1 THE UNIVERSITY OF HULL Breeding Ecology, Migration and Population Genetics of Lesser Crested Terns Thalasseus bengalensis emigrata being a Thesis submitted for the Degree of Doctor in Philosophy in the University of Hull by Abdulmula Abdulmagid Hamza B.Sc., M.Sc.Zoology, M.Res.(Biodiversity and Conservation) February 2014 i Table of Contents Table of Contents ............................................................................................................ i List of Figures ................................................................................................................v List of Tables ............................................................................................................... viii List of abbreviations used in this thesis ........................................................................ xi Acknowledgements ...................................................................................................... xii Abstract ....................................................................................................................... xiii Chapter 1. Introduction .............................................................................................. 2 1.1 Introduction ............................................................................................................. 2 1.2 Ornithological literature review ................................................................................ 4 1.2.1 Breeding seabirds of Libya .................................................................................. 5 1.2.2 Non-breeding (wintering) Seabirds of Libya ........................................................ 6 1.2.3 Lesser Crested Terns in Libya ............................................................................. 6 1.2.4 Lesser Crested Terns in North and West Africa ................................................ 10 1.2.5 Conservation status ........................................................................................... 11 1.2.6 The Mediterranean Seabirds Action Plan .......................................................... 13 1.3 Aims, objectives, hypotheses and structure of the Thesis .................................... 17 1.3.1 Aims and objectives ........................................................................................... 17 1.3.2 Structure of the Thesis ....................................................................................... 17 Chapter 2. The breeding biology of Lesser Crested Tern Thalasseus bengalensis in Libya ...................................................................................................................... 19 2.1 Introduction ........................................................................................................... 20 2.2 Aims, Objectives and hypothesis .......................................................................... 22 2.3 Description of study areas and methods .............................................................. 22 2.4 Breeding Ecology parameters .............................................................................. 30 2.4.1 Breeding dates ................................................................................................... 30 2.4.2 Colony formation and breeding population size ................................................ 31 2.4.3 Breeding synchrony ........................................................................................... 32 2.4.4 Egg volume, nesting density and inter-nest distances ...................................... 32 2.4.5 The incubation period ........................................................................................ 33 2.4.6 Reproductive success ........................................................................................ 34 ii 2.4.7 Hatching and breeding productivity ................................................................... 34 2.4.8 Nest failures ....................................................................................................... 34 2.4.9 Statistical analyses ............................................................................................. 35 2.5 Results .................................................................................................................. 35 2.5.1 Breeding dates ................................................................................................... 35 2.5.2 Colony formation and breeding population size ................................................ 36 2.5.3 Breeding synchrony ........................................................................................... 41 2.5.4 Egg volume, nesting density and inter-nest distance ........................................ 42 2.5.5 Effect of colony size on mean egg laying initiation date .................................... 47 2.5.6 The incubation period ........................................................................................ 47 2.5.7 Hatching, fledging success and breeding productivity ....................................... 48 2.5.8 Nest failures ....................................................................................................... 49 2.6 Discussion ............................................................................................................. 50 Chapter 3. Feeding Ecology of Lesser Crested Tern nestlings ........................... 68 3.1 Introduction ........................................................................................................... 68 3.1.1 Feeding in Lesser Crested Terns ...................................................................... 70 3.1.2 Hypotheses ........................................................................................................ 71 3.1.3 Objectives and research questions .................................................................... 72 3.2 Methods ................................................................................................................ 72 3.2.1 Introduction ........................................................................................................ 72 3.2.2 Identification of food items ................................................................................. 73 3.2.3 Data analysis ...................................................................................................... 74 3.3 Results .................................................................................................................. 76 3.3.1 Nestlings diet structure in terms of frequency and mass ................................... 76 3.3.2 Dissimilarity ratios in diet structure of Lesser Crested Tern young ................... 84 3.3.3 Temporal distribution of reconstituted mass in the young’s diet at Elba colony 91 3.3.4 Temporal distribution of reconstituted mass in the young’s diet at Gara colony 94 3.3.5 Temporal distribution of reconstituted mass in the young’s diet at Jeliana colony ..................................................................................................................................... 97 3.3.6 Distribution of prey total length (TL) at the three breeding sites ...................... 100 3.6.7 Prey mass distribution at the three breeding sites ........................................... 102 iii 3.3.8 Temporal distribution of prey mass at the three colonies ................................ 103 3.3.9 Prey sizes during the later provisioning period ................................................ 104 3.3.10 Species richness at each sampling site (Rarefaction method): .................... 106 3.3.11 Breeding productivity and diet species diversity ............................................ 107 3.4 Discussion ........................................................................................................... 108 Chapter 4. Ringing and migration of Mediterranean breeding Lesser Crested Terns Thalasseus bengalensis emigrata ............................................................. 123 4.1 Introduction ......................................................................................................... 123 4.1.1 Aims and Objectives ........................................................................................ 124 4.1.2 Hypotheses ...................................................................................................... 124 4.2 Materials and Methods ........................................................................................ 125 4.3 Results ................................................................................................................ 129 4.3.1 Ringing operations ........................................................................................... 129 4.3.2 Post-natal movements (staging and wintering areas) ..................................... 130 4.3.3 Post-natal movements (wintering range) ......................................................... 132 4.3.4 Mortality at wintering range .............................................................................. 133 4.3.5 Site fidelity and recruitment .............................................................................. 136 4.4 Discussion ........................................................................................................... 139 Chapter 5. Population Genetics of the Lesser Crested Terns Thalasseus bengalensis ......................................................................................... 145 5.1 Species