Conservation of Freshwater Fishes in Saudi Arabia
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Conservation of freshwater fishes in Saudi Arabia being a thesis submitted in fulfilment of the requirements for the degree of Doctor of Philosophy in the University of Hull by IBRAHIM GABEL Z ALHARTHI October 2019 Dedication Nothing in the whole world can describe the love in mother & father hearts. I dedicate this work to my mother; I ask my God to have mercy on her. She died nine years ago and my heart shattered since then. I cannot forget all moments with her. She dreamed of seeing me reaching this stage and I am hoping to be. I am here because of you, this is for your sacrifice and for all that you have been given to me and to my siblings. I also dedicate this work to my dear father. He did a lot, cares a lot, and he still doing no matter how old he becomes, his heart is the biggest I know. I dedicate this work to my two uncles and my aunt who died during my time in the United Kingdom, and I did not know about them until after the funeral. My family were hiding their death for fear that my study would be affected by this. What an attitude made me lose the ability of speak. To my brothers and my sisters, they are best close friends. To my relatives, they always keep me in their prayers and surrounding me with positivity. Last for the special in my life, to my soulmate, she is my remedies, she is my companion in this life, she is the only one who was so jealous in a good way from the fish when I spent some time working on them, to my beloved wife, Mastourah. To my three children (Abrar, Mayar and Omar), my happiness and always they make me happy. i Acknowledgements I would like to express my sincere gratitude to my advisors Prof. Ian Cowx and Dr. Jonathan Harvey for the continuous support of my Ph.D study and related research. They are a wonderful example of great scientists that a young man like me wishes to become like them. I would also like to thank examiners Prof. Chris Goldspink and Dr. Andy Nunn for their valuable comments and suggestions. I would like also to thank all of my friends at Hull International Fisheries Institute (HIFI) for their sophisticated communication despite I am a bit shy, being kind and friendly during my research work, they made me feel I am home and inspired me with their hard working. I would like as well to thank Saudi wildlife Authority for their full support and for facilitate data collections trips, especially: Prince Bandar bin Mohammed Al Saud, former president. Vice President, Dr. Hany Tatwany . Fawaz Baroudi, Muawiyah Al-Ghamdi, Bandar Al-Faleh. I would also like to thank everyone who helped me to collect fish samples and participated in the long and arduous journeys. ii Abstract This study aims to gain fundamental knowledge to underpin the formulation of practical solutions to ensure the protection and conservation of Saudi Arabian fishes threatened by anthropogenic activities, whilst taking into account all users and stakeholders. Multivariate analysis, based on species presence/absence data in different water bodies in different regions collected from the literature and this study, was used to determine the biogeographical distribution of fish species in Saudi Arabia. Freshwater fish are mainly located within drainages in the south-west of the Kingdom, both in lowlands (western drainage systems) and highlands (eastern drainage systems) of the Sarawat Mountain Range. Importantly, this study recorded the presence of non-native fish species in the dams located in Al Baha Region, Abha and Rabigh, which means both western and eastern drainage systems are being invaded by non-native species such as Oreochromis spp. and Carassius spp. The ecology of three native (Carasobarbus apoensis, Cyprinion mhalensis, Garra buettikeri) and four non-native (Oreochromis niloticus, Poecilia latipinna, Carassius carassius and Gambusia affinis) species were studied in eight water bodies (five dams, two wadis and one lake) considered representative of the habitats occupied by freshwater fish in Saudi Arabia. Fish were caught by a variety of sampling methods (gill nets, traps and angling) in three seasons (spring [post floods], summer [extreme temperatures and drought conditions] and winter) and examined for age and growth, feeding ecology and reproductive characteristics. The growth of each species was found to vary between sites and was related mostly to habitat type and the quality of the environment. The dietary studies provided valuable information about the feeding habits of native and non-native fish species in Saudi Arabia and the how foods consumed varied between species, habitat types, size/age of fish species and with season. All species were found to be omnivorous, with varying degrees of specialism towards planktivorous, herbivorous or detritivorous diets, with the exception of Garra buettikeri, which is a planktivorous/benthivorous species. Differences in diets were found between locations and seasons for the three native species, and these were concluded to be related to variability in environmental conditions and approximation to the preferred habitat type of the species. Ontogenetic shifts in diet were found among the three native species examined, but the small individual sizes of two of the non-native species, Poecilia latipinna and Gambusia affinis, and small sample sizes of other non-natives precluded such an analysis. Little overlap was found between the food items consumed by native and non-native species, and where it was observed it was largely food items in abundant supply, such as detritus and benthic algae. Carasobarbus apoensis and Cyprinion mahalensis spawned exclusively in spring during the rainy seasons. Garra buettikeri is as batch spawner, and was reproductively active throughout the year. Oreochromis niloticus is reproductively throughout the year, and Poecilia latipinna and Gambusia affinis are viviparous species with two main periods of spawning in spring and autumn. Spawning appears to be driven by rainfall and increased productivity associated with high water events. The findings of this study were used to formulate a Saudi freshwater fish management plan targeting mainly conservation issues. The plan provides an overview of the status of the fisheries, threats, exploitation pressures and governance structures. Options for management of the fisheries are provided and the integration of freshwater fisheries in water resource management plans is stressed as an affirmative action. iii Contents Dedication ................................................................................................................................... i Acknowledgements .................................................................................................................... ii Abstract ..................................................................................................................................... iii Contents .................................................................................................................................... iv List of Figures .......................................................................................................................... viii List of Tables ............................................................................................................................ xv Chapter 1 General Introduction ................................................................................................. 1 1.1 Arabian freshwater fishes ............................................................................................. 1 1.2 Research gaps ............................................................................................................... 2 1.3 Research objectives ...................................................................................................... 3 1.4 Research contribution ................................................................................................... 3 1.5 Thesis chapters ............................................................................................................. 3 Chapter 2 Introduction to Saudi Arabian Freshwater Fishes ..................................................... 6 2.1 Paleogeography ............................................................................................................ 6 2.2 Saudi wetlands (natural and man-made) ...................................................................... 7 2.3 Problems and threats related to Saudi freshwater fishes .......................................... 10 2.3.1 Recreational and subsistence fishing .................................................................. 11 2.3.2 Non-native fish species introductions ................................................................ 13 2.3.3 Damming ............................................................................................................. 15 2.3.4 Lack of rain and prolonged droughts .................................................................. 18 2.3.5 Water quality ...................................................................................................... 18 2.3.6 Urbanization and rural areas development ........................................................ 20 2.3.7 Pastoralists and Hikers ........................................................................................ 21 2.3.8 Tropical diseases vector control (pesticides) ...................................................... 21 2.3.9 Extensive pumping of water for domestic supply and agriculture ..................... 22 2.3.10