The Lower Galveston Bay Watershed: Potential Oil Spill Impacts

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1 The Lower Galveston Bay Watershed: Potential Oil Spill Impacts Lisa Gonzalez Jim Lester Houston Advanced Research Center July 13, 2010

2 Oil Near Mississippi Delta, July 4 Source: NASA MODIS

3 Local Perspective on Size of Oil Spill (on July 9) Source:

4 Oil Spill Forecasts Source: NOAA NOS, Office of Response and Restoration

5 Gulf of Mexico Currents Winter cold fronts Prevailing winds Source: NOAA, NCEP Marine Modeling and Analysis Branch

6 Will the Spill Enter Galveston Bay? NOAA trajectories based on observations and wind patterns Other factors Volume of oil released into GOM ( MGPD) Duration of spill event Rate of oil breakdown (physical, chemical and biological variables) Rate of oil evaporation Wind patterns and currents Wave action Storms/hurricanes

7 The Galveston Bay Watershed 27,000 square miles ~10 million people

8 Human Footprint in Lower GB Watershed Population of 4.3 million people 622,000 acres of developed land in 2005 Three major ports and 15,700 vessel visits in 2007 >40% of U.S. petrochemical production Commercial seafood landings: 9 million lbs. shrimp annually 3 million lbs. oysters annually Major recreational boating center

9 Regularly Occurring Oil Spills Numerous small spills every year from vessels and facilities Between : 3,746 spills reported by GLO 416,000 gallons of petroleum product Contrast to BP/GOM spill: 1.47M 2.52M GPD (per FRTG, 6/15/10) Conservative estimate; many spills are not reported * Volume of spills due to Ike not reported Number of Spills Total Spill Volume (Gallons) Number of Reported Spills Year * 140, , ,000 80,000 60,000 40,000 20,000 0 Volume of Spills Data Source: Texas GLO

10 Sensitive Shorelines Many miles of undeveloped shoreline & habitat However, much property is located along the bay shoreline Shoreline sensitivity data used for oil /hazardous chemical spill response Texas ESI data last updated in 1995 (GLO funding revision in FY2010) Concern that spill response could be hindered Data Source: Environmental Sensitivity Index, UTBEG 1995

11 Wetlands An Impacted Habitat Freshwater Estuarine Acres in , ,258 Acres in , ,452 Net Change in Acres -25, Courtesy Andy Sipocz ISTOCKPHOTO.COM

12 Data Source: NOAA C-CAP

13 Oil Spill Impacts to Estuarine Wetlands Situated at bay-land interface Short term oil coverage: Loss of emergent biomass Long term oil coverage: Death of root systems Loss of Ecological Function Nursery and forage habitat Detrital food web Erosion prevention & sediment stabilization Loss of Ecosystem Services Commercial & recreational fishing Ecotourism & nature watching Private property protection & value

14 Oil Spill Impacts to Palustrine Wetlands Inland of bay shore susceptible to storm surge Hold water, therefore long term effects more likely Loss of Ecological Function Forage habitat (e.g. birds) Soil stabilization Slow release of rainfall runoff & evapotranspiration Sequestration of water pollutants by plant biomass Loss of Ecosystem Services Ecotourism & nature watching Water storage/slow flood water release Private property protection & value Improved water quality

15 Seagrasses Seagrasses historically found in 4 locations: Trinity River Delta Western shoreline of Galveston Bay from Seabrook to San Leon Southern shoreline of West Bay Christmas Bay About 2,000 acres (80%) lost between As of 2005, about 437 acres in Drum Bay, Christmas Bay and some near Galveston Island State Park in West Bay Greatest oil spill concern would be hurricane storm surge pushing oil into Christmas Bay complex

16 Oil Spill Impacts to Oyster Reefs Ike storm surge covered 60 % of reefs with sediment (80% in East Bay ) Many areas of bay closed to oyster harvest due to high bacteria concentrations Toxins accumulate in oyster tissue and enter food web Loss of Ecological Function Loss of nursery and forage habitat Loss of filter feeders that consume phytoplankton Loss or decline of future year classes Loss of Ecosystem Services Commercial fishing/seafood Water quality Property losses due to erosion

17 Impacts to Finfish & Invertebrates Invertebrates (Crawfish, crabs, shrimp, bivalves and polychaetes) Many accumulate organic contaminants May introduce toxins to food web Commercial crab, shrimp and oyster fisheries may be impacted Finfish Mortality of larval and juvenile fish that utilize wetlands as nursery areas Losses or declines of future year classes Predator-prey relationships & food web structure Recreational fishing will be impacted Data Source: DSHS Seafood Consumption Advisories

18 Current Species Trends Blue Crab in Shrimp Trawl All Subbays Eastern Oyster in Oyster Dredge East Bay Gulf Menhaden in Shrimp Trawl Trinity Bay Atlantic Croaker Shrimp Trawl Upper & Lower Galveston Bay

19 Impacts to Birds & Mammals Mammals (swamp rabbit, beaver, raccoon, and river otter) Oil destroys insulation properties of fur Ingestion of oil - inhibition of the immune system, organ damage, reproductive effects Birds (pelicans, herons and egrets, terns, and gulls) Oil destroys insulation properties of feathers Weight of oil decreases buoyancy and ability to dive/fly Can lead to hypothermia and drowning Preening of feathers can lead to ingestion of oil Death or chronic effects such as inhibition of the immune system, organ damage, and reproduction Ground nesting species and island rookeries especially susceptible Timing important - young fledged by end of summer Migratory species in fall/winter

20 Colonial Nesting Waterbirds

21 Impacts to Dissolved Oxygen Dissolved oxygen levels declining over time Periodic localized low-oxygen conditions Increased oil concentrations may increase number of oileating microbes Decomposition of bacteria may lead to additional lowoxygen conditions

22 Toxics in Sediment HSC historical location of sediment toxicity Oil spill could increase areal coverage of toxic sediments in the bay Metals Organics

23 Impacts to Benthic Communities Some benthic invertebrates tolerant of pollutants (Oligochaetes, Steblospio) Others sensitive to pollutants Oil spill could lead to decreased benthic species diversity and increase in pollution and low-do tolerant species Contaminants could be introduced into the food web

24 In Summary Many uncertainties regarding extent of oil spill Galveston Bay is productive, but has many stressors Habitat loss Species declines Toxics in sediment and water quality issues Areas closed to oyster harvest Seafood consumption advisories Many small oil spills How resilient is the bay to anthropogenic stressors? Short-term and long-term oil spill impacts likely Additional losses of ecological function & ecosystem services likely Greatest concerns = long term Long term wetland loss Loss of forage and nursery habitats Introduction of new toxics to food web Fisheries-dependent communities oyster fishery particularly

25 Thank You - Questions? Lisa Gonzalez Research Scientist Houston Advanced Research Center (HARC) 4800 Research Forest Dr. The Woodlands, Texas lgonzalez@harc.edu Jim Lester Vice President Houston Advanced Research Center (HARC) 4800 Research Forest Dr. The Woodlands, Texas jlester@harc.edu