Co-introduction of metazoan parasites with an invasive host, Micropterus salmoides (Lacépède, 1802) in non-native regions in South Africa M Truter orcid.org/0000-0002-0091-1598 Dissertation submitted in fulfilment of the requirements for the Masters degree in Environmental Science at the North-West University Supervisor: Prof NJ Smit Co-supervisor: Prof OLF Weyl Assistant Supervisor: Dr I Přikrylová Graduation May 2018 23378123 Table of Contents ________________________________________________________________________________________________________________________________________________ Table of Contents List of Figures ................................................................................................................... iv List of Tables ..................................................................................................................... vi Acknowledgements ........................................................................................................ viii Abstract .............................................................................................................................. x Keywords ......................................................................................................................... xiii Study Outputs ................................................................................................................. xiv Chapter 1: General Introduction 1.1. Largemouth bass: a global invader ......................................................................... 5 1.2. Associated parasites: native and non-native range ................................................ 6 1.3. Hypotheses ............................................................................................................. 8 1.4. Aims and Objectives ............................................................................................... 8 Chapter 2: Materials and Methods 2.1. Selection of localities ............................................................................................ 10 2.1.1. North West (NW) ............................................................................................ 10 2.1.2. KwaZulu-Natal (KZN) ..................................................................................... 14 2.1.3. Eastern Cape (EC) ......................................................................................... 14 2.1.4. Western Cape (WC) ....................................................................................... 14 2.2. Sampling of host species ...................................................................................... 17 2.2.1. Micropterus salmoides ................................................................................... 17 2.2.2. Other fish species .......................................................................................... 17 2.3. Necropsy, blood parameters, biometric indices and parasite screening ............... 19 Chapter 3: Parasite communities of South African Largemouth bass Micropterus salmoides (Lacépède, 1802) populations: support for enemy release 3.1. Introduction ........................................................................................................... 21 3.2. Materials and Methods ......................................................................................... 22 3.2.1. General .......................................................................................................... 22 Page i | 116 Table of Contents ________________________________________________________________________________________________________________________________________________ 3.2.2. Parasite fixation, morphology and identification ............................................. 22 3.2.3. Statistical analysis .......................................................................................... 23 3.3. Results .................................................................................................................. 23 3.3.1. General parasitological data ........................................................................... 23 3.3.2. Parasite community: composition, diversity and richness .............................. 25 3.3.3. Morphological characterisation ....................................................................... 27 3.4. Discussion ............................................................................................................ 36 Chapter 4: Molecular characterisation of ancyrocephalid monogeneans parasitising Micropterus salmoides in South Africa 4.1. Introduction ........................................................................................................... 42 4.2. Materials and Methods ......................................................................................... 43 4.2.1. DNA extraction and Polymerase Chain Reaction ........................................... 43 4.2.2. Sequence alignment and phylogenetic analysis ............................................. 44 4.3. Results .................................................................................................................. 47 4.4. Discussion ............................................................................................................. 54 Chapter 5: Host health and parasitic infection 5.1. Introduction ........................................................................................................... 56 5.2. Materials and Methods ......................................................................................... 58 5.2.1. General .......................................................................................................... 58 5.2.2. Statistical analysis .......................................................................................... 60 5.3. Results .................................................................................................................. 60 5.3.1. Fish health and organosomatic indices .......................................................... 60 5.3.2. Blood parameters ........................................................................................... 63 5.4. Discussion ............................................................................................................ 65 Chapter 6: Parasite spill-over from Largemouth bass (Micropterus salmoides) to native freshwater fish species: a biological invasion case study 6.1. Introduction ........................................................................................................... 68 6.2. Materials and Methods ......................................................................................... 69 6.2.1. General .......................................................................................................... 69 6.3. Results .................................................................................................................. 70 6.3.1. General and parasitic infection ....................................................................... 70 6.4. Discussion ............................................................................................................ 75 Page ii | 116 Table of Contents ________________________________________________________________________________________________________________________________________________ Chapter 7: Concluding remarks and recommendations for future studies 7.1. Introduction ........................................................................................................... 79 7.2. Concluding remarks .............................................................................................. 79 7.3. Future studies ....................................................................................................... 80 References ....................................................................................................................... 82 Page iii | 116 List of Figures ________________________________________________________________________________________________________________________________________________ List of Figures Chapter 1 Figure 1. 1. Categorisation scheme for the invasion process with introduced species into a novel environment (adapted from Richardson et al., 2000, Colautti and MacIsaac, 2004; Blackburn et al., 2011). ........................................................................................................ 2 Figure 1. 2. Schematic representation of co-introduced and co-invasive parasites. Alien host has a parasite that follows process of introduction, establishment and spread with original host. Parasite switches to native host (blue) to become a co-invader (adapted from Lymbery et al., 2014). .......................................................................................................... 7 Chapter 2 Figure 2. 1. Map of the localities throughout South Africa where the field sampling for the present study was carried out. ........................................................................................... 11 Figure 2. 2. Specific sites where host specimens were collected. A – C: Mooi River, Potchefstroom Dam and Boskop Dam (North West); D – Friedrichkrön Dam (KwaZulu- Natal); E – F: Howison’s Poort Dam and Settlers Dam (Eastern Cape); G – H: Groenvlei Lake and Vergenoegd Farm Dam (Western Cape). .......................................................... 16 Figure 2. 3. Methods used to collect host specimens; A – rod and reel; B – fyke nets; C – gill nets;