UNIVERSITY OF GHANA COLLEGE OF BASIC AND APPLIED SCIENCES INSTITUTE FOR ENVIRONMENT AND SANITATION STUDIES (IESS) ASSESSING THE ECOLOGICAL CHARACTER OF WETLANDS AND THEIR IMPACT ON THE DISTRIBUTION AND ABUNDANCE OF WATERBIRDS IN SOME COASTAL WETLANDS IN GHANA This thesis is submitted to the University of Ghana, Legon BY STEPHEN ADDO ODURO (ID 10289891) IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE AWARD OF PHD IN ENVIRONMENTAL SCIENCE DEGREE DECEMBER, 2022 University of Ghana http://ugspace.ug.edu.gh I I …………………… DECLARATION This thesis is the result of research by Stephen Addo Oduro of the Institute for Environment and Sanitation Studies (IESS), College of Basic and Applied Sciences, University of Ghana, Legon under the supervision of Prof. Chris Gordon (Institute for Environment and Sanitation Studies, IESS), Prof. Yaa Ntiamoa-Baidu ( Department of Animal Biology and Conservation Science, DABCS) , Dr. Daniel Nukpezah (Institute for Environment and Sanitation Studies, IESS) and Dr. Benjamin Nyarko ( Department of Geography and Regional Planning , University of Cape Coast) and the literature cited in the thesis duly acknowledged. Sign …….. Date 30 th December, 2022 Stephen Addo Oduro (10289891) CANDIDATE Sign ………… Date: 30 th December, 2022 Prof. Chris Gordon (Principal Supervisor) Sign ……………………………. Date: 30 th December, 2022 Prof. Yaa Ntiamoa-Baidu (Supervisor) Sign … Date: 30 th December, 2022 Dr. Daniel Nukpezah (Supervisor) Sign … ……... Date : 30 th December, 2022 Dr. Benjamin Nyarko (Supervisor) University of Ghana http://ugspace.ug.edu.gh II I ABSTRACT This study sought to assess the ecological character of the Sakumo II, Laloi and Kpeshie coastal wetlands in Ghana as these wetlands face massive degradation largely driven by urbanization and the rapidly growing human population in these areas. Specifically, the study investigated the quality of water and sediments, the changes in the physical characteristics (land use/land cover), the distribution of benthic macroinvertebrates, the growth and condition factor of the predominant fish species in lagoons in Ghana (Sarotherodon melanotheron), and how they influence the abundance and distribution of waterbirds on these wetlands. Data for this study were obtained from direct field observation and laboratory analysis. Counting of waterbirds was done by using a Swarovski 20 x 60 telescope while sampling and laboratory analysis of water and sediment were done by using approved standard methods (APHA, 2005). The sampling and sorting of benthic macroinvertebrates into their various taxa were also done by appropriate keys and guides. The standard length and weight of the blackchin tilapia (Sarotherodon melanotheron) were measured using the rule and Mettler Toledo Weighing balance while Landsat thematic images were freely downloaded from the United States Geological Survey (USGS) for the years 1986, 2002, and 2017. A total of 24,247 individual waterbirds belonging to 13 families were counted monthly on all three wetlands over a period of one year. Fifty (50) different waterbird species were recorded with the most abundant species belonging to the family Scolopacidae (88.71%) which were mostly waders. In terms of abundance of waterbirds on each site, 12,143 individual waterbirds representing 50.1% of total count was recorded on the Laloi wetland with the Common Ring Plover (Charidrius hiatucula) being the dominant species. The Sakumo II had a record of 10,116 waterbirds representing 41.7% with the Collared Pranticole (Glareola prantincola) as the most dominant. The Kpeshie wetland recorded 1,988 representing 8.2% of the total count with the Common Sandpiper (Actitis hypoleucos) as the most abundant waterbird. In terms of land use land cover changes (LULC) on the wetlands, there was a decrease change of 57.3% of the vegetative cover and 0.6% of waterbodies between 1986 and 2017 with a corresponding increase of built-up areas by 54.4% on the Sakumo II wetland. Vegetative cover and waterbodies also decreased by 58.3% and 6.6% on the Laloi wetland with a resultant increase of 53% in built–up areas over the same period. Furthermore, the vegetative cover and waterbodies University of Ghana http://ugspace.ug.edu.gh III I decreased by 33.7% and 15.2% on the Kpeshie wetland while built-up increased significantly by 50.8%.There were significant positive correlation between conductivity and nitrite (r=0.698, r=0.760, p<0.01 respectively) likewise an inverse relationship between water depth, phosphate and nitrate (r=-0.998, r=-0.920, r=-0.981; p<0.01 respectively) and built-up on the Sakumo II wetland. Land use land cover variables together accounted for 26.8% of the changes in abundance of waterbirds during the study. Built-up and vegetation had a significantly negative relationship with waterbirds abundance [β=-0.651; p<0.05] [β=-1.185; p<0.05] while waterbodies and barelands had a significantly positively relationship with waterbird abundance [β=0.487; p<0.05] [β=1.430; p<0.05]. The mean pH(7.65 ±0.65, 8.05 ±0.65, 7.92±1.30) and temperature (29.23 ±1.35oC, 28.76 ± 0.74oC and 29.71 ±2.11oC) of water samples collected from the Sakumo II, Laloi and Kpeshie wetlands respectively were typical of shallow coastal waters in Ghana with ambient pH and temperatures within a narrow range of 6 - 9 and 25-35 0C. The BOD, turbidity, phosphate and nitrate levels in water samples on both the Sakumo II and Kpeshie wetland were above the WHO permissible limits. Based on the pollution load index (PLI) estimated for all the wetlands using the bottom sediment, there was no overall pollution of heavy metals in sediment although some sites showed extreme enrichment (PLI<1). Heavy metals in PC1, PC2 and PC3 jointly and significantly contributed 25%, 57% and 30% respectively to macroinvertebrates abundance at the Sakumo II, Laloi and Kpeshie wetlands [R 2 =0.25 p<0.05; R 2 =0.57, p<0.05; R 2 =0.30, p<0.05]. A total of 4,474 macroinvertebrates individuals belonging to three major phyla (Annelida, Mollusca and Crustacean) were recorded during the study. Hydrobia spp, Cerithedia spp and the Nereis spp were the most abundant on the Sakumo II, Laloi and Kpeshie wetlands respectively. Macroinvertebrates abundance contributed 12%, 22% and 4% to waterbirds abundance at Sakumo II, Laloi and Kpeshie wetlands respectively [R 2 =0.12, p>0.05; R 2 =0.22, p<0.05; R 2 =0.04, p>0.05]. Sarotherodon melanotheron fishes in the Sakumo II lagoon exhibited isometric growth (‗b‘ is nearer to 3) while a negative allometric growth pattern was observed in fishes from the Laloi and Kpeshie lagoons. Mean condition factors estimated for Sarotherodon melanotheron on all wetlands were greater than one (1) indicating a good environment for fish survival and abundance. Fish condition factor also significantly contributed to 25%, 34% and 35% of waterbirds abundance on the Sakumo II, Laloi and Kpeshie wetlands respectively [R 2 =0.25 p<0.05; R 2 =0.34, p<0.05; R 2 =0.39, p<0.05]. University of Ghana http://ugspace.ug.edu.gh IV I There have been major changes in the quality of water and sediment on all three wetlands, likewise, significant changes in the vegetative cover, waterbodies and built-up areas between 1986 and 2017 due to human interferences on the wetlands. The unprotected Laloi wetland, however, supported the highest number of waterbirds compared to the protected Sakumo II wetland during the study. Major stakeholders like the EPA, the Water Resources Commission, the Forestry Commission, the Ghana Wildlife Division as well as the District and Municipal Assemblies should enforce all existing laws that will help conserve and protect these wetlands from further deterioration. Education and awareness creation on the level of usage, importance and benefits derived from these urban coastal wetlands should be intensified within the catchment areas as human population continues to increase inorder to achieve Goal 6, 14 and 15 of the Sustainable Development Goals (SDG) in and around these urban wetlands. University of Ghana http://ugspace.ug.edu.gh V I DEDICATION This thesis is dedicated to my wife, Rhoda Okwan Afful and my future leaders Nana Yaw Safo, Okatakyie Kofi Safo and Opanyin Yaw Safo for their love, prayers, understanding and unflinching support during my studies. University of Ghana http://ugspace.ug.edu.gh VI I ACKNOWLEDGEMENTS I am very grateful to the Almighty God for his blessings and strength throughout the period of my studies and to Apostle Dr. Kwadwo Safo (Founder, Kristo Asafo Mission of Ghana), Nana Kwadwo Safo Akofena (Leader, Kristo Asafo Mission of Ghana) for their prayers, guidance and financial support throughout my education. I wish to express my invaluable appreciation to my supervisors Prof. Chris Gordon, Prof Yaa Ntiamoa-Baidu, Dr. Daniel Nukpezah and Dr. Benjamin Nyarko for their instructions, directives, concerns and constructive criticism without which this academic journey would have been endless. My sincere appreciation goes to Mr. Joshua Lartey (Asheshi University), Mr. Nash (Chief Technician, Inorganic Laboratory) and the staff of the Chemistry Department of the Ghana Atomic Energy Commission (GAEC), Mr. Ansah and the staff of Ecolab, University of Ghana, Mr. Ali Nuoh, Dr. Jones Kpakpa Quartey and staff of the Centre for African Wetlands (CAW), University of Ghana. I gracefully acknowledge the immense financial support received from the University of Ghana BANGA- Africa Scholarship. Finally, my sincere thanks go to my mother Obaapanyin Akua Darkoah and siblings my friends, Akua Akyea Frimpong, Dr. Kofi Asare Nhyira, Dr. Nana Kofi Safo, Dr. Nana Opoku, Dr. Yaw Owiredu Mantey, Akwasi Ofori, Mawusi Adepa Mawuli, Diana Ewusi, Yaw Agbale, Nana Kwaku Afriyie and wife Maa Esi Techie-Mensah, Akosua Adu-Poku, Kofi Safo (FC-KAMOG), my childhood friend Lawyer Ellery Kye Addo, Pastor Kwadwo Intseful, Lawyer Festus Owusu Badu, Mr Augustus Aggor (Former Lecturer, University of Ghana, now deceased) for their unfailing support, encouragement throughout the writing of this thesis. May the Almighty God bless you all. University of Ghana http://ugspace.ug.edu.gh VII I TABLE OF CONTENTS DECLARATION…………………………………………………………………………………... I ABSTRACT………………………………………………………………………………………. II DEDICATION…………………………………………………………………………………. … V ACKNOWLEDGEMENT………………………………………………………………………...VI TABLE OF CONTENTS……………………………………………………………………….. VII LIST OF FIGURES/MAPS…………………………………………………………………….. XIV LIST OF TABLES………………………………………………………………………………. XV LIST OF PLATES……………………………………………………………………………… XVII LIST OF ABBREVIATIONS………………………………………………………………….. XIX CHAPTER ONE………………………………………………………………………………. . 1 Introduction…………………………………………………………………………………….. 1 1.1 Problem statement and relevance of the study…………………………………………. 3 1.2 Objectives……………………………………………………………………………… 7 1.3 Research Questions……………………………………………………………………. 8 1.4 Hypotheses…………………………………………………………………………….. 8 CHAPTER TWO………………………………………………………………………………. 9 2.0 Literature review………………………………………………………………………. 9 2.1 Global overview of wetlands…………………………………………………………. 9 2.1.1 Importance and threats to wetlands…………………………………………………. 10 2.1.2 Global effort to protect wetlands………………………………………………………. 11 2.2 Wetlands in Ghana…………………………………………………………………….. 13 2.3 Waterbirds……………………………………………………………………………… 14 2.3.1 Waterbird distribution and abundance on wetlands in Ghana…………………………. 15 2.4 Water quality of coastal wetlands……………………………………………………… 16 2.4.1 Impact of water quality on waterbird distribution……………………………………… 17 University of Ghana http://ugspace.ug.edu.gh VIII I 2.5 Sediment quality of coastal wetlands…………………………………………………… 18 2.5.1 Impact of sediment quality on macroinvertebrates and waterbird distribution…….. 19 2.6 Benthic macroinvertebrates……………………………………………………… 20 2.6.1 Macroinvertebrate abundance and its impact on waterbird distribution…………… 21 2.7 Fishery resource in coastal wetlands in Ghana……………………………………… 22 2.7.1 Condition of fish as an indicator of waterbird distribution…………………………. 24 2.8 Land use land cover changes (LULCC) on wetlands……………………………….. 25 2.8.1 Effect of LULC changes on biodiversity and waterbirds……………………………. 26 2.9 Conceptual frame work for the study………………………………………………… 26 CHAPTER THREE………………………………………………………………………….. 29 Methodology………………………………………………………………………………… 29 3.1 Study areas…………………………………………………………………………… 29 3.1.1 Sakumo Ramsar Site…………………………………………………………. 29 3.1.1.1 Location……………………………………………………………………… 29 3.1.1.2 Population…………………………………………………………………….. 30 3.1.1.3 Vegetation……………………………………………………………………. 30 3.1.1.4 Fauna………………………………………………………………………….. 30 3.1.1.5 Land Use……………………………………………………………………… 31 3.1.2 Laloi coastal wetlands………………………………………………………… 32 3.1.2.1 Location……………………………………………………………………….. 32 3.1.2.2 Population…………………………………………………………………….. 32 3.1.2.3 Vegetation……………………………………………………………………. 33 3.1.2.4 Fauna………………………………………………………………………… 33 3.1.2.5 Land Use……………………………………………………………………… 33 3.1.3 Kpeshie Coastal Wetland……………………………………………………... 34 3.1.3.1 Location………………………………………………………………………. 34 3.1.3.2 Population…………………………………………………………………….. 35 3.1.3.3 Vegetation……………………………………………………………………… 35 3.1.3.4 Fauna…………………………………………………………………………… 36 3.1.3.5 Land use………………………………………………………………………… 36 3.2 Study design and data collection……………………………………………………….. 38 3.2.1 Sampling Points………………………………………………………………… 38 University of Ghana http://ugspace.ug.edu.gh IX I 3.2.1.1 Description of sampling points…………………………………………………. 38 3.2.1.2 Sampling site and sample locations……………………………………………. 42 3.2.2 Land use land cover data acquisition and image preprocessing………………….. 43 3.2.2.1 Land use/Land cover (LULC) Classification: Supervised………………………. 44 3.2.2.2 Accuracy assessment………………………………………………………….. 46 3.2.2.3 Sampling and collection of water samples……………………………............. 47 3.2.2.3.1 Sample containers and sampling of water …………………………………… 47 3.2.2.3.2 Glasswares, equipments, chemicals and reagents……………………………. 48 3.2.2.3.3 Preparation of Solutions……………………………………………………… 48 3.2.2.3.4 Laboratory analyses of water samples……………………………………….. 49 3.2.2.3.5 Nutrients in water samples …………………………………………………….. 53 3.2.2.3.6 Digestion and analysis of water samples……………………………………… 54 3.2.2.3.7 Quality control measures……………………………………………………… 55 3.2.2.4 Sediment sampling…………………………………………………………… 56 3.2.2.4.1 Laboratory analysis…………………………………………………………… 56 3.2.2.4.2 Calculation of concentration of AAS readings ………………………………. 56 3.2.2.4.3 Statistical analysis of water and sedimemt data………………………………. 57 3.2.2.4.4 Pollution Indices using the Sediments………………………………………… 58 3.2.2.5 Avifauna data collection………………………………………………………. 59 3.2.2.5.1 Statistical analysis of avifaunal data………………………………………….. 60 3.2.2.6 Collection of benthic macrofauna…………………………………………….. 61 3.2.2.6.1 Laboratory processing of benthic macrofauna………………………………… 62 3.2.2.7 Sampling and collection of fishery data………………………………………... 62 3.2.2.7.1 Statistical analysis of fishery data……………………………………………… 63 3.2.2.8 Socioeconomic survey…………………………………………………………. 64 3.2.2.8.1 Hypothesis……………………………………………………………………… 65 3.2.2.9 Data screening and examination ………………………………………………. 65 3.2.2.9.1 Analysis of Missing Values…………………………………………………… 65 3.2.2.9.2 Investigation of Outliers………………………………………………………. 66 3.2.2.9.3 Data normality test…………………………………………………………….. 66 3.2.2.9.4 Multicollinearity test…………………………………………………………… 66 University of Ghana http://ugspace.ug.edu.gh X I CHAPTER FOUR………………………………………………………………………………... 67 RESULTS………………………………………………………………………………............... 67 4.1 Accuracy assessment and land use /land cover changes (LULC) on the wetlands……………………………………………………………………. 67 4.1.1 Land use/land cover matrix of the wetlands……………………………….. …… 68 4.2 Water quality of the Sakumo II, Laloi and Kpeshie coastal wetlands……………... …… 76 4.2.1 Physicochemical parameter…………………………………………………….. 76 4.2.2 Cations, anions and nutrients in water samples from coastal lagoons………….. 78 4.2.3 Concentration of heavy metals in lagoon waters on wetlands………………….. 80 4.2.4 Comparing current state of wetland water quality to baseline and other studies………………………………………………………………… 92 4.2.5 Correlation between LULC changes and water quality parameters……………. 94 4.3 Concentration of heavy metals in bottom sediment in study areas………………… …… 100 4.3.1 Principal Component Analysis and Correlation Matrix…………………… …… 102 4.3.2 Degree of contamination in lagoon sediments………………………………… 107 4.3.2.1 Enrichment Factor…………………………………………………………….. 107 4.3.2.2 Contamination factor (CF)…………………………………………………….. 108 4.3.2.3 Pollution Load Index (PLI)…………………………………………………….. 109 4.3.2.4 Geo-accumulation Index (Igeo)………………………………………………… 110 4.4 Macroinvertebrate assemblage of the coastal wetlands ………………………………… 111 4.4.1 Spatio-temporal variation in the abundance of macroinvertebrates on wetlands………………………………………………………………………. 115 4.4.2 Diversity indices of macroinvertebrates on the wetlands…………………. ……. 117 4.4.3 Relating macroinvertebrates distribution to water quality on wetlands…………. 118 4.4.4 Sediments predictors of macroinvertebrates…………………………………….. 120 4.5 Distribution of waterbirds within the Sakumo II, Laloi and Kpeshie wetlands…………... 122 4.5.1 Waterbird abundance among the site……………………………………………. 125 4.5.2 Spatio temporal distribution of waterbirds on the wetland……………………… 126 4.5.3 Diversity indices of waterbirds on wetlands……………………………………. 127 4.5.4 Similarity indices of waterbird on the wetland sites…………………………….. 128 4.5.5 Linear regression of macroinvertebrates predictors of waterbirds on University of Ghana http://ugspace.ug.edu.gh XI I wetlands……………………………………………................................... …….. 129 4.5.6 Linear regression between water quality and waterbirds on wetlands………….. 129 4.5.7 Relationship between land use land cover and waterbirds abundance………….. 131 4.6 Length-weight relationship of Black Chin Tilapia (Sarotherodon melanotheron)………. 132 4.6.1 Monthly length-weight relationship of Sarotherodon melanotheron ……………. 133 4.6.2 Condition factor of the black-chin tilapia (Sarotherodon melanotheron) on wetlands……………………………………………………………………………… 135 4.6.3 Multiple linear regressions between water quality and fish condition …............. 136 4.7 Socio-Economic Survey…………………………………………………………………. 138 4.7.1 Profile of respondents……………………………………………………………. 138 4.7.1.1 Educational level of respondents……………………………………………… 139 4.7.1.2 Main occupation of respondents………………………………………………… 140 4.7.1.3 Benefits derived from the wetlands……………………………………………… 141 4.7.1. 4 Respondents knowledge about the importance and changes on the wetland……. 142 4.7.1.5 Drivers of the changes on the coastal wetlands by respondents………………….. 144 4.7.1.6 Level of usage and the changes in the wetlands by respondents…………………. 145 4.7.1.7 Management practices to sustainably protect wetlands………………………… 146 CHAPTER FIVE………………………………………………………………………………… 150 DISCUSSION………………………………………………………………………………….. 150 5.1 Land Use/Land cover changes on wetlands…………………………………………….. 150 5.2 Water and sediments quality and their impact on biological diversity………………… . 154 5.2.1 Changes in water quality parameters on wetlands……………………………… 154 5.2.1.1 Physicochemical parameters……………………………………………………. 154 5.2.1.2 Nutrients in coastal lagoons……………………………………………………… 157 5.2.1.3 Trace and heavy metals in coastal lagoons……………………………………… 159 5.2.1.4 Correlation between physicochemical, nutrients, heavy metals in water and macroinvertebrates abundance……………………………………………… 162 5.3 Changes in sediment quality on wetlands…………………………………………….. 166 5.3.1 Assessment of heavy metal contamination in sediments………………………. 170 5.3.2 Correlation between sediment quality and macroinvertebrates………………... 173 5.4 Macroinvertebrates distribution and abundance on wetlands…………………………… 175 University of Ghana http://ugspace.ug.edu.gh XII I 5.4.1 Macroinvertebrates as predictors of waterbirds on wetlands…………………… 177 5.5 Waterbird distribution and abundance on coastal wetlands……………………………... 178 5.5.1 Changes in waterbird populations……………………………………………… 178 5.5.2 Relationship between LULC variables and waterbirds……………….………….. 181 5.6 Growth parameter of S. melanotheron………………………………………………………… 182 5.6.1 Length-weight relationship (LWR)………………………………………………. 182 5.6.2 Condition factor of Sarotherodon melanotheron…………………..………………… 184 5.6.2.1 Relationship between water quality, fish condition and waterbirds ...…… ...… 185 5.7 Human interactions with the coastal wetlands……………………………………….. 187 5.7.1 Perception of respondent towards changes in the wetlands…………………….. 189 5.7.2 Management strategies to conserve coastal wetlands……………….…………... 189 CHAPTER SIX………………………………………………………………………………. 191 Conclusion and recommendations………………………………………………………………. 191 6.1 Conclusion………………………………………………………………………………….. 191 6.2 Recommendation……………………………………………………………………………. 197 REFERENCES………………………………………………………………………………….. 199 Appendices……………………………………………………………………………………… 236 Appendix I-1: Total individual waterbird count on the Sakumo, Laloi and Kpeshie wetlands……………………………………………………………………………… 236 Appendix I-2: Total individual monthly count of waterbirds on the Sakumo II wetland……… 239 Appendix I-3: Total individual monthly count of waterbirds on the Laloi wetland…………… 241 Appendix I-4: Total individual monthly count of waterbirds on the Kpeshie wetland………… 244 Appendix I.5: Total abundance and distribution of macroinvertebrates ……………………….. 246 Appendix I.6 Monthly abundance and distribution of macroinvertebrate at Sakumo II lagoon………………………………………………………………. 247 Appendix I-7: Monthly abundance and distribution of macroinvertebrate at Laloi lagoon……………………………………………………………......... 248 Appendix I-8: Monthly abundance and distribution of macroinvertebrate at Kpeshie lagoon………………………………………………………………... 249 Appendix 1-9: A summary of the independent t test showing differences in water quality elements by year…………………………………………………. 250 University of Ghana http://ugspace.ug.edu.gh XIII I Appendix 1-10: A summary of the ANOVA analysis showing differences in water quality elements by sites …………………………………………………… 251 Appendix I.11: Equation parameters of length-weight for Sarotherodon melanotheron from the Sakumo II lagoon………………………………………………… 253 Appendix I.12: Equation parameters of length weight for Sarotherodon melanotheron from the Laloi lagoon……………………………………………………..... 254 Appendix I.13: Equation parameters of length-weight for Sarotherodon melanotheron from the Kpeshie lagoon…………………………………………………..... 255 Appendix I-14: Sediment quality guideline (SQG) values……………………………........ 256 Appendix I-15: Questionnaire on the changes in the coastal wetlands, its usage, associated problems and measures to conserve /protect the wetlands……….. 257 Appendix I-16: Pollution Indices (Geo-accumulation Index, Contamination factor and Enrichment factors) Muller‘s classification for geo-accumulation index (Igeo).. 262 University of Ghana http://ugspace.ug.edu.gh XIV I LIST OF FIGURES/MAPS Figure Description Page 2.1 Conceptual framework showing linkages between ecosystem variables and waterbirds 27 3.1 Google Earth Map of the Sakumo Ramsar site (2018) 30 3.2 Google earth map of the Laloi coastal wetland (2018) 32 3.3 Google Earth Map of Kpeshie wetland (2018) 35 3.4 Map of Sakumo coastal wetland showing sampling point 39 3.5 Map of the Laloi coastal wetland showing all the sampling points 40 3.6 Map of Kpeshie coastal wetland showing sampling points 41 4.1 Land use/land cover maps for the Sakumo wetland derived from satellite data for 1986, 2002 and 2017 69 4.2 Land use/land cover maps for the Laloi wetland derived from satellite data for 1986, 2002 and 2017 70 4.3 Land use/land cover maps for the Laloi wetland derived from satellite data for 1986, 2002 and 2017 71 4.4 Changes in land cover type on the Sakumo II wetland 73 4.5 Changes in land cover type on the Laloi wetland 73 4.6 Changes in land cover type on the Kpeshie wetland 74 4.7 Monthly total count of macroinvertebrates on the wetlands 116 4.8 Monthly distribution of waterbird count on the wetlands 126 4.9 Bray Curtis Similarity index of study sites based on waterbird abundance 128 4.10 Monthly growth of black chin tilapia on the wetlands 134 4.11 Mean condition factor (K) recorded for the study 135 4.12 Educational level of respondent 140 4.13 Main occupation of respondents 141 4.14 Benefits derived from wetlands by respondents 142 4.15 Contribution of human activities on LULC changes on wetlands 144 University of Ghana http://ugspace.ug.edu.gh XV I LIST OF TABLES Table Description Page 3.1 GPS points of sampling sites 42 3.2 Details of satellite data used in the study 43 3.3 Description of land use/land cover unit 45 4.1 Summary of land use/land cover classification for Sakumo II for the years 1986, 2002 and 2017. 67 4.2 Summary of land use/land cover classification for Laloi for the years 1986, 2002 and 2017. 68 4.3 Summary of land use/land cover classification for Kpeshie for the years 1986, 2002 and 2017. 68 4.4 Land use/land cover size/changes within the Sakumo II, Laloi and Kpeshie wetlands 72 4.5 Statistical summary of physicochemical results of surface water in the Sakumo II, Laloi and Kpeshie lagoons 76 4.6 Cations, anions and nutrients on the wetlands sites 79 4.7 Mean concentration of heavy metals in surface water (mg/l) on wetlands 81 4.8 Summary of the intercorrelation matrix showing the relationship between water quality elements 83 4.9 Summary of the PCA for water quality showing eigenvalues and variances 85 4.10 Summary of the principal component analysis for water quality showing the factor loadings 88 4.11 Post hoc analysis showing differences in physicochemical water quality parameters by sites 89 4.12 Post-hoc analysis showing differences in cation and nutrient quality elements by sites 90 4.13 Post-hoc analysis showing differences in heavy metal elements by sites 91 4.14 Changes in some water quality parameters compared to baseline studies and other studies on the selected wetlands 93 University of Ghana http://ugspace.ug.edu.gh XVI I 4.15 A summary of the intercorrelation matrix showing the relationship between water quality elements and LULC elements at Sakumo II 95 4.16 A summary of the intercorrelation matrix showing the relationship between water quality elements and LULC elements at Laloi 97 4.17 A summary of the intercorrelation matrix showing the relationship between water quality elements and LULC elements at Kpeshie 99 4.18 Descriptive statistics on the concentration values of heavy metals (mg/kg) in sediments on the wetland sites 101 4.19 Pearson‘s correlation coefficient of heavy metals in Sakumo II lagoon sediments 102 4.20 Pearson‘s correlation coefficient of heavy metals in Laloi lagoon sediments 102 4.21 Pearson‘s correlation coefficient of heavy metals in Kpeshie lagoon sediments 103 4.22 Summary of the PCA showing eigenvalues and variances explained for sediments on wetlands 105 4.23 PCA showing factor loadings for sediments on wetlands 106 4.24 Enrichment Factor (EF) values of heavy metals in Sakumo II, Laloi and Kpeshie lagoon sediments 108 4.25 Contamination factor (CF) for heavy metals of the Sakumo II, Laloi and Kpeshie lagoon sediments 109 4.26 Geo-accumulation indices (Igeo) of heavy metals in Sakumo II, Laloi and Kpeshie lagoon sediments 110 4.27 Distribution and abundance of macroinvertebrates during the study 112 4.28 ANOVA test showing differences in macroinvertebrates abundance by sites 114 4.29 Multiple regression showing differences in the abundance of macroinvertebrates by sites 114 4.30 Species diversity, richness, and evenness for macroinvertebrates on the wetlands 117 University of Ghana http://ugspace.ug.edu.gh XVII I 4.31 Multiple linear regression showing water quality predictors of macroinvertebrates 119 4.32 Multiple linear regressions showing the sediment predictors of macroinvertebrates 121 4.33 Relative abundance of waterbirds counted during the survey 122 4.34 One-way ANOVA test showing differences in waterbirds abundance by sites 125 4.35 Multiple comparison showing differences in waterbirds abundance by sites 125 4.36 Diversity indices of waterbirds on wetlands 127 4.37 Multiple linear regression showing macroinvertebrates predictors of waterbirds 129 4.38 Multiple regression showing the water quality elements as predictors of waterbird abundance 130 4.39 Relationship between landuse/landcover variables and waterbirds abundance 131 4.40 Length-weight relationship parameters of S. melanotheron from study sites 133 4.41 Multiple linear regression showing water quality predictors of fish condition 137 4.42 Regression analysis showing fish condition as a predictor of waterbird abundance 137 4.43 Respondents‘ background information 139 4.44 A cross tabulation showing the relationship between importance of wetlands and changes in the wetlands. 143 4.45 A cross tabulation showing the relationship between level of usage and changes in the wetlands 145 4.46 Respondents opinion about the management and conservation practices to protect the wetlands 146 4.47 Relationship between importance of wetlands and appropriate methods of conserving the wetlands 148 University of Ghana http://ugspace.ug.edu.gh XVIII LIST OF PLATES Plate Description Page 3.1 Fish species caught from the Laloi lagoon during the study by a fisher…………… 34 3.2 Relatively dense vegetative cover around the Kpeshie lagoon…………………… 36 3.3 Land use within the Kpeshie lagoon and its catchment…………………………… 37 University of Ghana http://ugspace.ug.edu.gh XIX LIST OF ABBREVIATIONS AAS Atomic Absorption Spectrometer APHA American Public Health Association ASCR Automatic Scattergram-Controlled Regression ATSDR Agency for Toxic Substances and Disease Registry BOD Biochemical Oxygen Demand CF Contamination Factor CCME Canadian Council of Ministers of the Environments COP Conference of Parties CWMP Coastal wetland management project EF Enrichment Factor EPA Environmental Protection Agency FAAS Flame atomic absorption spectrometry DO Dissolved Oxygen GPHC Ghana Population and Housing Census GPS Global Positioning System GSS Ghana Statistical Service DWAF Department of Water Affairs and Forestry IUCN International Union for Conservation of Nature University of Ghana http://ugspace.ug.edu.gh XX LULC Land use/Land cover LULCC Land use/Land cover changes LWR Length-Weight Relationship MCL Maximum Contaminant Level PCA Principal Component Analysis PLI Pollution Load Index SQG Sediment Quality Guidelines SSBP-G Save the Seashore Birds Project-Ghana TMA Tema Municipal Assembly UNEP United Nations Environment Programme USGS United States Geological Survey WHO World Health Organisation WRC Water Research Commission University of Ghana http://ugspace.ug.edu.gh 1 CHAPTER ONE INTRODUCTION 1.0 Background Wetland ecosystems are essential for the wellbeing of humans and contribute to local and national economies (EPA, 2017). Globally, wetlands are the most dynamic ecosystem on the surface of the earth due to the diversity of the habitat which comprises key fauna and flora they support. Wetlands are generally characterised by shallow waters, covering waterlogged soil, interspersed by submerged and emergent vegetation which supports significant biodiversity throughout the world (Huang et al., 2012, Zhang et al., 2013, Mitsch & Gosselink, 2015). Wetlands purify and replenish waters, provide fish and foodstuff that feed humankind, act as natural sponges against flooding and drought and protect coastlines as well as help fight climate change (Convention on Biological Diversity, 2015).Wetlands also serve as key habitats of the world‘s waterbirds; as migratory waterbirds make use of wetlands along their flyways either for staging (stopover), nesting, breeding, roosting, foraging and for the non- breeding periods (Stewart, 2001; Convention on Biological Diversity, 2015). The Ramsar convention recognizes five main types of wetlands which include marine, estuarine, lacustrine; riverine and palustrine wetlands (Ramsar Convention Secretariat, 2016) and defines their ecological character as the structure and inter-relationships between the physical, biological, and chemical components of the wetlands which are derived from the interactions among the processes, functions, and values of the wetland ecosystem (Ramsar, 2016). University of Ghana http://ugspace.ug.edu.gh 2 Ghana is a signatory to several international conventions such as the Ramsar Convention and the Bonn Convention that seek to conserve and protect wetlands and the biodiversity they support. Under these treaties and conventions, Ghana has an obligation to ensure the wise use of all wetlands in the country for the benefit of its human population, wetland habitats, wildlife, and migratory animals in a sustainable manner without compromising the natural properties of the ecosystem (Ntiamoa-Baidu, 1991, Ntiamoa-Baidu & Gordon, 1991). The Bonn convention for example obliges Ghana to specifically provide stringent protection for migratory species (Ntiamoa-Baidu & Gordon, 1991). Ghana‘s 550 km coast has about one hundred (100) wetlands comprising mainly of non- tidal estuaries and lagoons (Ntiamoa-Baidu, 1991, Ryan, 2005). In 1992, Ghana designated five coastal wetlands as Ramsar sites based on their international significance for waterbirds in terms its population and species present in globally significant numbers (Ntiamoa-Baidu & Herpburn, 1988; Ntiamoa-Baidu, 1991; Willoughby et al., 2001). Gordon et al., (1998) also reported of a number of non-protected wetlands in Ghana, which also supported many forms of biodiversity, including waterbirds. Attuquayefio and Gbogbo (2001) indicated that most of these non-protected wetlands in Ghana were publicly owned, unmanaged, unregulated and were being exposed to indiscriminate exploitation of the resources they provided. Rapid population growth with associated anthropogenic interferences depletes wetland resources and reduces the ecosystem services they provide. The upsurge of these human pressures and the inefficient land-use management policies in Ghana has significantly affected wetland ecosystems especially urban coastal wetlands (Pinamang, 2001, Attuquayefio & Gbogbo, 2001). With the intensification of human activities, wetlands in general have been subjected to heavy human pressure through encroachment and unsustainable exploitation of the wetland University of Ghana http://ugspace.ug.edu.gh 3 resources through agricultural activities leading to runoff, and siltation, likewise an increase in levels of industrial and domestic pollutants (Baral & Inskipp, 2005, Kafle et al., 2008, Mitsch & Gossenlink, 2015). These threats on wetlands have severe consequences on biodiversity especially the waterbird species as it leads to changes in their community structure as well as a decline in their numbers and population (Millennium Ecosystem Assessment, 2005, Kloskowski et al., 2009). The survival and reproductive success of migratory waterbirds are determined mainly by the quality of the wetlands they encounter on their migratory route (Spellman, 2004) as the distribution, abundance and population dynamics of waterbird provide important ecological information which reflects the quality of wetlands. The diversity and population of waterbird species in an ecosystem is often a good indicator of the status of the ecosystem as waterbirds serve as key bioindicators of wetland quality (Schreiber & Burger, 2002, Abdourahamane, 2010). Also, the density and composition of food sources on wetlands for waterbirds serves as an important bioindicator of the quality of the wetland habitat as well (Davis & Smith, 1998; Taft & Haig, 2005; Hartke et al., 2009). Therefore, changes in the land cover and pollution of any coastal wetlands, mainly from the discharge of raw sewage, industrial waste and agricultural runoffs will also affect waterbird and the macroinvertebrates community structure and population (Tanalgo et al., 2015). Low density of macroinvertebrates on wetlands will suggest few and less food source to support waterbirds especially waders who depend on macroinvertebrates for survival (Ntiamoa-Baidu & Hepburn, 1988). 1.1 Problem statement and relevance of the study Although wetlands continue to support human survival by providing unique ecosystem services such as habitat for waterbirds, providing fish, fuel wood, and salt for domestic purposes as well as income for coastal dwellers, they face massive degradation largely driven University of Ghana http://ugspace.ug.edu.gh 4 by urbanization and rapidly growing human population in coastal areas (Hinrichsen, 1999; Nicholls, 2004, Ansa-Asare et al., 2008). Human activities such as over-hunting, over exploitation of fish, cutting of mangrove vegetation for fuel wood, farming practice, and developments within the catchment have negatively impacted wetlands in terms of change in the land cover, water and sediment quality, habitat loss, extinction and reduction of waterbirds and loss of other forms of biodiversity with the least ecosystem disturbance (Gordon et al., 1998, Mitsch, & Gosselink, 2000, Kangah-Kesse et al., 2007). According to a World Bank report, about 25% of the population of all Ghanaians who migrate into the cities generally live around and on coastal areas (EPA/World Bank, 1997) and contribute directly or indirectly to the amount of abuse of the coastal ecosystem with increase in untreated domestic waste discharged into wetlands especially in urban cities like Accra and Takoradi (Afoakwa et al., 1998). The Greater Accra region like most cities in the world has a considerable number of coastal wetlands along its coast and most of these urban coastal wetlands have become final recipient of all domestic, municipal, agricultural and industrial wastes which are usually transported by streams and drain directly unto the wetlands (Biney, 1986; Doamekpor et al., 2018). These wastes discharged carry large amounts of suspended solids and dissolved organic matter, as well as harmful metals thereby affecting the flora and fauna within these wetlands and its catchment (Nonterah et al., 2015). The discharge of these potentially harmful wastes unto the wetlands causes changes in the aquatic species, changes in the waterbird distribution and the health of the ecosystem due to their accumulative behaviour (Allen, 1995, Okocha & Adedeji, 2011, Pandey & Madhuri, 2014). Despite the immense value of these urban coastal wetlands for humans and biodiversity, they continue to be under constant threat from both natural and anthropogenic activities causing changes in the land cover and biodiversity especially waterbird populations and other wetlands resources (EPA, 2017). University of Ghana http://ugspace.ug.edu.gh 5 The Sakumo II wetland, a protected wetland, in recent years has seen several landuse changes largely influenced by human interference such as the conversion of the land for residential and agricultural purposes coupled with the emergence of enormous aquatic weeds in the lagoon catchment, resulting in reduced freshwater inflow into the wetland (Anku, 2006). The Sakumo II wetland which used to support a total of 66 waterbird species with an estimated bird population of 32,500 during the coastal wetland management project in 1992 (CWMP) revealed sharp declines in bird populations in similar studies by the Centre for African Wetlands (2017, 2019) on report on wetlands and waterbirds, count of the east atlantic flyway, Gbogbo et al, (2009) and Gbogbo & Attuquayefio, (2010). The Sakumo II wetland which used to holds about 90-100% of the total populations of Black Heron, Teal, Black- tailed Godwit, Avocet, and Ruff recorded on the Ghanaian coast has shown sharp declines of these species on the same wetland and in most cases total collapse of some waterbird species over the years (Ntiamoa-Baidu & Gordon, 1991; EPA, 2017). The decline in the waterbird population on most urban coastal wetlands in Ghana does not only affect the protected Sakumo II wetland but also the unprotected wetlands such as the Laloi and Kpeshie coastal wetlands in the Greater Accra region as there have been reports of sharp decline in waterbirds abundance on these unprotected wetlands as well, mainly due to the increased levels of anthropogenic activities and encroachment (Gbogbo et al., 2009, Koney, 2010, Lamptey & Danson, 2014, EPA, 2017). These anthropogenic activities in and around the Sakumo II, Laloi and the Kpeshie wetlands have become a key impairment to the quality of water, the sediments and the wetland biodiversity (Nonterah et al., 2015, EPA, 2017, Doamekpor et al., 2018). Though, reasons such as increased pesticide and chemical use from agricultural activities (Addo et al., 2011, Nartey et al., 2011, Doamekpor et al., 2018), improper disposal of sewage and refuse (Nukpezah, 2001, Ansah, 2008) as well as expansion in residential buildings and settlements University of Ghana http://ugspace.ug.edu.gh 6 (Nonterah et al., 2015) have been suggested, further investigation is required to understand how the impact of the quality of water and sediment, the land use and land cover changes, the distribution of macroinvertebrate, the health and condition of fish in the lagoons have affected the distribution and abundance of waterbirds over a period of three decades for better understanding of these urban coastal ecosystem. Few studies in Ghana have examined wholistically the status of waterbird distribution and abundance from the perspective of the land use/land cover changes, abundance of macroinvertebrates, growth and condition of fishes in the lagoon waters, the quality of water and sediment as studies conducted on these wetlands had focused primarily on the value of the wetlands for fish and waterbirds (Ntiamoa-Baidu, 1991; Koranteng, 1995; Gordon, 2000; Gbogbo & Attuquayefio, 2010; Ntiamoa-Baidu et al., 2014). Most studies on the waterbirds in Ghana have focused mostly on the designated wetlands at the expense of the non-designated ones like the Laloi, Kpeshie, Esiama, Mokwe, Korle which have been reported to support significant number of biodiversity especially waterbirds (Gbogbo, 2007, Gbogbo & Attuquayefio, 2010). The State of the Environment Report in 2016 by the Environmental Protection Agency (Ghana) established the fact that almost all the urban wetlands in Ghana were under enormous threats from urbanization, demand for the wetland for housing, industrial developments, subsistence agricultural farming activities on the wetlands, industrial pollution, domestic and agricultural waste pollution, over-exploitation of wetland resources have led to the degradation of these important urban wetlands (EPA, 2017). Currently, it is however unclear, what drives massive development leading to the degradation of these urban wetland ecosystem which was supposed to be regulated by legislations like the Wetland Management Regulation of 1999 (Legislative Instrument 1659), the Fisheries Regulations, 2010 (L.I. 1968), the Land Use and Spatial Planning Act, 2016 (Act 925) and Water Resources Commission, 1996 (Act 522) etc. University of Ghana http://ugspace.ug.edu.gh 7 These changes and degradation on the wetlands have negatively affected waterbird populations and other forms of biodiversity, thus providing high quality wetland for waterbirds and other forms of biodiversity through effective wetland management strategies and studies is urgently needed in wetland conservation to ameliorate these impacts (Weber & Haig 1996; Sekercioglu et al., 2004). Furthermore, the need for ecological studies on the selected coastal wetlands becomes more imperative when considered against the background of general global declines in the populations of migratory waterbirds (International Wader Study Group, 2003) and the global trends in which wetlands are being degraded which affects the survival and abundance of waterbirds in Ghana. In view of the importance of wetland sites locally and internationally, this current study sought to undertake an assessment of these urban wetlands in the capital of Ghana to understand the waterbird population trends to provide a basis for formulating policies for waterbird conservation in Ghana. Furthermore, assessing the changes that might have occurred on the Sakumo II, Laloi and Kpeshie wetlands over three decades will provide other possible further management strategies needed to enhance the sustainability of these urban wetlands by policymakers and other key stakeholders. 1.2 Objectives The general objective of this study is to assess changes in the ecological character of the Sakumo II, Laloi and Kpeshie wetlands and their present capacity to support waterbirds and other forms of biodiversity. The specific objectives are: i. to assess changes in the chemical composition of water and sediments of the selected wetlands and their impact on waterbirds ii. to investigate changes in the physical characteristics of the selected University of Ghana http://ugspace.ug.edu.gh 8 wetlands and the impact on composition and distribution of waterbirds over a period of three decades. iii. to investigate the spatio-temporal variation in the composition and distribution of waterbirds within the selected urban wetlands iv. to assess the growth pattern and condition factor of the predominant fish species in the coastal lagoons on the wetlands v. to identify the drivers for changes on the wetlands if any and the best management practices to be adopted to sustainably manage these wetlands through a survey 1.3 Research Questions 1. Have there been any changes that have occurred in terms of the land use/land cover on the wetlands? 2. What is the current state of the lagoon waters and sediment on the wetlands? 3. What is the current distribution and abundance of waterbird species and benthic macroinvertebrates on the coastal wetlands? 4. What are the major drivers of changes on the wetlands? 1.4 Hypotheses 1. There have been major changes on the Sakumo II, Laloi and Kpeshie coastal wetlands due to changes in the land use/land cover which has affected the abundance and distribution of waterbirds 2. Anthropogenic activities have an effect on the quality of water and sediments on the coastal wetlands 3. The protected wetlands support more waterbirds than unprotected wetland University of Ghana http://ugspace.ug.edu.gh 9 CHAPTER TWO LITERATURE REVIEW 2.1 Global overview of wetlands Wetlands occur everywhere on the surface of the earth. The total surface area of the earth presently covered by wetlands is exactly unknown; however, the UNEP-World Conservation Monitoring Centre has suggested an estimate of 5.7 million km 2 which is roughly about 6% of the Earth‘s landmass (Mitsch & Gosselink, 2015). The Ramsar Convention on Wetlands suggested global inland and coastal wetlands cover over 12.1 million km 2 (Ramsar, 2018). Wetlands are environments primarily controlled by water with its associated flora and fauna. They normally occur where the water table is at or near the surface of the land and includes other human-made wetlands such as wastewater treatment ponds and reservoirs (Ramsar, 2013, 2016). In Africa, wetlands cover approximately 1% of the total landmass with some important wetlands like the Zaire swamps, the Sudd in Egypt and Sudan, Lake Victoria basin, the Chad Basin, the Okavango Delta in Botswana and the floodplains of Rivers Niger and Zambezi (Agbemehia, 2014, Mitsch & Gosselink, 2015). Ghana also has a number of important wetlands which include the protected and designated Keta, Songor, Sakumo II, Densu and Muni coastal wetlands, as well as relatively smaller unmanaged and unprotected wetlands such as the Esiama, Kpeshie, Fosu, Nakwa, Mukwe coastal lagoons, Lake Bosumtwi, Black, Red and White Volta (Ntiamoa-Baidu & Gordon, 1991, Ministry of Lands and Forestry, 1999, Ryan & Ntiamoa-Baidu, 2000). University of Ghana http://ugspace.ug.edu.gh 10 2.1.1 Importance and threats to wetlands Wetlands are among the world‘s most productive habitats supporting countless plants and animals as well as regulating global carbon levels which serve as warehouse for most plant genetic material which feeds more than half of humanity (US Environmental Protection Agency, 2002, Clarkson et al., 2003, Ramsar, 2013). Wetlands provide tremendous services in the form of water quality to communities, fisheries; agriculture, forest resources, building materials, wildlife resources, herbal medicines; recreation and tourism opportunities to humankind (Dugan, 1990, Davis, 1993; 1994, Ramsar, 2013). Wetlands and humans are ultimately interdependent as they play a major role in the form of their cultural heritage which is often linked to communities‘ religious beliefs and spiritual values (Toit & Perret, 2006, Ramsar, 2013). Apart from the enormous benefit derived from wetlands, they are ecosystems with the most threatened habitats because of their attractiveness for development (Ntiamoa-Baidu & Hollis, 1988). Some of the major threats to coastal wetlands may be natural while others may be artificial. Some of the natural threats include floods, storms and naturally occurring processes that have the potential to destroy wetlands globally (Daryadel & Talaei, 2014). Soil erosion is a major natural threat to wetlands ecosystem because soil erosion leads to soil degradation and desertification which leads to the loss of soil nutrient (Yirdaw et al., 2017). Soil erosion further leads to sedimentation which kills most aquatic macro and micro invertebrates and destroys the unique habitat they need to survive (Yirdaw et al., 2017). Sediment re-suspend in the water columns as it turns cloudy and prevents penetration of sunlight making feeding difficult for aquatic animals which rely on sight to obtain their food source (Shakeri & Moore, 2010). University of Ghana http://ugspace.ug.edu.gh 11 Drought is also another major natural threat which affects wetlands as flora and fauna depend on water for their survival. Frequent drought on wetlands reduces the ability of wetlands potential to act as carbon sinks and turns the carbon into sources of atmospheric carbon especially methane which is a greenhouse gas (GHG) and has a negative effect on the environment (Tian et al., 2012). The artificial threats to wetlands include anthropogenic sources of pollution such as the release of urban and industrial wastewater discharges to wetlands which has the tendency of altering the growth of aquatic plants and reducing waterfowl abundance on wetlands (Daryade & Talaei, 2014). Ecotourism which plays a significant role in most economies damages wetland and protected areas as they cause serious damages to wildlife and biodiversity through tourism-related activities like constructions of roads, use of water, treatment of wastewater, and rapid urbanisation in and around wetland communities (Kotios et al., 2009). 2.1.2 Global effort to protect wetlands The interest to protect wetlands internationally increased in the 1970‘s following concerns at the frightening rate with which wetlands in Europe were being destroyed, with a resulting decline in a large number of waterfowl (Ramsar, 2013). To improve the increasing trend in wetlands destruction, the International Convention on Wetlands (Ramsar Convention), especially as Waterfowl Habitat was signed in Ramsar, Iran in 1971. At the centre and core mission of the Ramsar convention is the "wise use" concept which is primarily defined as "the maintenance of the ecological character of all wetlands achieved through the implementation of sustainable ecosystem approaches for the benefit of humankind (Kumar & Kanaujia, 2014). Thus, changes in the ecological character of any wetlands by human alteration basically results in the adverse change or the negative impairment in any of the functions and benefits of the wetlands as captured in the definition of change in the ecological character by University of Ghana http://ugspace.ug.edu.gh 12 Dugan & Jones (1993) which states that human-induced changes on wetlands include altered hydrological regimes; nutrient pollution, physical alteration in the form of the land use and land cover, the loss of habitat and the introduction of alien flora and fauna (Ramsar Convention Secretariat, 1996). A variety of other management efforts have been undertaken over the years by continents and countiries to counteract many of the factors leading to wetland loss. Some of the strategies adopted to ameliorate the loss of wetlands included the MedWet initiative adopted by the European Commission in the early 1990s, among governmental and non-governmental bodies to conserve the Mediterranean wetlands. This initiative was to stop and reverse the rapid degradation of all Mediterranean wetlands in their effort to conserve biodiversity sustainably in the region (Ramsar, 2016). The Glob Wetland Africa, launched by the European Space Agency and the Ramsar Secretariat was an initiative strategy to use satellite observations as an effective tool for the conservation, wise use of all wetlands, especially in Equatorial Africa (globwetland- africa.org). In Ghana, the Ghana Coastal Wetlands Management Project (CWMP) was implemented by the Wildlife Division of the Forestry Commission in 1991 to protect and manage the five designated coastal wetland sites by using the ‗wise use‘ concept to maintain the integrity of the wetlands and also enhance the benefits derived from the wetlands by local communities (Finlayson et al., 2000, Nukpezah, 2001). University of Ghana http://ugspace.ug.edu.gh 13 2.2 Wetlands in Ghana Three major types of wetlands are identified in Ghana and these are the marine/coastal wetlands, inland wetlands, and man-made wetlands (Ministry of Lands and Forestry, 1999). The marine/coastal wetlands are within the coastal zones of Ghana and are primarily associated with flood plains of estuarine and large rivers while the inland wetlands are associated with shallow freshwater bodies. Humans have created man-made wetlands for aquaculture, salt harvesting, water storage, and urban/industrial use (Ministry of Lands and Forestry, 1999, Agbemehia, 2014). Apart from the enormous benefit coastal wetlands provide in Ghana, there are major threats if not tackled, will lead to the destruction and degradation of the coastal ecosystem in Ghana. Excessive human use of the wetland, such as overfishing, excessive collection of mangroves, widespread drainage and cultivation for farmlands, heavy grazing by cattle and animals, and an unsustainable amount of salt winning are some of the primary dangers to Ghana's coastal wetlands (Ntiamoa-Baidu, 1991, Yeboah et al., 2013). Additional threats to most coastal wetlands in Ghana include the increased use of pesticides and herbicide in farming activities, the damming and creating of channels for the purpose of expanding infrastructure, and the dumping of solid and liquid waste onto wetlands (Nonterah et al., 2015). The main driver of change of these coastal wetlands in Ghana is the increase in human population encroaching coastal wetlands and through their activities like agriculture has led to modification of the land to obtain food and other essentials resources. The increase in fertilisers, organic manure from livestock and other agrochemicals substantially increase the pollution load of surface water by runoff, pollution of groundwater by leaching of excess nutrients which may have a negative effect on waterbodies and biodiversity on the wetlands (Islam & Weil, 2000; Dye, 2003; Nonterah et al., 2015). University of Ghana http://ugspace.ug.edu.gh 14 2.3 Waterbirds The Ramsar Convention defines waterbirds as species of birds that are ―ecologically dependent upon wetlands‖ (Bolduc, 2009). They are categorised as seabirds (e.g. gulls and terns), shorebirds/waders (e.g. plovers, sandpipers, stilts) and waterfowl (e.g. ducks). Waterbirds are ecologically dependent on wetlands which serve as stopover sites along their migratory flyways. They use wetland habitats for foraging, nesting, roosting, moulting and comfort activities. More than a third of all non-migratory birds live on wetlands, and at least half of all migratory birds, depend on wetlands for temporary habitat (Bradshaw et al., 2020). Waterbirds are key biodiversity groups widely used in monitoring wetlands value and status, as well as being used as bioindicators of wetland quality (Scott & Rose, 1996, Ahulu et al., 2006). Waterbirds on wetlands represent an important tool in biodiversity conservation, due to their conspicuousness, abundance, high species turnover, and sensitivity to changes and are useful in determining the quality of the wetland in which they live as their abundance on wetlands may be an indication of the abundance of preys such as fishes and macroinvertebrates on which they feed (Temple & Wiens, 1989). Waterbirds also provide many supporting and provisioning services such as the dispersal of seeds vital in agricultural and also in fisheries as indicators of rich fish stock in the sea. Although they provide all these enormous services they are mostly exploited as food in many parts of the world (Ahulu et al., 2006; Krcmar et al., 2010). University of Ghana http://ugspace.ug.edu.gh 15 2.3.1 Waterbird distribution and abundance on wetlands in Ghana Waterbird distribution may be categorised as large-scale or local as large scale patterns in waterbird distribution are mainly due to their natural occurrence on wetlands, whereas local distribution is mainly influenced by food distribution within the wetlands (Piersma et al., 1993, Knutson et al., 1999). Waterbirds may be abundant or widely distributed on wetlands if there are the presences of safe roosting sites in such ecosystems and the availability of prey items within the wetlands (van Gils et al., 2003; Blanc et al., 2006). According to Piersma & Ntiamoa-Baidu (1995) and Battley et al., (2003) waterbirds concentrate in areas with high food density. Waterbirds feed on a large variety of food ranging from macroinvertebrates (e.g. plovers), small fishes (Black-winged Stilt and Herons) to seeds and plants (herbivorous ducks). However, most individual birds choose their foraging habitats based on expected food intake rate rather than food density, though there is a strong correlation between bird distribution and food density (Piersma et al., 1993). Coastal wetlands in Ghana are key habitats for permanent and wintering Palearctic migrant waterbirds that migrate across the East Atlantic and Mediterranean flyways (Smit & Piersma, 1989). Migrant waterbirds come on the Ghanaian coast primarily in August and September, and stay until April. The peak numbers of waterbirds usually occur from September to October and another peak season in March (Ntiamoa-Baidu et al., 2014). Waterbirds are most abundant during the dry season when water levels on wetlands are generally low. The shallow water levels expose large mudflats and offer favourable conditions for foraging (Ntiamoa-Baidu et al., 2014). University of Ghana http://ugspace.ug.edu.gh 16 Waterbird population monitored on key wetland sites along the Ghana coast initiated under the SSBP-G in 1988 estimated 48 species of waterbirds during a 12-year survey period on the Muni wetland. Of the 48 species, 29 species were waders of which nine species together accounted for 94% of the total of 72,860 waders counted during the survey period (Ntiamoa- Baidu, 2000). The Sakumo II site supported about 66 waterbird species on the Ghana coast and internationally important populations of six wader species including the spotted redshank, greenshank, curlew sandpiper, little stint, black-tailed godwit (Ntiamoa-Baidu & Gordon, 1991). Gbogbo and Attuquaefio (2010) recorded a total of 198,836 individual waterbirds belonging to 59 species over two non- breeding seasons on both the protected and non- protected wetlands in the Greater Accra of Ghana. A total of 25 waterbird species, of which 11 were waders, three were terns, one gull and 10 other species belonging to 10 families totaling 20, 217 individuals were reported on the Keta Lagoon (Anyanui, Anloga, Woe, and Floodplains) and the Muni Lagoon by Lamptey & Ofori-Danson (2014). Waterbirds recorded at the Keta lagoon site accounted for 97.7% of the total count compared to 2.3% on the Muni lagoon (Lamptey & Ofori-Danson (2014). 2.4 Water quality of coastal wetlands Pollution of water bodies on coastal wetlands may originate from two main sources, point sources and diffuse sources (non-point sources) (Pierce et al., 1998). Point sources are pollutants that enter watercourses through pipes or channels whereas non-point sources come from farm runoff, construction site and other land use land cover disturbances (Pierce et al., 1998). The accumulation of contaminants from terrestrial, freshwater, and marine habitats has been discovered to be sensitive and a pollutant in most coastal wetlands (UNEP, 1995). University of Ghana http://ugspace.ug.edu.gh 17 Wetlands are known to process pollutants due to their unique properties due to the hydric nature of the soils. However, with high pollution load, the assimilative capacity of wetland gets exceeded and get polluted with nutrients, trace and heavy metals which in turn become very toxic and harmful to wetland biodiversity and to human health (UNEP, 1995). The discharge of industrial and domestic sewerage and the dumping of refuse into coastal environments increases the organic loadings of the coastal waters making the waters turbid with increase in plant growth of algal blooms which further leads to an increased levels of pH and turbidity producing toxins and odour detrimental to aquatic and human health (Wild 1995; Gopalkrusna, 2011). Studies on the hydrology of most coastal wetlands located near densely populated urban areas and industrial establishments are known to be grossly polluted (Fianko et al., 2013; Nonterah et al., 2015, Doamekpor et al., 2018). Wetlands like the Chemu lagoon in Tema, Korle and Kpeshie lagoons in Accra, Fosu lagoon in Cape Coast are all in different states of degradation due to impacts of human practices. Thus, the waters of these wetland lagoons are highly turbid and contain high levels of BOD, suspended solids as well as toxic and harmful heavy metals (Doamekpor et al., 2018). 2.4.1 Impact of water quality on waterbird distribution Poor water quality with high concentrations of pollutants endangers many aquatic species especially macroinvertebrates and waterbirds (Cao et al., 1996). Pollution through anthropogenic activities causes very low dissolved oxygen content in water while high nutrient pollution causes eutrophication and result in the decrease and functional feeding activity of biodiversity residing in a particular ecosystem like macroinvertebrates and waterbirds (Duan et al., 2011). Water depth, a key water quality parameter affects available food resources as it limits access University of Ghana http://ugspace.ug.edu.gh 18 by some waterbirds and can also influence invertebrate populations, which provide an important food source for waterfowl (Ntiamoah-Baidu et al., 1998; Baschuk et al., 2012). Salinity is a vital variable in the management of waterbird habitats. Generally, high salinity is detrimental to the distribution of waterbirds as waterbirds that drink highly saline water loose body weight due to dehydration (Hannam et al., 2003, Ma et al., 2010). High water salinity is also unbearable to fish, renders such floodplains and wetlands inhabitable by waterbirds due to their inability to find food (Lamptey et al., 2013). Heavy metals are common pollutants in aquatic environments released from anthropogenic sources which are non-biodegradable and thus accumulate in the environment over time and become toxic to organisms (Islam et al., 2015). In the aquatic environment, heavy metals are adsorbed by suspended solids and sink into bottom sediments which are ingested into the bodies of macroinvertebrates and eventually waterbirds through foraging (Ciutat et al., 2005, Ali et al., 2021). 2.5 Sediment quality of coastal wetlands Sediments provide a deeper understanding of the long-term pollution status of any coastal environment as sediments act as ready sink or reservoir of pollutants including trace and heavy metals (Onyari et al., 2003, Islam et al., 2015). Heavy metals are introduced into the bottom sediment by two means, the natural processes and human activities by means of direct discharges or dumping (Clark, 2001, Ali et al., 2021). The pollution history of any aquatic ecosystem can be studied through sediments analysis as sediments provide useful information about the water quality from past period (Oyewale & Musa, 2006). Pollution load indices have been employed by many researchers to investigate the behaviour of heavy metals in the environment (Addo et al., 2011; 2012, Rabee et al., 2011; Akoto et al., 2017). University of Ghana http://ugspace.ug.edu.gh 19 Pollution load indices are widely used methods for assessing the possibility of any negative ecological consequences of heavy metal contamination in sediments. They are environmental pollution control techniques and tools for determining the pattern of metal contamination in sediments (Abdullah et al., 2015). Pollution indices like geo-accumulation index (Igeo), enrichment factor (EF), contamination factors (CF) and pollution load index (PLI) have been used extensively to establish pollutant distribution in sediments (Samir et al., 2006; Addo et al., 2011, Bentum et al., 2011, Abdullah et al., 2015). The enrichment factor (EF) of metals is a useful indicator basically reflecting the status and degree of environmental contamination of sediments (Feng et al., 2004). The enrichment factor informs the researcher the source of the metals polluting the environment whether they are from natural processes of rocks or from anthropogenic sources while the contamination factor (CF) and pollution load indices (PLI) relates the concentration of the elements with their geochemical background reference values (Manoj & Pradhy, 2014) to find out if the site is polluted with the particular metal. The pollution load index (PLI) assesses the pollution status of any heavy metals in a particular site on a wetland (Tomlinson et al., 1980). 2.5.1 Impact of sediment quality on macroinvertebrates and waterbird distribution Direct impacts of sediment pollution on aquatic organisms especially macroinvertebrates includes being lethal as well as reduced fertility and fecundity in organisms which are polluted by sediment pollution (Ford et al., 2003, Townsend et al., 2009). Environmental stress, such as the accumulation of inorganic contaminants (Richardson et al., 2000), has a significant impact on benthic invertebrates. For example, the accumulation of heavy metals in sediments could lead to the death of benthic invertebrates (Lee et al., 2006). Metal contamination has been shown to have several consequences on benthic communities, including decreased density University of Ghana http://ugspace.ug.edu.gh 20 (Winner et al., 1980, Diggins & Stewart 1998), a drop in the number of vulnerable taxa (LaPoint et al., 1984), and changes in species distribution patterns (Clements, 1994, Clements et al., 2010). Studies in other parts of the world have shown that heavy metals can also have an influence on the general health of some waterbirds (Janssens et al., 2003; Dauwea et al., 2004). Contaminants such as cadmium, mercury, and selenium have revealed to negatively affect the condition of birds by reducing their growth or body weight (Takekawa et al., 2002). The effect of heavy metals like chromium, lead and cadmium on the embryo of the mallard bird showed that the Cr, Pb and Cd had a negative effect on the hatching and embryonic development of the bird thereby affirming that heavy metals may have an impact on the growth and nestling stage of the eggs (Bize et al., 2002). 2.6 Benthic macroinvertebrates Benthic macroinvertebrates are sedentary aquatic fauna found in the bottom soils of their habitats at least for a greater part of their life cycle (Idowu & Ugwumba 2005, Basu et al., 2018). Benthic macrofauna performs important roles in nutrient cycling and a major source of food for other aquatic waterbirds especially waders (Jana & Manna, 1995). Benthic macroinvertebrates are an essential part of the food web as they play a critical role in the natural flow of energy and nutrient as well as a link in the aquatic food chain (Gordon, 2000; Basu et al., 2018; Nuamah et al., 2018). Macroinvertebrate feed on these leaves, algae, and bacteria, which are at the lower end of the food web. In turn, macroinvertebrates also become a source of energy (food) for larger animals such as fish, which in turn also act as a source of food for birds and amphibians (Aggrey- Fynn et al., 2011). They are also used as bioindicators to assess the quality of water as they frequently respond to pollution stress in polluted ecosystems (Ikomi et al., 2005). Studies on benthic University of Ghana http://ugspace.ug.edu.gh 21 macroinvertebrates response to pollution have been carried out in a number of countries including Ghana (Thorne & Willians, 1997, Lamptey &Armah, 2008; Abdourahamene, 2010; Baa-Poku et al., 2013, Nuamah et al., 2018). Baa-Poku et al., (2013) observed that the Nima Creek was indicative of a disturbing urban creek with effluents negatively impacting macroinvertebrate assemblage. Ikomi et al., (2005) also reported pollution status on the composition, distribution, and abundance of macroinvertebrates in the upper reaches of River Ethiope, Delta State, Nigeria. 2.6.1 Macroinvertebrate abundance and its impact on waterbird distribution In many environments, benthic macroinvertebrates play a significant role in food chains (Frost et al., 2009). Multiple environmental factors, such as anthropogenically caused contaminants and changes in physicochemical and biological conditions in aquatic ecosystems, have a significant impact on their species richness and diversity (Frost et al., 2009; Rumisha et al., 2012). Sensitive macroinvertebrate species hardly survive in polluted aquatic habitats as a result of their diverse responses to disturbances, impacting waterbirds that may frequent the aquatic environment (Connell et al., 2009). Waterbirds are known to rely heavily on benthic macroinvertebrates for food (Grond et al., 2015), and the quantity of benthic macroinvertebrates available on wetlands is considered to be critical for the short- and long-term survival of shorebirds, given their high energy demands throughout migration and mating season (Zhang et al., 2016). Aquatic macroinvertebrates function as a link between producers and higher-level consumers such as waterbirds (Baldwin et al., 2018). Many factors influence macroinvertebrate distribution which directly or indirectly influences waterbirds, this include water and sediment quality, quality vegetation, and healthy wetlands (Zmudczyska-Skarbek et al., 2009). University of Ghana http://ugspace.ug.edu.gh 22 2.7 Fishery resource in coastal wetlands in Ghana Sarotherodon melanotheron is a group of tropical, hardy, fast-growing fresh cichlid which lives in fresh to brackish water environments between the depths of 0-3 metres (Hoover, 2006). Sarotherodon melanotheron is native to West Africa and acquired its name from the patches of black colour that usually occur on their neck and throat (Teugels & van den Audenaerde, 2003; Mireku et al., 2016). Studies have shown that Sarotherodon melanotheron is the most dominant and abundant species in the coastal lagoon in Ghana (Koranteng, 1995, Shenker et al., 1998, Entsua-Mensah et al., 2000, Mireku et al., 2016). Fish populations have been reported to be on the decline mainly attributed to degradation in the water quality in which they inhabit and periodic phenomena of low water inflows and floods (Ayoola & Kuton, 2009), habitat complexity as well as inputs such as agrochemicals from agricultural and urban land uses through human activities (Fausch & Bramblett, 1991). The assessment of fish especially the growth parameters and the condition factor provide a detail understanding of the fish‘s length-weight relationship (LWR) (Dulčić & Kraljević, 1996) on the wetland they inhabit. The growth parameter ―b‖ in the length-weight equation shows whether the growth of fishes is in the coastal lagoons exhibit either isometric or allometric growth. The growth parameter value is always between 2 and 4 and most often closer to 3. If the fish grows isometrically, then the growth exponent takes the value of 3. A value significantly larger or smaller than 3 indicates allometric growth, (positive allometric if b >3, negative allometric if b < 3) (Ricker, 1979, Solomon et al., 2017). On the length weight studies in previous studies, Pauly (1976) reported maximum standard length of 19 cm for tilapia collected from the Sakumo II lagoon, Ntiamoa-Baidu (1991) reported standard length ranging from 2.8 –12.1cm whilst Sawyerr et al., (2015) recorded a University of Ghana http://ugspace.ug.edu.gh 23 standard length ranging from 2.63 - 12.86 cm also in the Sakumo II lagoon. Similarly studies by Koranteng (1995) during a report prepared for the Ghana Wildlife Department recorded standard lengths ranging from 3.0-11.6cm and 2.9-10cm respectively for 200 fish samples each of Sarotherodon melanotheron collected from both the Sakumo II and Densu Delta. Dankwa et al., (2004) also reported standard lengths of tilapia ranging from 1.5–12.1cm and 3.0-10.2 cm on both the Songor and Keta lagoons respectively. For the growth parameter, Blay and Asabere Ameyaw (1993) during a study on the assessment of Sarotherodon melanotheron, in a close lagoon in Ghana found the Sarotherodon melanotheron in the Fosu lagoon to exhibit negative allometric growth (b = 2.65) for 500 fish samples. Similarly, Koranteng (1995) documented negative allometric growth patterns (b= 2.63 and b= 2.77) for the black chin tilapia in the Sakumo II and Songor lagoons respectively. The condition factor explains generally the condition of the fishes in their aquatic environment and is based on the length-weight parameters. The condition factor (CF) is an estimation of the general well-being of fishes and is based on the assumption of either the fish is being heavier at a given length or lighter at a given length. The condition factor of 1.0 or > 1 indicates good condition for fishes in their aquatic environment while condition factors < 1.0 indicate a stressful environment for fishes in their habitat (Khallaf et al., 2003; Solomon et al., 2017). Previous studies on fish condition by Mireku et al., (2016) estimated a condition factor for male Sarotherodon melanotheron between 3.95 - 4.94; while that for females ranged from 4.08 - 4.99 for a total of 457 S. melanotheron collected in the Brimsu reservoir. The high condition factor recorded indicated a good water environment for S. melanotheron. In other parts of Africa, Solomon et al., (2017) recorded very high condition factor values for fish University of Ghana http://ugspace.ug.edu.gh 24 species like the periwinkle (Tympanotonus fuscatus), in the Okrika estuary, Niger-Delta Nigeria. The high mean condition factor value of 18.9 showed that the fish species collected were in good favourable conditions although the creek received refinery effluents in large amounts from the catchment. 2.7.1 Condition of fish as an indicator of waterbird distribution Waterbirds and inland and coastal fisheries are intricately linked (Green & Elmberg 2014). Waterbird populations are dropping over the world as a result of habitat loss, disturbance, or changes in habitat quality, which are occasionally induced by fishing activities (Green & Elmberg, 2014; Bundy et al., 2017). Waterbird wintering ranges have shrunk as wetlands have shrunk, causing changes in diet and habitat use patterns in many waterbird assemblages. Aquatic communities including fish assemblage and other species act as biological indicators of water quality and serve as food for waterbirds (Davis, 1993). Fishes can be used to detect changes in the natural environment, monitor the presence of pollution in the ecosystem in which the organisms lives especially in water for the presence of contaminants (Davis, 1993). Fish abundance often significantly affects habitat use by waterbirds (Kloskowski et al., 2010; Russell et al., 2014). Aquatic environments supporting large number of fishes may be used by an assemblage of diving, piscivorous waterbirds (Paszkowski &Tonn, 2000). Fish-eating waterbirds always benefit from increases in fish populations (Lammens, 1999), whereas decrease in fish population adversely affect waterbird distribution especially for the diving piscivorous birds (Van Eerden et al., 1993) Humans have a long history of altering aquatic ecosystems through wetlands, agricultural runoff, and small to large-scale fishing activities, all of which can have an impact on habitat quality, fish quantity, and waterbird assemblage variety (Atkinson et al. 2010; Lunardi & Macedo 2013). According to several studies, waterbirds may congregate in response to a University of Ghana http://ugspace.ug.edu.gh 25 seasonal rise in fish quantity (De Nie 1995; Warke & Day 1995; Battley et al., 2003). In reaction to improved fish stocks, the population size of several species of cormorants increases dramatically (De Nie 1995; Warke & Day 1995). Fish are concentrated in narrow, shallow regions by social foraging of mixed species assemblages of herons, egrets, and long- legged shorebirds, permitting active predation (Battley et al., 2003). 2.8 Land use land cover changes (LULCC) on wetlands Land use/land cover changes on wetlands are mostly driven by anthropogenic activities or natural phenomenon which causes changes that impact human lives either positively or negatively (Loveland et al., 2003, Kamusoko & Aniya, 2007). The land cover of any wetlands encompasses the physical landscape which includes the forest, vegetative features, open water, bare lands, and the non-vegetative features while land use is the activities performed by humans on the land leading to either a change in the physical landscape (Xiangmei et al., 2016, Izakovicová et al., 2018). Land use and land cover are usually used together to avoid ambiguity (Lillesand et al., 2004). Physical changes in the land use and land cover may impact on wetlands either positively or negatively, spatially or temporally, but however, the balance is always tilted to the negative in most wetlands (Global Land Project, 2005). Human populations through agricultural activities modify land through the increase use of fertilisers, organic manure from livestock and other agrochemicals which substantially increase the pollution load of surface water by runoff and also the groundwater by leaching of excess nutrients which may have a negative effect on waterbodies and biodiversity inhabiting it (Islam & Weil, 2000). Discharging domestic, agricultural and industrial waste on the ecosystem increases both nutrients load and the toxic heavy metals which in turn seriously contaminate the waterbodies endangering flora and fauna of the ecosystem (Dye, 2003). University of Ghana http://ugspace.ug.edu.gh 26 2.8.1 Effect of LULC changes on biodiversity and waterbirds Wetland degradation has a significant impact on waterbirds, as harvesting or introducing exotic species reduces the value of the wetland, making it of little or no use to wetland- dependent waterbirds (Stewart, Jr., 2016). The presence of surface water or sediments, as well as the duration and timing of flooding, alter the value of a wetland to a given waterbird species, as a shift or possible change causes a decline in waterbird abundance (Stewart, Jr., 2016). According to Ma et al., (2010), in addition to providing food for waterbirds in the form of seeds, leaves, tubers, and rhizomes, vegetation, which is a component of wetlands, is an important habitat that influences waterbird habitat use, as the effect and importance of vegetation varies depending on the season and waterbird group. The numbers of biodiversity often drastically reduce by changes in LULC when land is transformed from primary forest to other land use forms (Oteng-Yeboah, 1994). Non-native plant, animal, and disease incursions may also be more common in areas exposed to LULC alterations, particularly in areas closer to human settlements (Ryan & Ntiamoa-Baidu, 2000). Changes in vegetation, waterbodies, terrain, and mudflats of wetlands may alter the distribution and abundance of benthic macroinvertebrates, affecting the wetland's role as a waterbird feeding ground (Pan et al., 2006) 2.9 Conceptual frame work for the study In view of the importance of coastal wetlands in Ghana to support biodiversity, a conceptual framework was designed in line with the objective of the study to understand how some of these ecosystem variables such as water and sediments, macroinvertebrates, fish, LULC changes affect the quality of the wetlands and its ability to support the abundance and distribution of waterbirds. University of Ghana http://ugspace.ug.edu.gh 27 Waterbirds are highly sensitive to environmental changes so they are considered excellent indicators of ecosystem health species and closely linked with surface water habitats (Bibby, 1999; Ogden et al., 2014). Therefore, understanding the mechanisms and ecological variables that drive waterbird distribution and abundance is important to biodiversity and ecological conservation and wetlands management (Jamoneau et al., 2018; Li et al., 2019) Figure 2.1 Conceptual framework showing linkages between ecosystem variables and waterbird abundance Legend: The framework indicates how the various ecological variables impact on the distribution and abundance of waterbirds on the wetlands selected for the study. The water quality, sediment quality, macroinvertebrate assemblage, the condition factor of fish and the land use land cover changes are expected to influence the distribution and abundance of waterbirds either directly or indirectly from the above model. Water quality Sediment Macroinvertebrate Waterbirds Land use land cover changes (LULCC) Fish University of Ghana http://ugspace.ug.edu.gh 28 The conceptual framework in Figure 2.1 shows how water quality parameters will affect benthic macroinvertebrate in the bottom sediments and how it in turns will affect the distribution and abundance of waterbirds. The framework further shows how LULC variables will be affected by water quality and its effect on waterbirds distribution, likewise, how water quality parameters will impact on the condition factor of the predominant fish in the lagoons and how they intend predict the distribution and abundance of waterbirds on the selected wetlands. This study will further show how these ecological variables fill the gap of inadequate data and research findings on how LULC variables such as vegetation cover, built-up, landmass of waterbodies, macroinvertebrate assemblage, water and sediment quality, condition and wellbeing of fish affect the abundance and distribution of waterbirds on the protected Sakumo II and most importantly the unprotected Laloi and Kpeshie wetlands in Ghana. University of Ghana http://ugspace.ug.edu.gh 29 CHAPTER THREE METHODOLOGY 3.1 STUDY AREAS The study was carried out in three coastal wetlands sites: Sakumo II, Laloi and Kpeshie lagoons within the Greater Accra Region of Ghana over twelve months from August 2017 to July 2018. The GPS coordinates of all sampling locations within the study areas have been provided in Table 3.1. The Sakumo II wetland is a designated Ramsar site while the Laloi and Kpeshie wetlands are unprotected and not designated Ramsar sites. 3.1.1 Sakumo Ramsar Site 3.1.1.1 Location The Sakumo Ramsar site is located within the Tema Municipal Assembly (TMA and comprises a coastal lagoon and floodplain. The Sakumo Ramsar site covers a total area of 13.4 km 2 (Gbogbo & Attuquayefio, 2010). The Sakumo lagoon on the wetland is permanently connected to the sea by an open sluice on the Accra-Tema Fishing Harbour road. University of Ghana http://ugspace.ug.edu.gh 30 Fig 3.1 Google Earth Map of the Sakumo Ramsar site (2018) 3.1.1.2 Population The settlements which directly impact on the wetlands are Sakumono, Tema, Lashibi, Ashaiman, and Tema Newtown and together these settlements make a total population of 483,745 of which 48.3% are male and 51.7% are female (GSS, 2014a) 3.1.1.3 Vegetation The vegetation of the Sakumo Ramsar site is typical of the vegetation in most coastal zones of Ghana (Plate 3.1). The dominant vegetation found in the freshwater marsh is the succulent forbs, Sessuvium portulacastrum. The Imperata cylindrical dominates the higher ground areas. Other important species found on the site include Paspalum vaginatum, Sporobolos virginicus, Avicennia africana (Ntiamoa-Baidu & Gordon, 1991). 3.1.1.4 Fauna The Sakumo II wetland supports large numbers of sea and seashore birds. The site serves as a habitat for some 66 waterbird species with an estimated population of 32, 500 birds (maximum count of individuals). Over 80% of the waterbird species at the Sakumo wetland are Palearctic migrants which are most abundant on the site between September and April (Ntiamoa-Baidu et al., 2001). University of Ghana http://ugspace.ug.edu.gh 31 The lagoon serves as nesting grounds for marine turtles; Olive ridley (Lepidochelys olivacea), Green turtle (Chelonia mydas) and Leatherback turtle (Dermochelys coriacea), all of which are of conservation concern (Seminoff, 2004; Abreu-Grobois & Plotkin, 2008; Tiwari et al., 2013). Fish species observed in the lagoon include the black-chin tilapia (Sarotherodon melanotheron) (most abundant), Bonga shad (Ethmalosa fimbriata), mullets Mugil spp. (uncommon), snappers (Lutjanus spp.), Senegalese ladyfish (Elops senegalensis) and Caranx spp. (Ntiamoa-Baidu & Gordon, 1991; Asmah et al., 2008), Alestes baremoze, Heterobranchus bidorsalis and Oreochromis niloticus (Sawyerr et al., 2015). Invertebrates recorded on the site include polychaetes, mollusc, crustaceans (Acartia spp), Cladocera (water flea), guineashrimp, southern pink shrimp and other insects (Gordon, 1995). 3.1.1.5 Land Use The major land use within the Sakumo II Ramsar site includes arable agriculture, animal grazing, fishing, fuelwood gathering, housing, and industrial development. The wetland is primarily used for agriculture cultivation as rice, cassava, and many other vegetable farming activities are undertaken mostly on the northern parts of the wetland and also along the banks of the rivers within the wetlands (Nonterah et al., 2015). University of Ghana http://ugspace.ug.edu.gh 32 3.1.2 Laloi coastal wetlands 3.1.2.1 Location The Laloi lagoon and its catchment falls is located at Prampram and enters the sea at Kpone which lies in the Tema Export Processing Zone (Gordon et al., 1998). The lagoon is located behind the El Din Salt Mills Company Ltd at Prampram which has been operational for the past 40 years on the wetland. Fig 3.2 Google earth map of the Laloi coastal wetland (2018) 3.1.2.2 Population The settlement which directly impacts on the Laloi coastal lagoon includes Prampram Township, Vakpor, Kpoi-Ete, and Dawhenya. Together, these settlements make up about 22,562 of the population of the district (GSS, 2014b) University of Ghana http://ugspace.ug.edu.gh 33 3.1.2.3 Vegetation The vegetation within the lagoon and its catchment are made up of mangroves and rushes community which includesAvicennia spp, Paspalum vaginatum, Imperata cylindrical and Sesuvium portulacastrums .The edges of the lagoon water are dominated by Typha domingensis, a salt resistant aquatic plants (Attuquayefio & Gbogbo, 2001) 3.1.2.4 Fauna The Laloi lagoon and its catchment support about 48 species of waterbirds of international importance (Gbogbo & Attuquayefio, 2010). The site supports an international population of waders such as the Bar-tailed godwit, Little Stint, Black-tailed godwit, Common Redshank, Black-winged stilt, Sanderlings and terns such as the royal tern, roseate tern and common tern (Gbogbo & Attuquayefio, 2010). The site also supports important fish species like the black-chin tilapia Sarotherodon melanotheron (most abundant), Bonga shad Ethmalosa fimbriata, mullets Mugil spp. (uncommon), snappers (Lutjanus spp) (Koranteng, 1995). University of Ghana http://ugspace.ug.edu.gh 34 Plate 3.1 Fish species caught from the Laloi lagoon during the study by a fisher 3.1.2.5 Land Use The major land use within the catchment includes farming, animal rearing, fishing, fuelwood gathering, salt mining, housing, and industrial development. There are few vegetable farms located upland from the lagoon which has a tendency of nutrient leaching into the lagoon when it rains (Badu Bortey, 2012). 3.1.3 Kpeshie Coastal Wetland 3.1.3.1 Location The Kpeshie lagoon and its catchment is located between the Teshie Military Barracks and the Trade Fair site. The Kpeshie lagoon is an open lagoon to the sea with only one broad opening under a constructed bridge (Addo et al., 2011). University of Ghana http://ugspace.ug.edu.gh 35 Fig 3.3 Google Earth Map of Kpeshie wetland (2018) 3.1.3.2 Population The Kpeshie catchment includes the La Township, Burma camp, Labone, Cantoment and Airport. Together the catchment has a population of 183,528 with females constituting 52.7% while the males constitute 47.3% of the entire population. The Kpeshie wetland and its catchment is entirely urban (GSS, 2014c). 3.1.3.3 Vegetation The vegetation of the Kpeshie lagoon and its catchment consists of dense clusters of small trees, shrubs, and grasses, which grow to an average height of about six metres (GSS, 2014c). The Kpeshie catchment has a good cover of mangrove vegetation as shown in Plate 3.4 consisting mainly of white mangrove Avicennia germinans with bottom mangrove Conocarpus erectus as a minor component which serves as a nursery ground for fishes and other marine life Typha spp., Cyperus articulants, Panicum maximum, Paspalum spp., Sporobolus spp. make up the grassland in and around the wetland (Ansah et al., 2011). University of Ghana http://ugspace.ug.edu.gh 36 Plate 3.2 Relatively dense vegetative cover around the Kpeshie lagoon 3.1.3.4 Fauna The wetland and its catchment support important waterfowl species. The site supports waterbird species such as the African Jacanna, Senegal Thick-knee, Whimbrel, Senegal Wattled plover, etc. (Koney, 2010). The sand dunes on the beach of the site are used as roosting sites for marine turtles. Fish species in the lagoon on the wetland include the Sarotherodon melanotheron, Bonga shad (Ethmolsa fimbriata), grey mullets (Mugil and Liza spp.,) and mudskipper (Periophthalmus papilio). Shellfishes found in the lagoon include the blue legged swimming crab (Callinectes ammicola), and the fiddler crab (Uca tangerii) (Ansah et al., 2011). 3.1.3.5 Land use The soils within the catchment are mostly used to grow vegetables and fruits for both domestic and commercial purposes (Ansah et al., 2011). Most of the land and the lagoon sites are being used for the construction of houses, roads, estates, recreational facilities like football fields and other developmental projects as shown in Plate 3.3. University of Ghana http://ugspace.ug.edu.gh 37 A. Road constructed over the Kpeshie lagoon B. Reclaiming of land for residential purposes at Kpeshie C. Construction of buildings along the Kpeshie lagoon catchment D. Land cleared for football AstroTurf at Kpeshie wetland Plate 3.3 Land use within the Kpeshie lagoon and its catchment University of Ghana http://ugspace.ug.edu.gh 38 3.2 Study design and data collection The study was carried out from August, 2017 to July, 2018. The study used both quantitative and qualitative data. The methods used during the study included direct field observations and laboratory analysis of samples collected. 3.2.1 Sampling Points 3.2.1.1 Description of sampling points The locations of the sampling points were determined using a handheld GPS device (Garmin GPSmap 62). The sampling points are indicated in Table 3.1. All sampling sites were selected based on accessibility and the anthropogenic activities around the location using a map of the study area as shown in Figure 3.4.  SS (Sakumo South)-is the southern part of the lagoon and connects the lagoon to the sea via two culverts.  SM (Sakumo Middle) - is the middle portion of the lagoon where fishing activities concentrated around this part of the lagoon.  SN (Sakumo North) - is the northern part of the lagoon closer to the industries and settlements. University of Ghana http://ugspace.ug.edu.gh 39 Fig 3.4 Map of Sakumo coastal wetland showing sampling points For the Laloi coastal wetland, sampling was done on locations as shown in Figure 3.5.  LN (Laloi North) – this is the northern part of the lagoon which has other streams flowing into the wetland.  LM (Laloi Middle) – this is the middle portion of the lagoon which has most fishing activities and closer to the saltpans  LS (Laloi South) – this is the southern part of the lagoon where lagoon water enters the sea  LA (Laloi Salt Pans) – this is the area where salt mining is being undertaken by El- Din Salt Mills Ltd. University of Ghana http://ugspace.ug.edu.gh 40 Fig 3.5 Map of the Laloi coastal wetland showing all the sampling points The sampling sites at the Kpeshie coastal wetland from where samples were collected are indicated in Figure 3.6.  KB (Kpeshie Bridge) – samples were collected under the bridge on the Kpeshie lagoon  KT (Kpeshie-Teshie Road) - Samples were collected along the road heading towards Teshie township.  KS (Kpeshie-Sea end) - Samples were collected from the area connecting to the sea adjacent La Palm Royal Beach Hotel.  KA (Kpeshie Africa Lake) – Samples were collected from the African Lake area which is connected to the Kpeshie lagoon by culverts. University of Ghana http://ugspace.ug.edu.gh 41 Fig 3.6 Map of Kpeshie coastal wetland showing sampling point University of Ghana http://ugspace.ug.edu.gh 42 3.2.1.2 Sampling site and sampling locations Table 3.1 below shows the sites and location water, sediment, macroinvertebrate samples were collected during the study period. Table 3.1: GPS points of sampling sites Site Name Latitude Longitude Sakumo South (SS) N 50 36' 53.61'' W 00 1' 58.12'' Sakumo Middle (SM) N5 0 37' 13.76'' W 00 2' 8.28'' Sakumo North (SN) N 50 37' 31.20'' W 00 2' 21.34'' Laloi North (LN) N 50 42' 58.49'' W 00 4' 25.83'' Laloi Middle (LM) N 50 42' 24.8'' W 00 4' 29.48'' Laloi South (LS) N 50 41' 58.49'' W 00 4' 22.2'' Laloi Salt Pans (LA) N 50 42' 30.52'' W 00 4' 37.5'' Kpeshie Bridge (KB) N 50 33' 56.38'' W 00 8' 8.34'' KpeshieTeshie Road (KT) N 50 33' 59.41'' W 00 8' 0.16'' Kpeshie Sea end (KS) N 50 33' 52.02'' W 00 8' 7.56'' Kpeshie African Lake (KA) N 50 33' 56.04'' W 00 8'29.34'' University of Ghana http://ugspace.ug.edu.gh 43 3.2.2 Land use land cover data acquisition and image preprocessing Landsat Thematic Mapper satellite images for 1986, 2002 and 2017 were freely downloaded from the United States Geological Survey website (https://ear th