Assessing the conservation status of the Sinai Baton Blue butterfly (Pseudophilotes sinaicus) Katy Thompson, BSc. (Hons) Thesis submitted to the University of Nottingham for the degree of Doctor of Philosophy July 2013 Abstract Arid environments are resource-limited, with scarcity of water the key limiting factor for plants and their associated fauna. Consequentially bottom-up forces often control food webs, influencing the whole system through high levels of competition. The Sinai Baton Blue butterfly, Pseudophilotes sinaicus, is Critically Endangered, with a tiny endemic distribution in the St Katherine Protectorate, South Sinai, an arid environment. Its range is restricted to that of its sole host plant, the near- endemic endangered Sinai Thyme, Thymus decussatus, leaving the butterfly in a highly fragmented distribution. This study looks into the spatio-temporal variations in quality and abundance of the host plant and its implications for the Sinai Baton Blue. Over the past decade the butterfly has exhibited severe population cycles, with the causes still unclear; it could be due to the fluctuating resource levels with large temporal variation in the quality of thyme and density of inflorescences. The number of flowers significantly influences the larval distribution, indicating that resources play a key role in offspring survivorship. Population viability analysis has also highlighted the importance of management techniques aimed at increasing the butterfly's survivorship. The butterfly population sizes are positively correlated with the total resource area and the number of host plants but not the distance between habitat patches. Population viability analysis also suggests that habitat area is more influential than connectivity in this system driving current dynamics. Overall this project has highlighted the urgent need for conservation focused on improving plant quality within patches in order to save this fragile species. i Acknowledgments There are so many people to thank for all their help and support throughout this project. Firstly and foremost I would like to thank my supervisor, Dr Francis Gilbert for his constant enthusiasm and support during this project. I am indebted to Amy Shepherd, Oliver Masters and Haithem Zalat for their help in the field collecting data along with my other colleagues from the University of Nottingham who were also working in Sinai. In particular I want to thank Olivia Norfolk and Stine Simensen; we all went majnoona together, João Pedro Pio for his never-ending antics and also Andrew Power and Lisa Gecchele for the hafla baflas. I also want to thank everyone in the B135 for moral support when time seemed to move either too slow or far too fast. I thank the Egyptian Environmental Affairs Agency and Mr Mohamed Qotb, manager of the St Katherine Protectorate, for permission to do the research; and Mr Mohamed Qotb and the staff of the St Katherine Protectorate for their help and advice during this work. Whilst working in St Katherine I was privileged to meet so many incredible Bedouin who welcomed me into their lives with such generosity and kindness. I thank my guides in the field, particularly Nasr Mansour for his insight and incredible knowledge of the area and for being the best of the best; Farag Fox, who was essential in the practicalities behind my field work; and also my Fox Camp family, especially Hamdi Mubarak, for the endless evenings drinking shai and playing the tabla. Dr Brian Taylor has been invaluable in the identification of the ant species in Sinai and Dr Luigi Sannino for his help in the identification of Heliothis peltigera. I would like to also thank Mike James for his advice and his love for the area whilst Professor Samy Zalat is responsible for setting up the research logistics behind the field work. I could not have completed this work without the financial assistance from the Carr Scholarship and also the Mohamed bin Zayed species conservation fund - thank you very much. Finally and most crucially I am forever grateful to my family for their enduring patience and support. ii Contents Chapter 1. General introduction; a brief overview of the Sinai Baton Blue 1 References 10 Chapter 2. The response of the endangered Thymus decussatus to eight years of low rainfall in an already arid environment 13 Abstract 14 Introduction 14 Materials & Methods 17 The study system 17 Mapping of Farsh Shoeib 18 Analysis of data 19 Results 20 Discussion 22 References 32 Chapter 3. Synchronous shifts in the flowering of Thymus decussatus and the flight period of the associated Sinai Baton Blue butterfly, Pseudophilotes sinaicus 36 Abstract 37 Introduction 37 Materials & Methods 40 The study system 40 Monitoring phenological timings in Farsh Shoeib 42 Monitoring the status of the Sinai Baton Blue 42 Analysis of data 43 Results 43 Discussion 44 References 53 Chapter 4. Spatio-temporal variation in a perennial herbaceous shrub, Thymus decussatus, and the associated butterfly populations of Pseudophilotes sinaicus 58 Abstract 59 Introduction 59 iii Materials & Methods 61 The study system 61 Evaluating the quality of thyme amongst patches 62 Monitoring phenology 63 Mapping of patches upon the Mt. Sinai massif 63 Monitoring the status of the Sinai Baton Blue 64 Ant sampling 64 Analysis of data 64 Results 66 Plants 66 Butterflies 67 Ants 69 Discussion 69 Spatio-temporal variation 69 Ant community composition 72 Sinai Baton Blue distribution across the Mt. Sinai massif 73 References 85 Chapter 5. Plant quality governs the larval distribution of the Critically Endangered Sinai Baton Blue butterfly (Pseudophilotes sinaicus) 90 Abstract 91 Introduction 91 Materials & Methods 92 The study system 92 Fieldwork 94 Analysis of data 95 Results 95 Discussion 97 References 105 Chapter 6. The effects of grazing on the endangered Thymus decussatus in a hyper-arid environment 109 Abstract 110 Introduction 110 Materials & Methods 113 The study system 113 Experimental manipulations 116 iv 117 Analysis of data 119 Results 119 Experimental treatments 120 Discussion 129 References Chapter 7. Predicting the future of the World’s Smallest 136 butterfly, Pseudophilotes sinaicus 137 Abstract 137 Introduction 139 Materials & Methods 143 Results 145 Discussion 156 References 160 Chapter 8. Future directions; passing on the Baton 171 References v Chapter 1. General introduction; a brief overview of the Sinai Baton Blue 1 Chapter 1. General introduction General introduction; a brief overview of the Sinai Baton Blue The Sinai Baton Blue (Pseudophilotes sinaicus Nakumara, 1975: Lycaenidae) is the World’s smallest butterfly; the smallest recorded wingspan is 6.25 mm and the average is just 9.5 mm (James, 2006b). The butterfly is Critically Endangered, with an Extent of Occurrence less than 7 km2 and an estimated total population below 3000 in 2001 (Thompson & Gilbert, 2012). Its narrowly endemic distribution is localised to the St Katherine Protectorate, South Sinai, Egypt and it is one of two endemic butterfly species to the area, the other being the Sinai Hairstreak (Satyrium jebelia: Lycaenidae). The larvae feed exclusively upon the host plant, Sinai Thyme (Thymus decussatus Bentham, 1834: Lamiaceae), restricting the distribution to a patchy formation on mountaintops at altitudes above 1800 m (James, 2006a). The population can crash dramatically between years with a crash in 2003 reducing the peak butterfly population in one patch (Farsh Shoeib) to 12% of its size in 2002 (James, 2006c). Consequentially it is considered a top conservation priority for the local Protectorate and a flagship species for the area (Hoyle & James, 2005). Figure 1.1 is a timeline demonstrating the significant events over the past decade for the Sinai Baton Blue. The adult is univoltine with the main flight period starting at the beginning of May and finishing mid-June (James et al., 2003). Adults live for 3-6 days and females mate almost immediately, with 47% mating before their first flight (James, 2006f). Females lay approximately 26 eggs, distributed singly on inflorescences across multiple thyme plants, possibly as a bet- hedging strategy to spread the risk (Bergstrom et al., 2006, James, 2006f). Larvae hatch approximately four days after oviposition and are immobile, remaining on the inflorescences on which the eggs were laid. Little is known about the larval development, but it is presumed to take approximately 21 days with four or five instars; the first two instars feed exclusively on the buds of the Sinai Thyme, whilst later instars can also feed upon the flowers (James, 2006d,f). The larvae are myrmecophilous with facultative associations with Lepisiota obtusa and Lepisiota hirsuta ants (Shepherd, 2010); the larvae were tended 71% of the time by Lepisiota species (James 2006f) with lesser associations with Monomorium niloticum ants. The larvae produce volatile secretions to attract and alert attendant ants; in return for protection, the larvae secrete simple sugars 2 Chapter 1. General introduction and amino acids from their dorsal nectary organs (James, 2006f). Crematogaster antaris ants prey upon the larvae, reflected by the fact that no adult butterflies emerged within the foraging range of C. antaris (James, 2006f). The foraging ranges of C. antaris and Lepisiota spp. are mutually exclusive, and the distributions of the two species do not overlap (Shepherd, 2010). The larvae pupate in the soil below the plant where they remain over winter, eclosing the following year. It is unknown whether the pupae can delay emergence for multiple years if conditions are sub-optimal, a tactic known in other desert Lycaenidae (Larsen, 1990). If this occurs then it might explain the low number of adults seen during the 2003 drought, otherwise attributed to mortality (James, 2006c,f). The tactic is used by Pseudalmenus chlorinda (Lycaenidae), which can remain in its pupal state for an additional year, whilst Cupha prosopa (Nymphalidae) can delay emergence for seven months. The extension of the pupal diapause in C. prosopa has been associated with unsuitable conditions, such as low rainfall (Sands & New, 2008).