, clear waters with higher salinities. Some seagrasses, like widgeon grass (Ruppia maritima) and tapegrass (Vallisneria americana), can be found in fresh water. The more halophytic (saline-adapted) species include shoalgrass (Halodule wrightii), clovergrass (Halophila engelmannii) and turtlegrass (Thalassia testudinum). Salinity, turbidity and rainfall- freshwater inflow patterns seem to be the controlling factors for natural seagrass growth in Galveston Bay (TPWD 1999). Tidal current and circulation also have an important effect on seagrass beds. This water movement cleanses the leaves of epiphytic algae and allows for greater

light penetration. Figure 7.17. Map of the distributions of seagrass beds in In the Galveston Bay system, SAV the Galveston Bay system, 1965 to 1996 (Renfro 1959; historically flourished (Figure 7.17) in Pullen 1960; Pulich 1996). 4 locations: (1) around the Trinity River Delta (widgeon grass and tapegrass); (2) along the western shoreline of Galveston Bay from Seabrook to San Leon (widgeon grass); (3) along the southern shoreline of West Bay (shoalgrass mixed with widgeon grass); and (4) in Christmas Bay (shoalgrass mixed with turtlegrass and clovergrass) (Renfro 1959; Pullen

State of the Bay 2009 Bay the of State 1960).

– Most of the seagrass beds once present in the Galveston Bay system have been lost since the late 1950s (Pulich and White 1991; Pulich 1996). The decline in habitat of this type between 1950 and 2005 was about 2,000 acres or 80 percent of the 1950s habitat (White et al. 1993; TPWD 1999; Williams 2007). CHAPTER 1

State of the Bay The probable distribution in the 1950s and the location of beds extant in the 1980s and 1990s are shown in

– Figure 7.17. A remnant population of perennial seagrass beds (excluding widgeon grass) has survived 7 continuously in Christmas Bay, including a small component of turtlegrass (Williams 2007). Submerged aquatic vegetation habitat decreased from 2,500 acres in the 1950s to approximately 700 acres in 1987. In

CHAPTER 1998 there were 424 acres in Christmas Bay (TPWD 1999), plus some amount of widgeon grass in

tributaries and upper portions of Trinity Bay. Since 1998, beds of shoalgrass and clovergrass have developed in West Bay independent of plantings, perhaps due to broadcast introductions (Pulich 2007). In 2005, there were 437 acres in Drum Bay and Christmas Bay with some additional acreage around Galveston Island State Park in West Bay. Populations exist in West Bay at this time from a combination of recolonization and planting. Widgeon grass is ephemeral and more tolerant of lower salinities. It can still be found scattered in upper Trinity Bay near the mouth of the Trinity River, in Galveston Bay tributaries, and in isolated ponds (TPWD 1999). The widgeon grass beds along the western shore of upper Galveston Bay have disappeared without remnant populations. Mysteriously, populations of this species are observed to appear, disappear, and reappear elsewhere quickly for unknown reasons. Recently, seagrass expansion in West Galveston Bay has been observed by several agency scientists with NOAA, the TPWD, and the USFWS. The expansion appears to be dominated by shoalgrass. The areas where it has been observed include the coves along the southern shoreline of the bay and along the southern edge of dredged-material-placement areas between the bay and the Intracoastal Waterway. Expansion has also been observed within restoration sites, particularly Galveston Island State Park, where approximately 200 acres of shoalgrass and clovergrass have developed.

Causes of Seagrass Loss The exact reasons for the decline in submerged aquatic vegetation are not known. Plausible reasons include: subsidence, effects of hurricanes on Galveston Bay, increase in light attenuation (the reduction in light penetration), and human activities including development, wastewater discharges, chemical spills, and dredging. Czapla (1993) indicated that light attenuation was presumably the major limiting factor to SAV growth in Galveston Bay, as in other estuaries. In addition, submerged aquatic vegetation requires a low energy environment with limited water current or turbulence. High wave energy and turbidity in locales where submerged aquatic vegetation formerly existed may reduce the potential for reestablishment. Placement of geotubes for protection of shorelines at Galveston Island State Park has certainly encouraged the growth of seagrass meadows in that location (Figure 7.14). Dunton (1999) categorized the causes of seagrass loss into natural and anthropogenic disturbances. Natural disturbances are produced by storms (e.g., hurricanes), floods, and droughts. These directly impact seagrass growth and survival through changes in turbidity and sedimentation. Anthropogenic disturbances are of 3 basic types: dredging, boating, and pollution. Dredging increases the suspended solids in the water and may harm seagrass through light attenuation or direct burial of plants. Powerboats, while not a significant threat to seagrass in Galveston Bay, can directly excavate plants and roots, leaving prop scars that take years to revegetate. Nutrient enrichment from agricultural runoff, improperly functioning sewage State of the Bay

– treatment systems, or groundwater discharged from septic-system drainage fields can lead to excessive algal 7 growth that shades the grass or leads to stressful low-oxygen conditions.

CHAPTER

Seagrass Bed Restoration and Creation In recognition of the value lost with seagrass decline, state agencies approved a Seagrass Conservation Plan for Texas (TPWD 1999). The plan recommended management actions to reverse the decline in this resource. The Seagrass Conservation Plan for Texas was reviewed and revised in 2009. Seagrass restoration is much more challenging and expensive than cordgrass restoration (Pulich 2007). Historically, restoration and creation of seagrass meadows have been quite difficult and not very successful, but recent projects using breakwaters have created suitable conditions for seagrass to reestablish. Conditions for seagrass growth may be improving. As discussed in Chapter 6, overall bay water quality has improved during the last 30 years, development along the bay shore on West Galveston Island has slowed, and sewage-treatment systems have expanded. Open-bay disposal of dredged material no longer takes place, removing a threat to seagrass populations. Beneficial use of dredged material for marsh and bird- island creation is now common. Studies have shown that planting shoalgrass can lead to restoration of a seagrass ecosystem (Sheridan et al. 1998; Pulich 2007). In 2000, a seagrass ecosystem colonized the terraces created for the marsh-restoration project at Galveston Island State Park, using 3 planting techniques: broadcast of plant material, planting of seagrass in peat pots and bare-root planting via pontoon or tractor boat. Of the 3 methods, broadcasting was found to be the most successful. Widgeon grass has been planted under experimental protocols in tidal sections of Armand Bayou with little success.

Oyster Reefs

The Importance of Oyster-Reef Communities In addition to being commercially valuable, oysters serve an important ecological role in the bay system. They stabilize the sediment, reduce turbidity by filtering particles, and provide a distinct habitat for reef organisms. The oyster-reef habitat is created by its dominant species, the Eastern oyster (Crassostrea

virginica). The shells of this filter-feeding bivalve create a hard, 3-dimensional structure that supports other organisms such as clams, serpulid worms, barnacles, and crabs. Exotic microorganisms (e.g., the Vibrio parahaemolyticus outbreak of 1998) have on occasion taken up residence in Galveston Bay oysters, making them unsuitable for human consumption. Vibrio parahaemolyticus is a naturally occurring bacterium in coastal waters of Texas and has been implicated in human-health problems. The 1998 outbreak was shown to be caused by a V. parahaemolyticus serotype native to Southeast State of the Bay 2009 Bay the of State

– Asia (Daniels et al. 2000; DePaola et al. 2000; Volety et al. 2001; Myers et al. 2003; USFDA 2005). Locations of reef and unconsolidated shell sediments have been identified by 3 studies over a period of 40 years: in the1950s (Turney 1958), in the early 1970s (Benefield and Hofstetter 1976), and in 1991 (Powell CHAPTER 1 et al. 1994). There have been no bay-wide estimates of the area of oyster reefs since 1991. The TPWD is State of the Bay

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currently mapping oyster reefs, but the impact of Hurricane Ike will cause the reef area estimates to be 7 minimal in comparison to those from previous studies.

CHAPTER

The oyster reefs of Galveston Bay can be divided into naturally occurring reefs that have existed over historic time and reefs that have been created as a result of human influences. Reefs created through human influences include those associated with placement of dredged material, oil and gas development, oyster leases, and modifications in current flow. The reef types resulting from human activity account for a substantial fraction of all of the present reefs in Galveston Bay—in many areas, 80 to 100 percent of the (Diener 1975; Powell et al. 1994). As described in Chapter 2, oysters create a reef ecosystem based on the formation of a 3 dimensional structure from the growth of the shells of the Eastern oyster (Figure 7.18). An oyster starts life as a floating egg that, upon fertilization, develops into a planktonic larva that feeds on phytoplankton. The last larval stage settles to the bottom, seeks an appropriate substrate and, if successful, Figure 7.18. Eastern oysters (Crassostrea virginica) create a 3- dimensional reef ecosystem in Galveston Bay. Image courtesy Galveston metamorphoses into a Bay Foundation. miniature oyster called spat. The environmental cues used by larval oysters involve the presence of a hard substrate, preferably the shell of an adult oyster; water movement; salinity; and food supply (Galtsoff 1964). Once metamorphosis occurs, an oyster is anchored to the substrate and has no ability to move to a new location. However, humans move oysters around the bay as part of the commercial lease program. In the past, reefs were largely undisturbed by human influence and generations upon generations of oysters settled on previous reef occupants. Historically, the height and area of the reefs in the bay were considerably greater (Figure 7.19). Oyster reefs were a major hydrological feature of Galveston Bay at the time of European colonization. Figure 7.12 shows the emergent character of Redfish Bar (see also Chapter 3). The abundance and distribution of oyster shell were significantly reduced by commercial shell dredging. However, oysters remain economically, ecologically, and hydrologically important. State of the Bay

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CHAPTER

Trends in Oyster-Reef Distribution This discussion emphasizes the trends in distribution of oyster reefs; Chapter 8 includes a discussion of the status and trends of the oyster as a fishery species. Oyster reefs, shell-dominated bay bottom, and buried “mud shell” were mapped in a survey conducted by Turney between 1954 and 1958 to obtain location and abundance information for companies engaged in dredging oyster shell (1958; Rehkemper 1969). Mining oyster shell from the bay bottom for construction and industry continued until 1969 (see Chapter 3). Benefield and Hofstetter (1976) and Powell et al. (1994) later surveyed the oyster reefs as a fishery resource. The maps produced by the 1958 and 1994 studies are reproduced in Figure 7.19. Shading indicates locations of reefs and unconsolidated shell sediments in the bay. Orange represents oyster reefs that existed during Turney’s 1954– 58 survey, but not in the 1991– 92 survey by Powell et al (1994). This shell was likely removed by shell dredging activities. Green represents oyster-reef locations

identified in the 1991–92 survey. There are large differences between the mapping done in the 1950s and the study done in the 1990s. Although the records are not available for quantification of State of the Bay 2009 Bay the of State

Figure 7.19. Oyster Reefs in Galveston Bay, 1950s to 1992. Data source – the differences, the maps in (Turney 1958; Rehkemper 1969; Powell et al. 1994). Figure 7.19 support the conclusion that the location and area of Galveston Bay oyster reefs changed considerably over the period in

CHAPTER 1 which shell dredging was permitted. For example, one of the reefs shown south of the Texas City Dike in State of the Bay

the 1950s appears to be located where a spoil island currently exists. The 1950s map shows 2 large reefs –

7 east of the mouth of Clear Lake where no reefs appear on the 1992 map. The extent of the reef complex in East Bay appears to have been much larger in the 1950s than in the 1990s. The area between Eagle Point and Smith Point has a dense complex of oyster reefs in all 3 maps, but the largest reef area appears to have CHAPTER shifted from west to east across the Houston Ship Channel.

The area of oyster reef and oyster shell bottom identified by Powell et al. (1994) was substantially greater than depicted on earlier charts from the 1950s prepared by Turney (1958; Rehkemper 1969). This may have been due to differences in survey methods used to map the reefs: the 1990s survey was done with sonar, the 1950s survey with sediment cores. Reef accretion in the 1994 study was most noticeable in 3 areas: (1) along open bay reaches of the Houston Ship Channel, (2) at the southern edge of Redfish Bar and the western extension of Hanna’s Reef, and (3) in the Dickinson Embayment. Reef loss was concentrated in 4 areas: (1) along the southern shore of Trinity Bay, (2) the western end of Redfish Bar, (3) East Bay, and (4) Shoal Point near Texas City. The greater extent of reef identified by Powell et al. (1994) can be ascribed to at least 2 factors. Some new reefs have probably formed in the 40 years since the Turney study was completed. Also, technology used by Powell et al. generated a new definition of an oyster reef and resulted in more positive classifications, particularly in deeper water. All of the past oyster-reef mapping may be of limited value in the present. The storm surge of Hurricane Ike, which inundated the bay on September 13, 2008, carried a sufficient sediment load to bury large areas of reefs. The TPWD estimates that 55 to 60 percent of the productive reefs in Galveston Bay were covered by sediment carried in the hurricane’s storm surge (FEMA 2008; Rodney 2009). In East Bay the estimate is that 80 to 90 percent of reefs were damaged by the hurricane (Rodney 2009; Tompkins 2009).

Causes of Reef Distribution Changes A few of Galveston Bay’s oyster reefs have persisted throughout recorded time; others have exhibited substantial malleability, changing position and shape over a half century or so in response to natural and human-caused changes in the bay system. Oysters respond to changes in circulation and current, phytoplankton abundance, salinity, disease, and predation. The largest impact on the reef system in the bay has been removal of shell for construction and the chemical industry. When industry and development expanded after World War II, the production of shell from fossil deposits or “mud shell” was permitted. This dredging removed shell from the substrate to depths of more than 10 feet. The mud from which the shell was obtained was disposed in the open bay waters. In some areas, the dredging removed the substrate needed for spat settlement and reef continuance. Shell-dredging during the 1960s and 1970s removed reefs from depths up to 45 feet. Mud-shell dredges removed 67.6 million cubic meters (88.4 million cubic yards) of oyster shell from Texas bays from 1962 to 1970 (Benefield 1976). There is no record of the total volume of oyster shell, either living or fossil, that has been removed from the bay. Dredging of oysters and shell from living reefs began more than a century ago and continues today. Chapter 3 discusses the early dredging of shell for construction. Before 1969, exploitation of oyster shell was the principal reason for the use of oyster dredges. Ward (1993) estimated that 135,000 acre-feet of State of the Bay

– shell was removed by shell dredgers, not oyster fishermen, between 1910 and 1969. The dredging of 7 oysters for seafood removes shell from the bay, but not in the volume removed for industry and construction, and the fishery does not remove reefs. CHAPTER

No evidence exists for a substantial impact by the commercial oyster fishery on the number and size of oyster reefs in the bay. Some of the most heavily fished reefs have not varied much in size and shape since the original surveys of Galveston Bay in the 1850s. Most heavily fished reefs have accreted more area in the past 20 years than reefs not fished. Reefs that are open or closed to harvest for public health reasons did not differ uniformly in their structure. The most significant areas of estimated reef loss were in areas of the bay closed to oyster harvesting due to public health regulations (Powell et al. 1994). There are several likely impacts on reef area from the oyster fishery. Many reefs in naturally favorable areas are accreting at their margins. An unknown amount of this marginal accretion is due to shell movement by the fishery. Most private leases today contain reef or semi-consolidated shelly areas based on shell transplanted by the lease holders. The accretion of these reef areas was dependent on siting in relation to natural factors affecting oysters. Movement of shell off of reef edges, in many cases, has appeared to aid reef growth (Powell et al. 1994). Some reefs have declined because they are no longer optimally located for productivity as a result of circulatory changes in the estuary (e.g., Carancahua Reef in West Bay). Conversely, some areas formerly with few oysters now support productive reef if satisfactory substrate is available for spat settlement. Observations suggest that reefs build slowly onto muddy bottom, due to several inhibitory processes (Wermund et al. 1989). This slow process of shell consolidation may make reefs susceptible to damage from commercial dredging during the early stages of their development. According to Powell et al. (1994), most reefs are now detached from the shoreline, a likely result of subsidence and shoreline retreat. Additionally, the increase in water depth (particularly for barrier reefs) has reduced the extent to which reefs are exposed while at the same time drowning the natural along-shore berms that can develop into reefs. Areas of high subsidence, such as the Upper bay near Clear Lake, have suffered reef attrition due to siltation. Channelization, dike construction, and the loss of Redfish Bar have substantially altered bay circulation

patterns. The pre-1900 circulation pattern in Galveston and Trinity bays is unknown, but the salinity regime must have been drastically different from today. Prior to 1900, Redfish Bar was crossed by 3 channels, only one of which (West Pass) permitted significant water interchange between the upper and lower bay systems. In all likelihood, a salinity gradient existed such that the Upper Bay system was substantially fresher than today. The breaching of Redfish Bar by the Houston Ship Channel produced major circulatory changes influencing oysters. These changes would have been particularly important in the years State of the Bay 2009 Bay the of State

– before reservoir construction and large metropolitan water discharges moderated the hydrological pattern of the Trinity River. In the early part of the last century there were times when the Trinity River had no flow in the Upper watershed. Today that would result in a nearly oceanic salinity in Trinity Bay, to the

CHAPTER 1 benefit of oyster predators and parasites such as Dermo (Perkinsus marinus) and the oyster drill (a predatory State of the Bay snail). Before World War II, Redfish Reef may have impeded the circulation of oceanic water enough to –

7 maintain moderate salinities even during low river flow. Today, the bulk of the Trinity River flow exits Trinity Bay along the southern shore, not through the

CHAPTER historical delta channels and Turtle Bay, which was isolated to become Lake Anahuac. The river flow wraps

around Smith Point, and flows across Mattie B. Reef and Tom Tom Reef, reaching nearly to the Bolivar Peninsula before becoming entrained in the seaward flowing water at Bolivar Roads. This circulation pattern has likely existed for many decades (Reid 1955; Diener 1975) but its intensity must have dramatically increased as the Houston Ship Channel became deeper and Redfish Bar ceased to function as a circulation barrier. Other changes have probably also been important. For example, the Texas City Dike has reduced circulation from Galveston Bay to West Bay. Bay-wide changes in circulation have resulted from the major dredge-and-fill projects. The Houston Ship Channel has increased the penetration of more saline water into the Upper estuary and has increased current velocities, extending the area of oyster productivity northward. Widening of the Houston Ship Channel exposed facies of buried oyster shell, providing substrate for oyster spat settlement. As a result, oyster reefs spread along the edges of the channel (McFarlane, personal communication, 2009). Over 2,500 acres of reef have developed along this channel, a substantial fraction of which occurs between the shoulders of the channel itself and the crest of the parallel disposal banks (Powell et al. 1994).

Reef Creation and Enhancement The Galveston Bay Plan calls for protection of oyster reef habitat. Oyster reefs are valued for their production of seafood, provision of resources and habitat for sport fish, and stabilization of sediment for erosion prevention and turbidity reduction. Oyster reefs have been created in new places, and the dimensions of existing reefs expanded, to increase the benefits derived from this ecosystem (Diener 1975). In one major effort, an artificial substrate was developed that could substitute for oyster shell as a cultch material, an attachment location for the metamorphosis of oyster larvae. The substrate was composed of a combination of fly ash from the combustion of coal at a local power plant and Portland cement. This large experiment consisted of the deposition of more than 12,000 cubic yards of fly-ash cement pellets in Lower Galveston Bay and at 5 other sites around the bay. The Lower Galveston Bay site was east of Eagle Point and covered 5 acres of bay bottom. Pellets were deposited in May and August of 1993. The spat set in 1994 was heavy and survival good (Baker 2001). Another reef-creation project was initiated in the Galveston Bay system in 1996. Located in Dickinson Bay, it was undertaken by the Natural Resources Conservation Service through a grant from the Galveston Bay Estuary Program. In this case, oyster reef was constructed to protect a newly created wetland. Intertidal oyster reefs trap sediment and actually enhance sedimentation. Additionally, intertidal reefs protect the shoreline from wave action and lessen erosion. Since 2001, oyster-reef creation and enhancement in the Galveston Bay system has been limited. The Galveston Bay Foundation, in collaboration with resource agencies, accomplished additional reef enhancement in Dickinson Bay (Figure 7.20 and Figure 7.21). GBF volunteers also collected spat and grew State of the Bay

– oysters on piers in locations around the Galveston Bay system. 7 CHAPTER

The devastation of the upper Texas coast by hurricanes in 2005 and 2008 has renewed interest in restoration and creation of reefs. TPWD is surveying the buried reefs in East Bay to determine which are suitable for use of dredging to expose shell for cultch and which are buried so deep that new cultch must be added. On deeply buried reefs, cultch will be mounded to encourage spat settlement. Along the western side of the bay near San Leon, oyster cultch will be provided for near-shore creation of patch reefs.

Open Bay Waters The open bay waters touch all of the habitats described above. The open bay is a continuous habitat covering an area almost identical to the surface area of the bay, but it is not a homogeneous habitat despite its appearance. The open bay habitat has a salinity gradient, variation in nutrients and sediment load, and differences in concentration of phytoplankton and other organisms. The health of the habitats discussed above is connected to the properties of the bay waters. For example, seagrass beds will not survive in turbid, high-nutrient water.

The open bay waters are the primary habitat of the bay and contain most of the large Figure 7.20. Oyster-reef enhancement project in swimming species (e.g., fish, bottlenose Dickinson Bay, 2006. Image courtesy Galveston Bay dolphin, turtles and squid). The large volume Foundation. of water provides essential services for the

dilution and disposal of pollution, moderation of climate, transportation routes, and food supply. Very few invasive species have been documented in the open bay. An exotic bryozoan (a colonial marine animal) known commonly as sauerkraut grass (Zoobotryon verticillatum) was first documented in the bay State of the Bay 2009 Bay the of State

– from TPWD samples in 2000. Sauerkraut grass is abundant in some years and can interfere with shrimp trawling. CHAPTER 1 State of the Bay

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7 Figure 7.21. Oyster spat can be seen. Image courtesy Galveston Bay Foundation. CHAPTER

The decline of oyster reefs and seagrass meadows has resulted in a larger area of open, unvegetated bay bottom than that which existed 100 years ago. Human activities in the past have been responsible for increased suspended sediment that smothered oysters and covered or shaded seagrass. The open-bay bottom of today is unstable and easily re-suspended. It appears that the damage done by Hurricane Ike to oyster reefs resulted from a combination of sandy, marine sediments being carried into the bay during the storm surge and deposition of muddy sediment during the storm surge ebb (Dellapenna 2011). Dominant species of the open bay bottom are infaunal worms, primarily polychaetes, ghost shrimp, and bivalves (e.g., clams). The species that live in this sediment are seldom monitored and there is a limited historical record that would permit determination of invasion by exotic species.

Tidal Flats White et al. (2004 ) documented the long-term, dramatic loss of estuarine or tidal flats along the backside of Galveston and Follets Island and the Bolivar Peninsula. Between the 1950s and 2002, tidal flats decreased from 5,856 acres to 1,904 acres (the absolute area of flats may vary from that determined using aerial photographs because of different tidal conditions at the time of the photography). Much of this loss is due to relative sea-level rise and the resulting conversion of flats to open water. White et al. (2004 ) also documented a similar long-term loss for this habitat in other areas of the Texas coast, especially in Corpus Christi (2006, 2008) and the Matagorda and Brownsville-Harlingen areas (2005). This habitat seems especially vulnerable to increasing rates of sea-level rise.

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7 CHAPTER

Terrestrial and Freshwater Habitats Much of the land in the Lower Galveston Bay watershed was covered in prairie when the first written accounts were made (Weniger 1984). Prairie consists of grasses and forbs (broadleaved plants) with very few trees or shrubs. Dominant species of grass in this watershed are little bluestem, big bluestem, switch grass and Eastern gamagrass. While the grasses are dominant, there are abundant herbaceous species, including many wildflowers such as Coreopsis, sunflowers, Indian blanket, Liatris, and bluebonnets (Figure 7.23). Prairie historically covered the land between the forested borders of the rivers, streams and bayous. It is estimated that 6.5 million acres of coastal prairie existed in Texas before European settlement. Now it is an endangered habitat, with less than 65,000 acres remaining (USFWS and USGS 1999). We estimate that over 500,000 acres of prairie have been lost in Harris County alone, based on the assumption that over 80 percent of the land now classified as developed was originally prairie. The loss is less in other counties. Prairie historically was developed first for agriculture, and then covered by buildings or roads.

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CHAPTER 1 State of the Bay

– Figure 7.23. Grasses are dominant in coastal prairies, but there are also abundant wildflowers

7 as seen in this native prairie near La Marque. Image courtesy Carolyn Fannon, Houston Coastal Center, Environmental Institute of Houston, University of Houston.

CHAPTER

Two hundred years ago the vast coastal prairie supported a large, diverse food web that contained buffalo and prairie chicken as well as large predators such as red wolf, black bear, cougar, and other animals. Over time, these species were replaced by humans and their domestic species. There are still deer, coyote and bobcat, but the abundance and variety of large animals is greatly reduced. Many public and private conservation organizations are engaged in acquiring and managing coastal prairie lands, primarily for the protection of bird Figure 7.24. Chinese Tallow (Triadica sebifera) forest populations including migratory (background) and new growth (foreground) invading waterfowl. The Katy Prairie Conservancy remnant coastal prairie. Image courtesy Houston Coastal Center, Environmental Institute of Houston, in western Harris County and the National University of Houston. Wildlife Refuges on East and West Bays have the largest expanses of remaining coastal prairie. Smaller tracts of prairie are managed at the Armand Bayou Nature Center, the University of Houston Coastal Center near La Marque, the Texas City Prairie Preserve, and other locations around the Lower Galveston Bay watershed. A significant threat to the remaining prairie habitat is invasion by Chinese tallow tree and other exotic plants (e.g., deep-rooted sedge). In some places Chinese tallow has changed land from prairie to a monoculture forest (Figure 7.24). Bruce et al. (1995) projected that by the year 2000, in Galveston and Brazoria counties alone, Chinese tallow forest would invade over Figure 7.25. Hackberry (Celtis laevigata) is common to riparian habitats of the Lower Galveston bay watershed. 72,000 acres of coastal prairie. Some of the Image courtesy Lady Bird Johnson Wildflower Center, 2,750 acre increase in forest and scrub- photographer Melody Little. State of the Bay

– shrub wetlands between the 1950s and 1989 was probably due to increases in 7

Chinese tallow (White et al. 1993). CHAPTER

Prairie habitats are often mosaic habitats containing seasonal wetlands that are important for treatment of storm water and biodiversity. Based on satellite images, approximately 168,000 acres of freshwater emergent wetlands are scattered throughout the remaining prairie in the Lower Galveston Bay watershed (see Table 7.3) (NOAA 2006).

Riparian Forests and Waterways Early written accounts of the watershed described the area around Galveston Bay as grassland subdivided by ribbons of woodlands along the courses of rivers, streams, and bayous. The ribbons were seldom more than a mile wide, except along the major rivers. Riparian forests developed in intimate connection with the water bodies they border. The dominant tree species in riparian woodlands around Galveston Bay are hackberry (Figure 7.25), pecan, green ash, and oaks. Along some stretches, the Trinity River is bordered by swamp and a forest of cypress and tupelo trees standing with their roots in the water. This tree-dominated habitat (Figure 7.26) is home Figure 7.26. Native riparian forest habitat along to numerous bird species, raccoon, opossum, Armand Bayou. Image courtesy Texas Department of squirrel, bobcat, and snakes. About 540,000 acres Transportation. of these forests in the 5 counties around Galveston Bay are considered wetlands (NOAA 2006). Frequent floods act to exchange sediment and nutrients. Trees regulate water temperature and stabilize the banks. Vegetated stream banks protect water quality. As with coastal prairie, riparian forest has been invaded by exotic species (Figure 7.27) including Chinese tallow, elephant ear, and other escaped State of the Bay 2009 Bay the of State

– horticultural species such as privet. Riparian forests are also under threat from development. Over

9,000 acres of forested wetland were converted to Figure 7.27. Chinese tallow and elephant ear

CHAPTER 1 some other classification from 1996 to 2005. (Colocasia esculenta) invading riparian habitat along

State of the Bay Armand Bayou. Image courtesy Brenda Weiser, Approximately 2,500 acres were developed during – University of Houston–Clear Lake. 7 that time, and more than 5,000 acres is now cultivated or grassland (NOAA 2006). CHAPTER

Riparian habitats are widely recognized for their biodiversity. When the Big Thicket National Preserve was created northeast of the Galveston Bay watershed, the design focused on acquisition of riparian corridors. There is great interest in the riparian corridors of the San Jacinto River, Spring Creek, and Buffalo Bayou for habitat restoration at this time. Bayous, streams and rivers provide freshwater habitat. These water bodies are not all the same, but will be treated together and briefly. Bayous are the remnant distributary channels of large rivers that have moved to other locations. They have limited water flow and extensive tidal influence. In contrast, streams and rivers in the Houston-Galveston region have substantial flow rates and less tidal influence. Local bayous and rivers provide significant ecological services such as habitat for fish and wildlife and freshwater to the bay. All freshwater habitats support communities of fish and invertebrates (e.g., catfish, perch, bass, and insect larvae). In the case of slow moving urban bayous, the communities have been invaded by carp and by animals from the aquarium trade, such as armored catfish (Family Loricariidae) and the island applesnail (Pomacea insularum). Perhaps the greatest impact from invasive species occurs when these water bodies are clogged with aquatic plants such as common water hyacinth (Eichornia crassipes), hydrilla (Hydrilla verticillata), water lettuce (Pistia stratiotes), and salvinia (Salvinia minima and S. molesta). Local bayous are also impacted by floodplain development and channelization and many have significant water quality concerns, particularly for contamination with fecal coliform bacteria (see Chapter 6).

Summary Wetlands, seagrass meadows, and oyster reefs are 3 important habitat types in Galveston Bay. Wetlands and seagrass meadows have declined substantially over the past 5 decades. The trend for oyster reefs appears to be one of decline followed by an increase prior to the landfall of Hurricane Ike. Most of the loss of salt and brackish marsh has been caused by relative sea level rise and subsequent conversion to open bay and barren flats. However, the loss of these estuarine wetlands appears to have been dramatically slowed during the last 10 years. Loss of freshwater wetlands continues and is of great concern. The loss is primarily associated with conversion to uplands for suburban and urban development and agricultural purposes. The storm surge associated with Hurricane Ike inundated freshwater and intermediate marshes north of East Bay. It will take time for the salinities of these wetlands to reach normal levels. Marsh restoration and creation have added a significant amount of fresh, brackish, and salt marshes, and similar efforts may be required to reestablish the freshwater marshes destroyed by Hurricane Ike. Moreover, habitat-preservation projects are needed to slow the loss of freshwater wetlands in the Lower Galveston Bay watershed. Continuous beds of submerged aquatic vegetation flourished around the Trinity River Delta, along the western shoreline of the bay from Red Bluff to San Leon, and in West Bay prior to the post–WW II period of intense dredging and poor water quality. Only a remnant of the historical habitat has been preserved in State of the Bay

– Christmas and Bastrop Bays and Trinity Bay. Suspected reasons for the decline include subsidence, effects of 7 hurricanes, increased light attenuation and human activities. Recent successful establishment of seagrass beds in West Bay suggests that water quality is once again suitable for these species. CHAPTER

The distribution and areal extent of oyster reefs in Galveston Bay have changed since the 1950s. A 1994 study reports a significant increase in extent of oyster reefs over the last 20 years. However, this has not yet replaced the large amounts of shell that were removed by shell dredging. Unfortunately this habitat was severely affected by burial from sediment carried by Hurricane Ike’s storm surge, and recovery will take years. New potential for creation and restoration of oyster reefs has been demonstrated by several projects that successfully created new reefs in Galveston Bay by addition of artificial substrate. Additional restoration projects of this type may shorten the recovery time of the habitat. Estuarine marshes and seagrass meadows have historically been the focus of restoration and mitigation efforts. These bay habitats are currently stable at present levels, in large part due to the efforts and partnership of committed bay stakeholders and successful restoration activities. Alternately, the threat to terrestrial habitats (e.g., freshwater wetlands and coastal prairies) continues largely unabated as increasing urban and suburban development is inexorably covering prairie, forests and associated wetlands. Land conservation and habitat preservation activities are difficult to fund due to the lack of non-federal matching funds, conservation landholders, and managers. Regardless, these issues must be addressed in the years to come if the habitat diversity around Galveston Bay is to be protected.

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In Texas Parks and Wildlife Department, Coastal Fisheries Branch Publication PL88 309 2 218R. Austin, Texas. Bruce, K. A., G. N. Cameron, and P. A. Harcombe. 1995. "Initiation of a new woodland type on the Texas coastal prairie by the Chinese tallow tree (Sapium sebiferum)." Bulletin of the Torrey Botanical Club no. 122 (3):215-225.

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Pulich, W. M., Jr., and J. Hinson. 1996. Coastal studies technical report No. 1: development of geographic information system data sets on coastal wetlands and land cover. Austin, Texas: Texas Parks and Wildlife Department. Pulich, W. M., Jr., and W. A. White. 1991. "Decline of submerged vegetation in the Galveston Bay system: chronology and relationship to physical processes." Journal of Coastal Research no. 7:1125- 1138. Pullen, E .J. 1960. A checklist of marsh and marine flora in area M-2. In Texas Game and Fish Commission, Marine Fisheries Division Project Reports, 1959-1960, Project No. M-2 R-2, Job No. C-2. Austin, Texas. Rehkemper, J. L. 1969. Sedimentology of holocene estuarine deposits, Galveston Bay in Galveston Bay geology. edited by R.R. and Rogers Lankford, J.J.W., editors. Houston, Texas: Houston Geological Society. Reid, G. K., Jr. 1955. "A summer study of the biology and ecology of East Bay, Texas. Part 1. Introduction, description of area, methods, some aspects of the fish community, the invertebrate fauna." Texas Journal of Science no. 7:316-343. Renfro, W. C. 1959. Checklist of the flora of area M-2. In Texas Game and Fish Commission, Marine Laboratory Reports, 1959, Project No. M-2 R-1, Job No. C-2. Austin, Texas. Rodney, W. 2009. Innovative monitoring methods for estuarine resource management and habitat restoration. In Coastal and Estuarine Research Federation 20th Biennial Conference: Estuaries and Coasts in a Changing World. Portland, Oregon: Coastal and Estuarine Research Federation. Sheridan, P. F., R. D. Slack, S. M. Ray, L. W. McKinney, E. F. Klima, and T. R. Calnan. 1989. Biological components of Galveston Bay. Galveston Bay: issues, resources, status and management. In National Oceanic and Atmospheric Administration Estuary of the Month Seminar Series No. 13. Washington, D.C. Sheridan, P., G. McMahon, K. Hammerstrom, and W. M. Pulich, Jr. 1998. "Factors affecting restoration of Halodule wrightii to Galveston Bay, Texas." Restoration Ecology no. 6:144-158. Sipocz, M. 2008. News release: innovative wetland on Brays Bayou effectively removes bacteria from polluted stormwater runoff. Texas Sea Grant/Texas AgriLife Extension Service, Wetland Restoration Team Tompkins, S. 2009. "The state of the bay: oysters may be the hardest-working creatures in the water, filters for an ocean’s lifeblood and their massive loss from Ike threatens the entire ecosystem." Houston Chronicle, Aug. 24, 2009. State of the Bay

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———. Press release: North Deer Island partners honored by presidential award 2009 [cited 7 December 2009. Available from http://www.tpwd.state.tx.us/newsmedia/releases/?req=20091203a. Turney, J. G. 1958. Shell surveys of Galveston Bay. Houston, Texas: Horton and Horton. TWDB. 2008. Groundwater wells in Texas. Austin, Texas: Texas Water Development Board. USFDA. Pathogenic Vibrio parahaemolyticus in raw oysters: quantitative risk assessment on the public health impact of pathogenic Vibrio parahaemolyticus in raw oysters. U.S. Department of Health and Human Services, Food and Drug Administration 2005. Available from http://www.fda.gov/Food/ScienceResearch/ResearchAreas/RiskAssessmentSafetyAssessment/u cm050421.htm. USFWS, and USGS. 1999. Paradise Lost? The coastal prairie of Louisiana and Texas. US Fish and Wildlife Service. Volety, A. K., S. A. McCarthy, B. D. Tall, S. K. Curtis, W. S. Fisher, and F. J. Genthner. 2001. "Responses of oyster Crassostrea virginica hemocytes to environmental and clinical isolates of Vibrio parahaemolyticus." Aquatic Microbial Ecology no. 25 (1):11-20. Ward, G. H. 1993. Dredge and fill activities in Galveston Bay, GBNEP-28. Webster, Texas: Galveston Bay National Estuary Program. Webb, J.W. 2006. Galveston Bay: Estuarine and marine habitat change analysis. Webster, Texas: Final report for the Texas Commission on Environmental Quality, Galveston Bay Estuary Program. Weniger, D. 1984. The explorer's Texas: the lands and waters. 1st ed. Austin, Texas: Eakin Press. Wermund, E. G., R. A. Morton, and G. L. Powell. 1989. Geology, climate, and water circulation of the Galveston Bay System. Washington, D. C.: Galveston Bay: issues, resources, status and

management. National Oceanic and Atmospheric Administration Estuary of the Month seminar series No. 13. Whaley, S. D., and T. J. Minello. 2002. "The distribution of benthic infauna of a Texas salt marsh in relation to the marsh edge." Wetlands no. 22 (4):753-766. White, W A., and J. G. Paine. 1992. Wetland plant communities, Galveston Bay System. Webster, Texas: State of the Bay 2009 Bay the of State Galveston Bay National Estuary Program Publication GBNEP-16. – White, W. A., T. A. Tremblay, R. L. Waldinger, and T. R. Calnan. 2004 Status and trends of wetland and aquatic habitats on barrier islands, upper Texas coast, Galveston and Christmas Bays. Final report. .

CHAPTER 1 Texas General Land Office and NOAA under GLO Contract No. 03-057. State of the Bay

– White, W. A., T. A. Tremblay, E. G. Wermund, and L. R. Handley. 1993. Trends and status of wetland 7 and aquatic habitats in the Galveston Bay system, Texas. Webster, Texas: Galveston Bay National Estuary Program Publication GBNEP-31. CHAPTER

Williams, L. Seagrasses in Christmas Bay. of the Texas Parks and Wildlife Department 2007 [cited 6 May 2009. Available from http://www.tpwd.state.tx.us/fishboat/fish/didyouknow/christmasbay.phtml. Zedler, J. B., and J. C. Callaway. 1999. "Tracking wetland restoration: Do mitigation sites follow desired trajectories?" Restoration Ecology no. 7 (1):69-73.

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