Just Cerfing Volume 5, Issue 8, August, 2014

Conwtenwtsw.JCRonline.org www.cNeerxft-Pjcarg.eorgJust CerfingThe Coastal Education & Research Foudation, Inc. (CERF) Official publisher of the Journal of Coastal Research (JCR) Sea-Level Rise, Inundation, and Marsh Migration:Simulating Impacts on Developed Lands andEnvironmental Systems Dr. Charles W. Finkl Dr. Christopher Makowski Barbara Russell Editor-in-Chief Assistant Editor-in-Chief Managing EditorIssue 8, AJuugsutstCe2r0f1in4g Just Cerfing Just Cerfing 1

Previous Page Table of C Just Cerfing... C In This Issue: Presiden D Sea-Level Rise, Inundation, and Marsh Migration C The Humpback Whale (Megaptera novaeangliae) Vice P Soundscape Ecology Syed Carlos da Silva Acknowledgement Just Cerfing Vol. 5, I Flood Tidal Deltaic Island in the River Murray Estuary, South AustraliaExtreme Weather Event Impacts on the Northern Gulf Coast JCR Special Issue 70 Announcement ICS 2016 Announcement Coastal Research Library Changes in Water Quality After the Construction of an Esturary Dam in the Geum River, Korea Call for Manuscripts for a Journal of Coastal Research Special Issue Beachgoers's Demands vs. Blue Flag Aims in South Africa CERF website Publish Your Photos Membership Options CERF Board of Directors JCR Editorial Board CERF Lifetime Members CERF Patron Members Current CERF Members JCR Current Issue Cover Photo 2

Contents Next PageCoastal Education & Research Foundation, Inc. [CERF] Officers of the Foundationent & Executive Director: Senior Vice President & Assistant Director:Dr. Charles W. Finkl Dr. Christopher [email protected] [email protected]: Secretary: Executive Assistant:M. Khalil Heather M. Vollmer Barbara A. Russell [email protected] 8, August 2014 3

Previous Page Table of C Sea-Level Rise, Inundation, and Mars Developed Lands and E Anna C. Linhoss†, Greg Kiker‡, Mic†Department of Agricultural and ‡Department of Agricultural and §GuanBiological Engineering Biological Engineering EstuaMississippi State University University of Florida Ponte VStarkville, MS 39762, U.S.A. Gainesville, FL 32611, U.S.A. ABSTRACT Sea-level rise is expected to affect natural and urban areas by shiftinghabitats and inundating infrastructure. To plan for a sustainable future, it isimportant to identify both human and ecological vulnerabilities to sea-levelrise. Here, we simulate impacts to urban, developed lands and environmen-tal systems from sea-level rise by analyzing land cover (surface cover) andland use (land purpose) in the Matanzas River study area in NE Florida.The Sea Level Affecting Marshes Model (SLAMM) simulated land-coverchange through wetland migration under three sea-level rise scenarios. Par-cel data, including land use classification and land valuation, was overlaidon the simulated, future land cover. Our analysis describes a 2- to 5-km-wide longitudinal band along the NE coast of Florida of expected land-coverchange where sea-level rise will likely cause inundation and wetland migra-tion. Under a 0.9-m scenario by 2100, 5,332 ha of land (5% of the studyarea) will be threatened by some type of land-cover change, and inundationwas estimated to affect approximately US$177 million in present propertyvalue. The migration of wetlands out of current areas and into new areas isof particular concern because (1) those wetlands will have to keep pace withsea-level rise, and (2) accommodation space must be available for new wet-lands to move into. Developed lands have the possibility of hindering up to6% of the area that wetlands may migrate into. These methods and findingsare important for sustainable planning under future climate change.4 Just Cerfing Vol. 5, I

Contents Next Pagesh Migration: Simulating Impacts onEnvironmental Systemschael Shirley§, and Kathryn Frank††na Tolomato Matanzas, National ††Department of Urban and Regionalarine Research Reserve Planning Vedra Beach, FL 32082, U.S.A. University of Florida Gainesville, FL 32611, U.S.A.ADDITIONAL INDEX WORDS:  Land cover change, land use change,Matanzas, Sea Level Affecting Marshes Model, SLAMM, wetlands. INTRODUCTIONCoastal communities and ecosystems are forecasted to be profoundly af-fected by sea-level rise (SLR). Global forecasts project a 33% area loss incoastal wetlands between 2000 and 2080 with 36 cm of SLR (IPCC, 2007).SLR will also affect urban, developed lands by inundating infrastructure,with 2.4% of the global population forecasted as being displaced in thiscentury (Nicholls et al., 2011). Coastal adaptation is ‘‘urgently required’’(IPCC, 2007), so to plan for a sustainable future, it is critical to identifythe areas that are most vulnerable to SLR. Assessing the impacts to urban,developed lands and environmental systems from SLR by analyzing landcover (surface cover) and land use (land purpose) is one step in that direc-tion. The threat posed by SLR is especially important for Florida because of itslow topography, extensive coastline, valuable natural areas, and large coastalpopulations. Ten percent of the land in the state is less than 1 m above sealevel, and Florida is one of four states in the United States that account for80% of the total low-lying land that will likely be affected by SLR (Titusand Richman, 2001; Weiss and Overpeck, 2003). Florida has one of thehighest numbers of endemic species in North America (n = 413) (Land-Issue 8, August 2014 Continued on Next Page 5

Previous Page Table of C Sea-Level Rise, InundatioScope, 2014; Noss, 2011), including federally listed species, such as the Floridascrubjay (Aphelocoma coerulescens), the Florida scrub lizard (Sceloporus woodi),and the Florida golden aster (Chrysopsis floridana), each of which depends oncoastal habitat. Additionally, more than 75% of Florida’s human populationlives in counties that abut the coast, 86% of Florida’s gross domestic product isfrom coastal-related economics (Wilson and Fischetti, 2010; Wyman, Carter,and Weber, 2010), and 80% of the contributions to Florida’s economy comefrom counties that abut Florida’s coastline (Kildow, 2008). Thus, planning forSLR in Florida is especially crucial for ensuring both the environmental andeconomic stability of the state. Models have been widely used to simulate a wide variety of effects fromSLR. Bathtub-style models simulate simple inundation (conversion to openwater) based on topography and SLR scenarios (Dasgupta et al., 2009; Titusand Richman, 2001). Models that assess additional ecological processes, suchas the Sea Level Affecting Marshes Model (SLAMM), can simulate both inun-dation and wetland responses to SLR (Chu-Agor et al., 2011; Geselbracht etal., 2011; Glick et al., 2013; Temmerman et al., 2004). Several other modelsalso explore the combined biophysical and socioeconomic effects from SLR(Feagin et al., 2010; Hinkel and Klein, 2009; Hinkel et al., 2012; Linhoss etal., 2013), and other models assess species level responses to SLR (Mendoza-González et al., 2013; Morris et al., 2002). Mcleod et al. (2010) provide areview of SLR models and describes their physical, ecological, and socioeco-nomic inputs and outputs. We extend the body of SLR research to assess spatial wetland dynamicsand inundation as a result of SLR within the context of natural and humancommunities and economics. This approach allows for a more integrative as-sessment of the effects of SLR through assessing the combined impacts fromchanges to habitat composition, the aerial extent of influence, and the cost peracre of affected areas. The goal of our study was to assess the effects of SLR on urban, developedlands as well as environmental systems in the Matanzas area in NE Florida.We assessed impacts to land use and land cover by considering the net change6 Just Cerfing Vol. 5, I

Contents Next Pageon, and Marsh Migrationin area for wetlands, the migration or relocation of wetlands into and outof areas, and the migration of wetlands onto developed lands. We assessedthe impacts to developed lands by calculating the area of inundation andwetland migration and the associated cost per area for individual land uses.The specific objectives of this research were to (1) simulate inundation andwetland migration under a range of SLR scenarios in Matanzas, Florida usingSLAMM, (2) use land cover (surface cover) to infer impacts to environmentalsystems, and (3) use existing land use (land purpose) to infer impacts to hu-man communities.Figure 1. Map of the Matanzas Watershed study area showing relative elevation, cit-ies, and the Guana Tolomato Matanzas National Estuarine Research Reserve (GTM-NERR).Issue 8, August 2014 Continued on Next Page 7

Previous Page Table of C Sea-Level Rise, InundatioFigure 2. Composition of land use within the study area, including residential, com-mercial, industrial, agriculture and timber, institutional, government, and miscel-laneous land uses. Note that agriculture and timber areas are largely located in thewestern portion of the study area, outside of the impacts from sea-level rise. 8 Just Cerfing Vol. 5, I

Contents Next Pageon, and Marsh MigrationFigure 3. The locations of land-cover change as a result of wetland migration andinundation shown for each sea-level rise scenario (0.2, 0.9, and 1.6 m) between2008 and 2100. This map shows a band of change running longitudinally along thecoastline varying in width from 2 to 5 km. Areas are affected further inland alongtidal rivers.Issue 8, August 2014 Continued on Next Page 9

Previous Page Table of C Sea-Level Rise, InundatioFigure 4. The net change in wetland area under the 0.2-, 0.9-, and 1.6-m sea-levelrise scenarios. These data assume that wetlands cannot migrate onto developedlands. The values in parenthesis on the x-axis represent the area for the land-covertype under the initial condition.10 Just Cerfing Vol. 5, I

Contents Next Pageon, and Marsh MigrationFigure 5. The migration of wetland out of old areas and into new areas. This figureshows the percentage of area gained (+) and lost (-) for each wetland land-covertype under the 0.9- and 1.6-m sea-level rise scenarios by 2100. Data are not shownfor 0.2 m because of the relatively small effects under that condition. The positivevalues (cool tones) describe gains to land-cover types through migration into newareas and the negative values (warm tones) describe losses to land-cover types asthey move out of their original area, as described in the initial condition. Thesedata assume that wetlands cannot migrate onto developed lands. The values in pa-renthesis on the x-axis represent the area for the land-cover type under the initialcondition.Issue 8, August 2014 Continued on Next Page 11

Previous Page Table of C A Sea-Level Rise, Inundatio Figure 6. (a) Area of land affected from inund egory under the 0.2-, 0.9-, and 1.6-m sea-level dollars ($) per hectare of areas affected from in category under the 0.2-, 0.9-, and 1.6-m sea- culture, Comm= commercial, Govt= governm miscellaneous, Res = residential. To access this full JCR Re http://www.jcronline.org/doi/abs/112 Just Cerfing Vol. 5, I

Contents Next Pageon, and Marsh Migration B dation and wetland migration per land-use cat- l rise scenarios.(b) Cost per area in million U.S. nundation and wetland migration per land-use -level rise scenarios. Abbreviations: Ag = agri-ment, Ind= industrial, Inst= institutional, Misc=esearch Article, please visit 1310.2112/JCOASTRES-D-13-00215.1 Issue 8, August 2014

Previous Page Table of C Oil Industry and in the Hump (Megaptera n Soundscape E Southweste Breeding14 Just Cerfing Vol. 5, I

Contents Next Paged Noise Pollutionpback Whalenovaeangliae)Ecology of theern Atlanticg GroundIssue 8, August 2014 15

Previous Page Table of COil Industry and Noise Pollution in the Hu Soundscape Ecology of the Southw Marcos R. R Instituto Baleia Jubarte Praia do Forte, Mata de São João Bahia 48280-971, Brazil ABSTRACT The present work aims to assess acoustic overlapping between the humpbackwhale song and anthropogenic sounds around oil and gas platforms throughspectral description and frequency comparison. Whales were monitored sys-tematically in northeastern Brazil (11° S, 37° W to 14° S, 38° W). Acousticand behavioral data were collected from 2007 to 2009, focusing on humpbackoccurrence around oil platforms. Diverse anthropogenic noises were registeredin a similar frequency range as recorded cetacean sounds, which suggests over-lapping of acoustic niches. Noise pollution from oil and gas production maypotentially affect this species' communication, with implications for distri-bution and behavior in their breeding area. This paper is the first report ofacoustic overlapping of oil platforms and cetaceans in the southwestern At-lantic Ocean. Given increasing gas and oil exploitation, efforts to improve thedevelopment and use of these acoustic methods are recommended in order tomitigate impacts on the marine life.ADDITIONAL INDEX WORDS:  Cetaceans, anthropogenic noise, oil plat-forms, acoustic monitoring, Brazilian coast INTRODUCTION Noise may be defined as a sound that interferes with signal reception, poten-tially affecting animal ecology by disturbing common behavior (Richardson etal., 1995). The marine acoustic environment is composed of diverse sources16 Just Cerfing Vol. 5, I

Contents Next Pageumpback Whale (Megaptera novaeangliae)western Atlantic Breeding GroundRossi-Santos Centro De Biociências Universidade Federal do Rio Grande do Norte Rio Grande do Norte 59072-970, Brazilof noise, which are reflected in the varied acoustic perceptions and behavioralresponses of different animal species, mainly vertebrates (Cato and McCauley,2002; McCauley et al., 2000a,b; Miller et al., 2000).Noise in the Marine Environment The acoustic environment that whales experience today is different fromthat which they faced about 50 years ago (e.g., Andrew, Howe, and mercer,2002), during the main whaling period. Tropical breeding areas have beenespecially changed due to increases in the human population. The animalsspend about six months per year at tropical latitudes, finding a reproductivepartner, breeding, giving birth, and taking care of young until the next migra-tion to the poles (e.g., Clapham, 1996). Increases in the human population, concentrated in coastal zones, haveresulted in increased boat-ship traffic and oil drilling. The resultant acousticpollution levels may harm individual animals, causing temporary or even per-manent injuries to their physiology and behavior (e.g., Johnson et al., 2007;Richardson et al., 1995).The Humpback Whale The humpback whale, Megaptera novaeangliae (Borowski, 1871) (Cetacea,Balaenopteridae), is a cosmopolitan cetacean species distributed throughoutoceans worldwide (Clapham and Mead, 1999). As migratory animals, theymove yearly from high-latitude feeding areas, where they stay during the au-tumn and summer, to the breeding areas in the tropics, where they stay duringIssue 8, August 2014 Continued on Next Page 17

Previous Page Table of C Humpback Whale (Megaptera nthe spring and summer (Clapham and Mead, 1999). Humpback whales from the denominated ‘‘Breeding Stock A/BSA’’ (IWC,1998) occur in Brazilian waters along a range of about 6000 km (Danile-wicz et al., 2009; Lodi, 1994; Rossi-Santos et al., 2008; Tollenare, 1961;Wedekin, 2011), with the main breeding area in the Abrolhos Bank, BahiaState (Andriolo et al., 2006 a,b; Martins et al., 2001; Wedekin et al., 2010).Soundscape Ecology and Behavior: Importance of Sounds for Whales Landscapes can be defined as functional ecological spaces where the ob-served patterns reflect the interactions between natural and anthropogenicprocesses (Wiens, Stenseth, and Van Horne, 1993; Wu, 2006). The acousticenvironment is a landscape attribute composed by the heterogeneous distri-bution of objects and resources and their potential rearrangement throughtime, describing the spatial structure required to detect changes resultingfrom these interactions (Mazaris et al., 2009). Schafer (1977) was the first to define ‘‘soundscape’’ as the acoustic environ-ment composed by a variety of sounds originating from different sources,such as natural and anthropogenic, emphasizing the way this environmentis perceived and understood by any human or nonhuman individual, or bythe society (Truax, 1999). For instance, animals perceive their environment across many spatial scalesat the same time, where background noises correspond to the long-range(coarse-scale) perception of environmental cues, while foreground soundscorrespond to the short-range (fine-scale) perception of the environment(Mazaris et al., 2009). Soundscape ecology represents a new branch of ecology, and it is theresult of the integration of different disciplines such as landscape ecology,bioacoustics, acoustic ecology, biosemiotics, and others (Farina, 2014; Pi-janowski et al., 2011). It is defined as the acoustic context resulting fromnatural- and human-originated sounds, and it is considered a relevant envi-ronmental proxy for animal and human life. The humpback whale is also known as ‘‘singer whale’’ because of its uniquecharacteristic of exhibiting a singing behavior, performed only by males, dur-18 Just Cerfing Vol. 5, I

Contents Next Pagenovaeangliae) Soundscape Ecologying their breeding season. Since the 1970s, many studies have described theacoustic structure of these songs (e.g., Arraut and Vielliard, 2004; Helweg etal., 1998; Maeda et al., 2000; Payne and McVay, 1971). Humpback whale song probably functions to attract females (e.g., Smithet al., 2008) and/or to repel other males (e.g., Tyack and Whitehead, 1983;Weinrich, 1995). The song consists of single notes that form repetitivephrases called themes, and different themes form a song (Payne and McVay,1971). Probable functions of humpback whale songs at the population ecologylevel, such as stock recognition by songs and cultural exchange betweenadjacent populations, have been reported (Darling and Souza-Lima, 2005;Dawbin and Eyre, 1991; Eriksen et al., 2005; McSweeney et al., 1989; Winnet al., 1981). However, many other aspects of the soundscape ecology of thespecies during singing behavior are still unknown, such as the song relationwith the acoustic environment in which it is produced and also the diversesound sources such as the anthropogenic noise also occurring during thebreeding season. In this study, I aim to contribute to the subject of the humpback whalesoundscape ecology, describing and comparing, through time and frequencyanalyses, the acoustic niche of the whale songs and the anthropogenic noisein the southwestern Atlantic Ocean breeding ground, off the Brazilian coast.The Oil Industry in BrazilPetrobras, a state-owned company created by the Brazilian government in1954, initially held a monopoly on the Brazilian oil industry (Kimura, 2005).The early 1950s was marked by the discovery of many oil reserves aroundthe globe. Despite oil formation in roughly 3 million km2 of sedimentarybasins throughout the country, foreign oil companies pursued interests else-where and did not compete with Petrobras for Brazilian oil reserves (Matz,2000). International economic crises in the late 1980s and early 1990s caused in-creased investments in the energy sector, initiating many fusions with othercompanies to reduce costs and to enhance productive scale (Kimura, 2005;Issue 8, August 2014 Continued on Next Page 19

Previous Page Table of C Humpback Whale (Megaptera nMatz, 2000). The Brazilian law 9.478 repealed the Petrobras monopoly, authorizing othercompanies to drill in the Brazilian territory. This attracted a competitive mar-ket, which is increasing year by year (ANP, 2003; Machado, 2004). The present work aims to make an acoustic analysis of anthropogenic noiseoriginating from oil and gas exploitation in the Brazilian breeding ground forthe humpback whale, as this endangered species is considered to be an impor-tant top predator in the marine ecosystem. Potential overlapping of the whaleacoustic niche with these sounds is also analyzed and discussed. Figure 1. The study area, located between Itacarè, Ba- hia State (14° S, 38° W), and Aracaju, Sergipe State (11° S, 37° W), northeastern Brazil, presents a narrow conti- nental shelf as the main oceanographic feature, attract- ing humpback whales (Megaptera novaeangliae) to breed close to the coast, where oil exploitation is increasing. Gray squares represent oil exploitation blocks, while star points represent the recorded platforms inside the study area. The Abrolhos Bank is indicated, as it is a concentration area of humpback whale distribution in Brazil.20 Just Cerfing Vol. 5, I

Contents Next Pagenovaeangliae) Soundscape EcologyIssue 8, August 2014 Continued on Next Page 21

Previous Page Table of C Humpback Whale (Megaptera n Figure 2. The oil and gas industry produces anthropogenic noise in the mar noise sources, mostly related to the platforms, such as the perforation proces moving around (photos: M. Rossi-Santos).22 Just Cerfing Vol. 5, I

Contents Next Pagenovaeangliae) Soundscape Ecologyrine environment in the course of daily operation. There are several differentss and the metallic structure sound reflection, but also related to supply boatsIssue 8, August 2014 Continued on Next Page 23

Previous Page Table of C Humpback Whale (Megaptera n Figure 3. A spectrogram is an important graphic visualization of the time and frequ pogenic noise (<1 kHz), from the gas platform, probably originating from large eng24 Just Cerfing Vol. 5, I

Contents Next Pagenovaeangliae) Soundscape Ecologyuency relation in the acoustic analysis. Here it is presented for low-frequency anthro- gines, with pulsed vertical lines surpassing the recording limit of 48 kHz.Issue 8, August 2014 Continued on Next Page 25

Previous Page Table of C Humpback Whale (Megaptera n Figure 4. During the gas platform perforation process, a continuous noise was regist surpassing the limit of 47 kHz, indicating a broad frequency range for the anthropo26 Just Cerfing Vol. 5, I

Contents Next Pagenovaeangliae) Soundscape Ecologytered, with larger energy up to 15 kHz and horizontal harmonic bands, wave shaped,ogenic sounds at sea.Issue 8, August 2014 Continued on Next Page 27

Previous Page Table of C Humpback Whale (Megaptera n Figure 5. Spectrogram showing another type of anthropogenic noise from a gas p related to the perforation process. Discrete pulsed lines in higher frequencies ind28 Just Cerfing Vol. 5, I

Contents Next Pagenovaeangliae) Soundscape Ecologyplatform, concentrated in horizontal bands with frequencies lower than 8 kHz, alsodicate farther pulsed sounds, such as those from an engine noise.Issue 8, August 2014 Continued on Next Page 29

Previous Page Table of C Humpback Whale (Megaptera n Figure 6. In this spectrogram, it is possible to identify a noise with frequencies bet indirect from the platform because it is formed as a result of diverse chains and m30 Just Cerfing Vol. 5, I

Contents Next Pagenovaeangliae) Soundscape Ecologytween 1 and 12 kHz, heard as a pulsed and ‘‘metallic’’ sound. This was consideredmetallic cables moving with the sea currents.Issue 8, August 2014 Continued on Next Page 31

Previous Page Table of C Humpback Whale (Megaptera n Figure 7. A frequency overlapping of anthropogenic noise from the gas plat simultaneous with the low-frequency humpback whale notes (>1 kHz). Bla32 Just Cerfing Vol. 5, I

Contents Next Pagenovaeangliae) Soundscape Ecologytform is represented in this spectrogram, showing a continuous wave pattern,ack rectangle is noise range, and white rectangle is a whale song part.Issue 8, August 2014 Continued on Next Page 33

Previous Page Table of C Humpback Whale (Megaptera n Figure 8. A frequency overlapping of anthropogenic noise from the gas pl simultaneous with the low-frequency humpback whale notes (>1 kHz). Bl34 Just Cerfing Vol. 5, I

Contents Next Pagenovaeangliae) Soundscape Ecologylatform is represented in this spectrogram, showing a cross and loud pattern,lack rectangle is noise range, and white rectangle is a whale song part.Issue 8, August 2014 Continued on Next Page 35

Previous Page Table of C Humpback Whale (Megaptera n To access this full JCR Res http://www.jcronline.org/doi/abs/1036 Just Cerfing Vol. 5, I

Contents Next Pagenovaeangliae) Soundscape EcologyFigure 9. Comparison between anthropogenic noises (dark-gray points) andhumpback whale (Megaptera novaeangliae) (light-gray points) acoustic pa-rameters showing the frequency overlapping between noise and whale sounds:(A) Frequency in Hz (mean values from Tables 1 and 2 for minimum, cen-tral, and maximum frequencies). (B) Amplitude in Hz (minimum, mean, andmaximum).search Article, please visit: 370.2112/JCOASTRES-D-13-00195.1 Issue 8, August 2014

Previous Page Table of C The Coastal Education and proudly acknowledges one of our Professor Dr. Carl • e-GEO Director • Coordinator of the Master in Management Planning-FCSH-UNL • Assistant Professor, Department of Geography and Regional Planning, School of Social and Human Sciences, New University of Lisbon38 Just Cerfing Vol. 5, I

Contents Next PageResearch Foundation (CERF)r greatest international supporters:los Pereira da Silva e-GEO, Research Centre for Geography and Regional Planning, Faculdade de Ciências Sociais e Humanas, Universidade Nova de Lisboa, founded in 1981, integrates 86 researchers, of which 34 with Ph.D. and 22 Ph.D. stu- dents. Most of the researchers belong to the teaching staff or are former students of the Department of Geography and Regional Planning of the Faculdade de Ciências Sociais e Humanas, Universidade Nova de Lisboa, the Home Institution. Research activities of e-GEO are supported financially by the Fundação para a Ciência e a Tecnologiawith funds from the Portuguese Government Budget. The RI also develops projects and actions financed by national re- search funds as well as by the Research Framework Programmes of the Eu- ropean Commission and other international funds in partnership with sci- entific institutions in European and non-European countries. Please visit the following website for more information: http://fcsh.unl.pt/e-geo/?q=en/investigador/carlos-pereira-da-silvaIssue 8, August 2014 39

Previous Page Table of C Rapid Evolution Deltaic Isla River Murra South Au A Canary in River Man40 Just Cerfing Vol. 5, I

Contents Next Page of a Flood Tidal 41and in theay Estuary,ustralia: the Cage ofnagement Issue 8, August 2014

Previous Page Table of C Rapid Evolution of a Flood Tidal Delta South Australia: A Canary in th Kristine F. James, Robert P. B Geography, Environm University of Adelaide South Australia 5000, ABSTRACT Bird Island, at the oceanic outlet of Australia's largest exoreic river sys-tem, the Murray-Darling, did not exist before 1940. Originally, flood tidalsediments were moulded by tides, waves, wind, and river flows in the back-barrier lagoon, landward of the migrating River Murray Mouth. The estuarywas fluvially dominated, and the terminal lakes were mainly fresh. Follow-ing more than a century of European settlement and freshwater abstraction,salinity levels increased, prompting the construction of barrages (completedin 1940) near the Murray Mouth to restore the former predominantly fresh-water character of the estuary. Further reduced river flows, a restricted tidalprism, and management strategies produced irreversible changes in the dy-namics of the River Murray Mouth. These are archived in the landforms andvegetation of Bird Island. By the mid-1950s, sand shoals were enlarging anda small patch of vegetation was established, forming the core of an incipi-ent island. Progressively, dunes and salt marshes were established, reflectingintimate associations between landform evolution, vegetation colonisation,and island stability. As the mouth migrated to the NW, so did the flood tidalshoals, the sources for newer generations of dunes, thereby developing aclockwise establishment of dunes on the expanding island. Approximately 1km in diameter and carrying more than 80 plant species, Bird Island assistedmouth closure in 1981. During the 2002–10 drought, dredging maintained42 Just Cerfing Vol. 5, I

Contents Next Pageaic Island in the River Murray Estuary,he Cage of River ManagementBourman, and Nick Harveyment and Population e, Adelaide , Australiathe mouth and improved lagoonal water quality. Subsequent healthy riverflows cleared the mouth, highlighting the important role of river flows inmaintaining oceanic access, and sediment removal, while flushing the riversystem. The evolution of Bird Island as documented in this study demon-strates how anthropogenic activities can cause rapid and irrevocable changesto coastal–estuarine environments.ADDITIONAL INDEX WORDS:  Freshwater extraction, landform evolu-tion, vegetation colonisation. INTRODUCTION Bird Island occurs landward of a tidal inlet, the Murray Mouth in theRiver Murray Estuary, Encounter Bay, South Australia (Figures 1 and 2).The Murray Estuary, which includes the Coorong Lagoon and Lakes Al-exandrina and Albert, is a Ramsar Wetland of International Importance(Natural Heritage Trust, Australia, and South Australian Department forEnvironment and Heritage, 2000). The Murray Estuary formed follow-ing submergence of Pleistocene inter-dunal corridors, a combined resultof tectonic subsidence and relative sea level rise following the Last GlacialMaximum, culminating about 7000 years ago (Bourman et al., 2000; Mur-Issue 8, August 2014 Continued on Next Page 43

Previous Page Table of C Flood Tidal Deltaic Island iray-Wallace et al., 2010). Originally some 750 km2 (Bourman and Barnett,1995), regulation of the River Murray reduced the tidal prism by 90%(Harvey, 1996). Together with the diversion of more than 75% of freshwa-ter flows from the system, this has transformed plumes of migrating floodtidal deltaic sediments into a permanent, vegetated island. The island thusrecords the changing vibrancy of the entire river system, especially its ter-minal estuary. The formation of sand dunes and salt marsh flats on Bird Is-land are closely related to the migration of the Murray Mouth, because thisaltered the location of sand sources necessary for island expansion. Further-more, the establishment of dune and marsh vegetation on the island notonly fixed landforms in place; the salt marshes also inhibited sand drift andinfluenced the locations of successive major dune forms. An Olearia axil-laris–Leucopogon parviflorus dune vegetation community and two mainmarsh communities comprising Sarcocornia quinqueflora–Suaeda australisand Juncus kraussii–Sporobolus virginicus was identified on the island byCarruthers (1991, 1992). Bird Island encompasses dune, marsh, and sand flat landforms and vege-tation communities of varying ages, displaying different morphologies andorientations; they represent phases in the progressive but rapid expansionof the island. Bird Island thus presents a unique opportunity for the studyof the relationships between landform development and plant colonisationin a coastal–estuarine setting. Following the closure of the Murray Mouth in 1981, Bourman andHarvey (1983) were the first authors to describe the factors leading to theformation and development of its flood tidal delta into a permanent island.Three decades on, we build upon this work and the subsequent researchof others (Bourman and Barnett, 1995; Carruthers, 1991, 1992; James,2004a) to provide a comprehensive analysis of the rapid biogeomorphicevolution of this former flood tidal delta.Environmental Setting The Murray Mouth is flanked by the double-reversed spits of Sir Rich-ard and Younghusband Peninsulas, coastal sand barriers separating the SEIndian Ocean from the back-barrier lagoons of the Goolwa Channel and44 Just Cerfing Vol. 5, I

Contents Next Pagein the River Murray Estuary Figure 1. The Murray Darling and Clarence and Brisbane Rivers.the Coorong Lagoon (Figure 2). Long-wavelength swell waves transportsand towards the Murray Mouth from opposite directions (Bourman andMurray-Wallace, 1991) and determine the general location of the mouth,but its precise position is influenced by local storm waves and tidal andriver flows. In particular, river flow is significant in breaching what wouldotherwise be a continuous coastal barrier system (Bourman and Murray-Wallace, 1991; Shuttleworth et al., 2005). Between 250,000 and 1 milliontonnes of sand are moved annually along the coast by wave action (Harvey,1996) providing the sediment for the growth of Bird Island and for theblockage of the Murray Mouth. In contrast, the River Murray contributesonly limited sediment to the mouth region, resulting in the absence of aIssue 8, August 2014 Continued on Next Page 45

Previous Page Table of C Flood Tidal Deltaic Island iclassic river delta (Bourman and Murray-Wallace, 1991; Murray-Wallace etal., 2010). Mainly suspended and solution loads are carried by the river tothe sea; any bedload is usually deposited within the river before reachingLake Alexandrina, where most other sediment settles out (Johnston, 1917). The Murray Mouth is currently characterised by a micro-tidal, high-wave-energy regime that produces a wave- and tidally dominated inlet with a largeflood tidal delta but without an associated ebb tidal delta. In contrast, underpre-European conditions, the mouth was river dominated (Shuttle-worth etal., 2005; Walker, 2002). The open ocean experiences a tidal range of about0.8 m at Victor Harbor (Ports Corp South Australia, 2001). In the estuary,however, the tidal range is greatly reduced by the restriction of the Mur-ray Mouth. For example, Johnston (1917) noted a difference of 0.55 m be-tween the tidal range (spring tide) at Victor Harbor and that in the estuary,highlighting the ineffectiveness of ebb tides in permanently maintaining themouth. Occasional extreme tidal ranges, affected by meteorological condi-tions, of 2.18 and 1.30 m have been recorded for Victor Harbor and insidethe mouth, respectively (Radock and Stefanson, 1975). Combined high tides,low barometric pressures, storm conditions, and strong onshore winds occa-sionally produce storm surges (Haslett, 2000) that form washover fans andflood tidal plumes and may help to clear the mouth. For example, a stormsurge during the 1981 mouth closure cut a channel through the distal sectionof Younghusband Peninsula but quickly became clogged with sediments. Persistent year-round, moderate- to high-energy swell waves approach theMurray Mouth from the SSW, with a period of about 14 to 15 seconds, andarrive approximately parallel to the shore, whereas storm waves, with a periodof 6 to 8 seconds, usually approach the coast from the SW (Bourman, 1979;Short and Hesp, 1980). Wave heights commonly exceed 3 m. The high waveenergy at the mouth appears to be related to a steep offshore gradient, whichinvolves a loss of only 20% in wave power, compared with more than 70% atLacapede Bay to the south (Short and Hesp, 1980). The hydrodynamics ofthe Murray Mouth, particularly the high-energy wave climate and the tidalregime, play an integral role in the delivery and redistribution of sediment atthe mouth and its transfer to Bird Island.46 Just Cerfing Vol. 5, I

Contents Next Pagein the River Murray EstuaryFigure 2. The study area. Stranded beach–dune barriers and intervening interdu-nal corridors dominate the SE section of the map. Weighted wind resultant dia-grams constructed using the formula of Landsberg (1956) show the aeolian sand-shifting capabilities for localities near Victor Harbor and Meningie. Individualvectors are shown as continuous lines, and resultants are shown as dotted lines(Bourman and Murray-Wallace, 1991). The enlargement shows the locations ofthe barrages across the discharge channels of the Murray Estuary (Bourman andBarnett, 1995).Issue 8, August 2014 Continued on Next Page 47

Previous Page Table of C Flood Tidal Deltaic Island i Weighted wind resultant diagrams indicating the sand-shifting capabili-ties of winds exceeding 16 km h-1 are shown in Figure 2. They are calculat-ed using the formula of Landsberg (1956) from wind data collected at Vic-tor Harbor and Meningie. The resultants (dotted lines) of the individualvectors (continuous lines) approach the coast from the SW quarter; this isreflected in the orientation of parabolic dunes and the migration of trans-verse dunes across the coastal barriers into the back-barrier lagoons. Thiswind regime constructed the dunes on Bird Island and aided the build-upof sand across the mouth during the 1981 closure (Bourman, 1986). The Murray Mouth is a dynamic coastal inlet. Its natural dynamism isexpressed in part by its migration along the coast. Since 1839, the mouthhas migrated through an extreme range of about 2 km (James, 2004a,b).Remnants of prehistoric flood tidal deltas occur either side of the presentMurray Mouth (Bourman and Murray-Wallace, 1991) and suggest mouthmigration of up to 6 km over a period of at least 3000 years. Comprisingwaterlogged and submerged soils, these fossil flood tidal deltas are vegetatedby sedge and lignum communities (Edyvane et al., 1996). No dunes occuron these abandoned deltas; the shoals were probably too dynamic to allowtime for dune construction and stabilisation by vegetation. The growth ofmarsh vegetation on these palaeodeltas was probably only achieved aftermouth migration and abandonment of the flood tidal sediments.The estuary originally had a large tidal prism with a significant head dueto its connection with Lake Alexandrina. The barrages, however, have re-duced the tidal prism by some 90% (Harvey, 1996). Using surveys of theMurray Mouth undertaken before barrage emplacement, James (2004a)noted that over the 100 years between 1839 and 1938, even with low riverflows, and particularly after storms, the ebb current assisted in maintain-ing the mouth. Before barrage construction, unvegetated flood tidal deltasand plumes, lobes, or associated features appeared as relatively persistentfeatures, but at no time did conditions prevail that allowed them to be-come permanently vegetated; furthermore, during major flood events suchas that of 1870, the sand plumes were removed (Bourman and Barnett,1995; James, 2004a, b). Thus, strong river flows are essential to fully clear48 Just Cerfing Vol. 5, I

Contents Next Pagein the River Murray Estuarythe mouth, because the ebb tides are incapable of completely removing theflood tidal sediments. Marked reductions in river flows related to upstreamabstractions, coupled with tidal amplitude attenuation, as well as barragemanagement strategies, resulted in sedimentation and mouth constriction,ultimately leading to closure of the River Murray mouth in 1981 (Bour-man and Harvey, 1983; E&WS, 1981; Harvey, 1996; Walker, 2002). Be-fore this, there had been no record of closure before or after its first surveyof 1839. While neither Flinders nor Baudin plotted the mouth of the River Mur-ray during their meeting in Encounter Bay in 1802, this is not remarkable,because they were many kilometres offshore from a low-lying shorelineand there was obviously no large discharge of freshwater and sedimentfrom the river. Previously, Flinders had also failed to plot the outlet of theBrisbane River into Moreton Bay, as well as the mouth of the ClarenceRiver in New South Wales (Figure 1), even though he had anchored off-shore from it (Fornasiero, Monteath, and West-Sooby, 2010). River flow management has had dramatic impacts on the growth of BirdIsland. River flows have been discharged mainly through the Goolwa (mostwesterly) and Tauwitchere (most easterly) barrages (Figure 2). However,the barrage on Mundoo Channel, which offers the most direct avenue tothe sea and originally evacuated approximately 10% of the total flow of theRiver Murray (Oliver and Anderson, c. 1940), was seldom used due to thecumbersome nature of its operation. The Mundoo barrage occupies lessthan one-third of the width of the channel, while the remainder comprisesa causeway, resulting in significant sediment accumulation both upstreamand downstream of the barrage. Six gates of the Mundoo barrage have nowbeen modified for easy operation, but the impact of this modification,after 70 years of restricted flow and sediment constriction, is likely to beminor. Before river regulation, flows through an active Mundoo Channelhelped to disperse the sand plumes of the flood tidal deltaic sediments andinhibited vegetation growth. After regulation, sand plumes of the floodtidal delta were protected both from river and ebb tidal flows by the Mun-doo barrage and were later protected from sea waves by the prolongationIssue 8, August 2014 Continued on Next Page 49

Previous Page Table of C Flood Tidal Deltaic Island iof Younghusband Peninsula to the NW. The setting had been establishedfor the growth of a permanent, vegetated sand island at the outlet of Aus-tralia’s largest exoreic river system. Figure 3. Aerial photography from 2001 showing the major dune, salt marsh, and sand flat features of Bird Island, together with the extensive plumes of flood tidal sediments trailing to its SW. Ongoing sedimenta- tion required dredging to prevent total inlet closure (Mapland, Depart- ment for Environment and Heritage, South Australia). Width of field is about 3.25 km.50 Just Cerfing Vol. 5, I