Browsing by Subject "Mission-Aransas National Estuarine Research Reserve"

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Climate change in the Mission-Aransas Reserve : Evaluating vulnerability of coastal ecosystem and communities using long-term data sets and development of relevant adaptation strategies. Phase 1 : Technical Report.
(2015-06) Xue, Jianhong; Stanzel, Kiersten; Palmer, Sally (Marine scientist); Buskey, Edward Joseph, 1952-
This report assesses the long-term impacts of climate changes, such as temperature and precipitation, on the Mission-Aransas National Estuarine Research Reserve fisheries and bird species, in the past several decades. Increasing annual water temperatures and declining annual precipitation were observed in the Reserve since 1978. More than 30 years of fisheries-independent data from the Texas Parks and Wildlife Department were analyzed, along with bird count data that has been collected since 1949 as part of the National Audubon Society ‘Christmas Bird Count’. Six out of the 61 fish species, and nineteen out of more than 180 bird species were identified as being more impacted by either winter freezes (fish = average minimum temperature of coldest week; bird = coldest temperature Dec 14 – Jan 5) or precipitation (fish = summer drought; birds = second half of the year precipitation for birds) on their abundances (both fish and bird) or average length (only fish) than other species in this region. This report strengthens our understanding of climate variables and their potential impact on the ecology the Mission- Aransas Estuary, and it also helps to identify climate change vulnerability assessment targets for adaptation planning.
Community characterization of the Mission-Aransas National Estuarine Research Reserve and Surrounding Areas
(The University of Texas Marine Science Institute, 2007-05) Morehead, Sally; Beyer, Tami G.; Dunton, Kenneth H.
Development of a Comprehensive Habitat Map for the Mission Aransas NERR Using the NERRS Habitat Classification Scheme: Matagorda Island, Texas
(2007-08) Beyer, Tami G.; Rasser, Mike; Morehead, Sally
The National Estuarine Research Reserve System (NERRS) developed a new hierarchical classification scheme to standardize mapping techniques and terminology throughout all its reserves. The Mission-Aransas National Estuarine Research Reserve (NERR) obtained habitat information from various sources and reclassifed habitats according to the NERRS scheme using a geographic information system (GIS). Mapping the Mission-Aransas NERR manually at a high spatial resolution was desired, but proved challenging because of its considerable size (185,708 acres) and limited accessibility to privately-owned land areas. Existing digital habitat information was identified and obtained from partner agencies in an effort to create a comprehensive habitat map of the Mission-Aransas Estuary and the adjacent watersheds. Geospatial habitat information available within the Mission-Aransas Estuary and the adjacent watersheds were identified and assessed for appropriateness of this project by the following attributes: scale, resolution, habitats identified, location, accuracy, accessibility, and temporal relevance. The University of Texas at Austin Bureau of Economic Geology (UT BEG) had a high–resolution habitat dataset of the wetlands on Texas barrier islands. A portion of this data on Matagorda Island is within the Mission-Aransas NERR boundary and was used as a case study for reclassifying data to the NERRS classification scheme. The Matagorda Island data were provided to the Mission-Aransas NERR in vector (polygon) format, and this document outlines the procedures used to reclassify this type of data. However, vector data is not the only type of data available, and an additional method of reclassification using a raster format was also explored. This document demonstrates the process of vector and raster data reclassification for geospatial habitat information. The Matagorda Island wetlands data were originally classified using the Cowardin classification scheme, which implemented codes describing specific habitats to the modifier level (Cowardin et al.1979). Reclassification of this data from a Cowardin scheme to the NERRS scheme required the data be organized into a hierarchical database structure. A look-up table was created to compare the two classification schemes. Reclassification of the vector data required the application of the join-relationship tool supplied within the GIS environment. Reclassification of the raster data required the application of the reclassification tool supplied within the GIS environment. One of the major differences in the NERR coding system to the Cowardin classification is that upland habitat is described in great detail. Since the Matagorda Island data only contained wetland habitat information, several NERR codes were not correlated to this dataset. This report documents the methods, challenges, and recommendations of reclassifying existing data to the NERRS classification scheme. It represents the first phase in the creation of a comprehensive high resolution habitat map. Future work will incorporate additional datasets for complete coverage of the Mission- Aransas NERR habitat areas
The Ecology and Sociology of the Mission-Aransas Estuary : An Estuarine and Watershed Profile
(2012) Evans, Anne; Madden, Kiersten; Palmer, Sally
The Mission-Aransas National Estuarine Research Reserve (NERR) is one of 28 national estuarine reserves created to promote the responsible use and management of the nation's estuaries through a program combining scientific research, education, and stewardship. The purpose of this document is to provide researchers and resource managers with an adequate basis of knowledge to further development of scientific studies and applied management investigations. This document describes the different physical ecosystem components, ecological processes, habitats, and watersheds of the Reserve. The Mission-Aransas NERR is a complex of wetland, terrestrial, and marine environments. The land is primarily coastal prairie with unique oak motte habitats. The wetlands include riparian habitat, and freshwater and salt water marshes. Within the water areas, the bays are large, open, and include extensive wind tidal flats, seagrass meadows, mangroves, and oyster reefs. This site profile describes each habitat by their location, type, distribution, abundance, current status and trends, issues of concerns, and future research plans. Research within the Mission-Aransas NERR seeks to improve the understanding of the Texas coastal zone ecosystems structure and function. Current research includes: nutrient loading and transformation, estimates of community metabolism, water quality monitoring, freshwater inflow, climate change and fishery habitat. Harmful algal blooms, zooplankton, coliform bacteria, submerged aquatic vegetation, and marsh grass are monitored through the System- Wide Monitoring Program (SWMP). This document also describes the climate, hydrography and oceanography, geology, water quality, and endangered species within the Mission-Aransas
Final Evaluation Findings, Mission-Aransas National Estuarine Research Reserve, May 2006 through April 2011
(2011-08) National Oceanic and Atmospheric Administration
The Coastal Zone Management Act (CZMA) of 1972, as amended, established the National Estuarine Research Reserve System (NERRS). Sections 312 and 315 of the CZMA require the National Oceanic and Atmospheric Administration (NOAA) to conduct periodic performance reviews or evaluations of all federally approved National Estuarine Research Reserves (NERRs). The review described in this document examined the operation and management of the Mission-Aransas National Estuarine Research Reserve (MANERR or the Reserve) during the period from its designation in May 2006 through April 2011. The Reserve is administered by the University of Texas Marine Science Institute (MSI). This document describes the evaluation findings of the Director of NOAA’s Office of Ocean and Coastal Resource Management (OCRM) with respect to the Mission-Aransas NERR during the review period. These evaluation findings include discussions of major accomplishments as well as recommendations for program improvement. The fundamental conclusion of the findings is that the State of Texas is adhering to the programmatic requirements of the National Estuarine Research Reserve System in its operation of the Mission-Aransas National Estuarine Research Reserve. The evaluation team documented a number of Mission-Aransas Reserve accomplishments during this review period. Within just the five years since designation, the Reserve has assembled a highly respected and knowledgeable staff, has formed numerous partnerships and collaborations that strengthen the Reserve’s outreach and program effectiveness, and has successfully built facilities and infrastructure to establish the Reserve’s presence in both the community and on the Marine Science Institute campus. This includes the Estuarine Research Center, the Wetlands Education Center, and the Bay Education Center. Since 2006 the Reserve has successfully developed several programs that support the national system. Infrastructure to support the System-wide Monitoring Program (SWMP) was completely established and implemented within a year of designation. Direct services to local decision-maker audiences were established through the implementation of a Coastal Training Program as well. At the regional level, the Reserve is participating with the other four Gulf coast reserves to support priority issues of the Gulf of Mexico Alliance, and has held climate changerelated workshops addressing community resilience and a very well-received ‘living shorelines’ workshop. The submerged aquatic vegetation and emergent marsh biomonitoring program at the Reserve is leading to the establishment of a statewide seagrass monitoring plan, while a project to assist planners and resource managers in applying ecosystem-based management principles to land use planning has created more demand for training of this type. The evaluation team also identified areas where the Reserve and its programming could be strengthened. Because the Reserve is located on the MSI campus, which has had a well established presence since 1941, and because the Reserve staff and MSI staff and faculty work together seamlessly on so many programs, the Reserve’s identity is, to many people, virtually indistinguishable from that of MSI. The Mission-Aransas NERR’s identity and its contributions locally and nationally should be clearly and consistently recognized and acknowledged by the MSI. Select MSI staff also should be given access to the “Grants Online” process, to prevent delays and confusion that sometimes arise when dealing with CZMA awards and actions for the Reserve. Finally, the Reserve should consider how to make greater use of the expertise and interests of Reserve Advisory Board members to support the Reserve’s goals and objectives.
Freshwater contributions and nitrogen sources in a South Texas estuarine ecosystem : a time-integrated story from stable isotope ratios in the eastern oyster (Crassostrea virginica)
(2012-05) Bishop, Karen Anne; McClelland, James W.; Dunton, Kenneth H.; Walter, Benjamin
Changes in freshwater inputs due to water diversions and increased urbanization may alter the function and properties of estuarine ecosystems in South Texas. Freshwater and nitrogen inputs from the Mission and Aransas rivers to the federally designated Mission-Aransas National Estuarine Research Reserve (Mission-Aransas NERR) have received considerable attention in the past few years. However, freshwater inputs from two rivers (the San Antonio and Guadalupe rivers) that combine and drain into a neighboring bay (San Antonio Bay) may also provide a substantial nitrogen source to Aransas Bay, which is within the boundaries of the Mission-Aransas NERR. In order to study the influence of the San Antonio and Guadalupe rivers, an oyster species, Crassostrea virginica, was chosen to provide time-integrated information about freshwater contribution as a nitrogen source within the bays. Chapter One addresses variations in isotope values ([delta]¹⁵N and [delta]¹³C) in oyster adductor muscle tissue from 2009-2011 along a sampling transect from the head of San Antonio Bay through Aransas Bay. Stable carbon isotope values increased linearly from approximately -25 % to -17 %, while stable nitrogen isotope values decreased from approximately +16 % to +10 % along this transect. The patterns in stable carbon and nitrogen isotope values are consistent with substantial mixing of river-supplied water and nitrogen from San Antonio Bay into Aransas Bay. Variations in nitrogen isotopic signature between periods of sustained drought and flood conditions were relatively small, suggesting that riverine nitrogen contributions were similar regardless of the amount of freshwater inflow observed during the time frame of this study. Chapter Two addresses the isotopic equilibration time for adult oyster adductor muscle tissue using a year-long transplant experiment (November 2010-November 2011). Full representation of ambient water isotopic composition in oyster adductor muscle tissues was determined to occur roughly a year after transplant. Oyster adductor muscle could therefore be useful for long-term monitoring of nitrogen contribution from freshwater sources, and would be valuable to include in concert with water sampling and analysis of other tissues that have shorter integration rates for a comprehensive view of an estuarine system.
Mission-Aransas NERR Ecosystem Based Management Tool Demonstration Project : An Integrated Approach to Land Use Planning in Aransas County
(The University of Texas Marine Science Institute, 2011-11-18) Madden, Kiersten; Morehead, Sally
Watershed export events and ecosystem responses in the Mission-Aransas National Estuarine Research Reserve
(2009-08) Mooney, Rae Frances, 1982-; McClelland, James W.; Dunton, Kenneth H.; Maidment, David R.
River export has a strong influence on the productivity of coastal waters. During storm events, rivers deliver disproportionate amounts of nutrients and organic matter to estuaries. Anthropogenic changes to the land use/cover (LULC) and water use also have a strong influence on the export of nutrients and organic matter to estuaries. This study specifically addressed the following questions: 1) How does river water chemistry vary across LULC patterns in the Mission and Aransas river watersheds? 2) How do fluxes of water, nutrients, and organic matter in the rivers vary between base flow and storm flow? 3) How do variations in nutrient/organic matter concentrations and stable isotope ratios of particulate organic matter (POM) in Copano Bay relate to river inputs? Water was collected from the Mission and Aransas rivers and Copano Bay from July, 2007 through November, 2008 and analyzed for concentrations of nitrate, ammonium, soluble reactive phosphorus (SRP), dissolved organic nitrogen, dissolved organic carbon, particulate organic nitrogen, particulate organic carbon (POC), and the stable C and N isotope ratios of the POM. The first half of the study period captured relatively wet conditions and the second half was relatively dry compared to long term climatology. Riverine export was calculated using the USGS LOADEST model. The percentage of annual constituent export during storms in 2007 was much greater than in 2008. Concentration-discharge relationships for inorganic nutrients varied between rivers, but concentrations were much higher in the Aransas River due to waste water contributions. Organic matter concentrations increased with flow in both rivers, but POM concentrations in the Aransas River were two fold higher due to large percentages of cultivated crop land. Values of [delta]¹³C-POC show a shift from autochthonous to allochthonous organic matter during storm events. Following storm events in Copano Bay, increases and quick draw down of nitrate and ammonium concentrations coupled with increases and slow draw down of SRP illustrate nitrogen limitation. Organic matter concentrations remained elevated for ~9 months following storm events. The [delta]¹³C-POC data show that increased concentrations were specifically related to increased autochthonous production. Linkages between LULC and nutrient loading to coastal waters are widely recognized, but patterns of nutrient delivery (i.e. timing, duration, and magnitude of watershed export) are often not considered. This study demonstrates the importance of sampling during storm events and defining system-specific discharge-concentration relationships for accurate watershed export estimation. This study also shows that storm inputs can support increased production for extended periods after events. Consideration of nutrient delivery patterns in addition to more traditional studies of LULC effects would support more effective management of coastal ecosystems in the future.