Amy Deacon Phd Thesis

THE BEHAVIOURAL ECOLOGY OF THE TRINIDADIAN GUPPY, POECILIA RETICULATA, AS AN INVASIVE SPECIES Amy E. Deacon A Thesis Submitted for the Degree of PhD at the University of St. Andrews 2010 Full metadata for this item is available in Research@StAndrews:FullText at: https://research-repository.st-andrews.ac.uk/ Please use this identifier to cite or link to this item: http://hdl.handle.net/10023/1689 This item is protected by original copyright This item is licensed under a Creative Commons License The behavioural ecology of the Trinidadian guppy, Poecilia reticulata, as an invasive species A thesis submitted for the degree of Ph.D. at the University of St Andrews Amy E. Deacon September 2010 Abstract This thesis focuses on the guppy, Poecilia reticulata, as an invasive species. Its non- native distribution, the biology behind its success and the reasons for its introduction are examined. A worldwide email survey revealed that the guppy is established in at least 73 countries outside of its native range and that mosquito control schemes and the release of unwanted aquarium fish are the two primary routes of introduction. Knowledge gaps were identified; primarily the scarcity of scientific evidence for negative impacts of guppy introductions and similarly for mosquito control efficacy. Replicated mesocosm experiments demonstrated that female guppies are capable of routinely establishing populations, and that these retain behavioural viability over several generations. The first mesocosm study suggested that founders with very different evolutionary histories were equally good at establishing populations. The second mesocosm study suggested that monandrous females were extremely successful at establishing behaviourally viable populations, with no decline in behavioural variation. Two related foraging experiments attempted to examine the effectiveness of guppies as mosquito control agents. The first study found little evidence for the presence of ‘prey switching’ in guppies, questioning the validity of previous work advocating their introduction to stabilise prey populations. The second study revealed a preference for non-vector mosquito larvae in a two-prey system. However, both mosquito species were consumed equally readily when habitat complexity increased. The presence of conspecifics affected female foraging behaviour. The presence of males reduced the strength of prey preference in the first study, and an interaction between social and habitat factors affected prey preference in the second. Both demonstrate that multi-prey systems have important implications for the efficacy of poeciliids in biological control. Despite severe demographic bottlenecks, their adaptability and ability to rapidly increase in numbers enable guppies to establish and persist when introduced. Such bottlenecks are typical of introduction scenarios, warning that particular caution should be exerted when introducing this species, or other live-bearing fish, to natural water bodies. Acknowledgements Firstly, I would like to thank Professor Anne Magurran for her excellent supervision throughout my studentship; providing structure and ideas whilst also allowing me the freedom to explore my own. I always leave Anne’s office full of confidence and renewed enthusiasm. I am especially grateful for the travel and outreach opportunities she has encouraged and facilitated alongside my Ph.D. My studentship was funded by NERC. My work in Trinidad would not have been possible without Professor Indar Ramnarine, who welcomed me on each of my trips as well as providing laboratory space, equipment and field assistants. He also allowed guppies to colonise the roof of the Life Sciences Department. Kharran Deonarinesingh and Raj Mahabir provided invaluable help catching wild fish and monitoring the mesocosms. I thank Dr Darren Croft, Dr Safi Darden and Dr Katherine Jones for useful discussions in the early stages of the behavioural experiments while in Trinidad. I am also grateful to Caya Sievers for her company and assistance. The work in India was in collaboration with Dr S. K. Ghosh and Dr S. N. Tiwari, who made our stay in Bangalore a very enjoyable experience. I would also like to thank Mahesh Jaiswal and numerous other staff at the NIMR. Dr Anuradha Bhat’s enthusiastic help was invaluable to this work, not least in bridging communication barriers! I am indebted to Dr Sophie Smout, Dr Will Cresswell and Dr Monique McKenzie for statistical advice. Thanks are due to Cormac Booth, Clint Blight and René Swift for helping me get to grips with GIS and Manifold, and to Jimmy Murdoch for feeding the guppies. Anne Magurran, Alex Sansom, Anuradha Bhat and Sophie Smout also read chapter drafts, for which I am extremely grateful. I also thank my examiners, Will Cresswell and Tino Macías Garcia, for insightful comments and a productive viva. I feel very lucky to have shared this journey with Tess, Alex, Valentina and Emma, without whom the experience wouldn’t have been anywhere near as fun. I am also grateful to many other colleagues and friends in St Andrews, in particular: Alice; Amir; Anu; Caya; Claire; Cormac; Des; Felicity; Iain; Jane; Jeff; Katie; Maria; Marion; Mark; Miguel; Mike; Pam; Peter; René; Sol; Stephanie; Tanya; Thomas; attendees of the Behavioural Discussion Group, Bionetwork and Fish Lunch; Luke, Claudia, Dylan & Nico; Clint, Irv and everyone from Unihoc; DABS and the Music Quiz team. Finally, I thank my family and oldest friends for their unconditional support, and for always being just a phone call away. Declaration I, Amy Deacon, hereby certify that this thesis, which is approximately 38,000 words in length, has been written by me, that it is the record of work carried out by me and that it has not been submitted in any previous application for a higher degree. I was admitted as a research student in September 2006 and as a candidate for the degree of Ph.D. in September 2006; the higher study for which this is a record was carried out in the University of St Andrews between 2006 and 2010. Date Signature of candidate I hereby certify that the candidate has fulfilled the conditions of the Resolution and Regulations appropriate for the degree of Ph.D. in the University of St Andrews and that the candidate is qualified to submit this thesis in application for that degree. Date Signature of supervisor In submitting this thesis to the University of St Andrews we understand that we are giving permission for it to be made available for use in accordance with the regulations of the University Library for the time being in force, subject to any copyright vested in the work not being affected thereby. We also understand that the title and the abstract will be published, and that a copy of the work may be made and supplied to any bona fide library or research worker, that my thesis will be electronically accessible for personal or research use unless exempt by award of an embargo as requested below, and that the library has the right to migrate my thesis into new electronic forms as required to ensure continued access to the thesis. We have obtained any third-party copyright permissions that may be required in order to allow such access and migration, or have requested the appropriate embargo below. The following is an agreed request by candidate and supervisor regarding the electronic publication of this thesis: Access to Printed copy and electronic publication of thesis through the University of St Andrews. Date Signature of candidate Signature of supervisor Contents 1. General introduction 1 1.1 Invasive species 1.2 Predicting invaders 1.3 The guppy as an ideal study species 1.4 The guppy as an invasive species 1.5 What makes the guppy a successful invasive species? 1.6 Foraging behaviour of introduced guppies 1.7 Aims 2. Worldwide survey of invasive guppies: distribution, origins 24 and impacts Abstract 2.1 Introduction 2.2 Methods 2.3 Results 2.3.1 – Distribution 2.3.2 – Origins 2.3.3 – Continent-by-continent summary 2.3.4 - Impacts 2.4 Discussion 3. Colonisation success in an invasive species: single female 50 guppies routinely establish viable populations Abstract 3.1 Introduction 3.2 Methods 3.2.1 – Mesocosm set-up 3.2.2 – Population assessment 3.2.3 - Newborn performance 3.2.4 - Courtship vigour 3.2.5 – Statistical analysis 3.3 Results 3.3.1 – Establishment success 3.3.2 – Life history and population structure 3.3.3 – Newborn performance 3.3.4 – Courtship vigour 3.3.5 – Results summary 3.4 Discussion 3.4.1 – Establishment success 3.4.2 – Life history and population structure 3.4.3 – Newborn performance 3.4.4 – Courtship vigour 3.4.5 – General discussion in the context of introduced species 4. Polyandry and colonisation success in the guppy 82 Abstract 4.1 Introduction 4.2 Methods 4.2.1 – Mesocosm set up 4.2.2 – Population size and structure 4.2.3 – Male colouration 4.2.4 – Newborn performance 4.2.5 – Courtship behaviour 4.2.6 – Statistical methods 4.3 Results 4.3.1 – Establishment success 4.3.2 – Life history and population structure 4.3.3 – Male colouration diversity 4.3.4 – Newborn performance 4.3.5 – Courtship vigour 4.3.6 – Behavioural variation 4.3.7 – Results summary 4.4 Discussion 5. The effect of conspecifics on foraging behaviour in the 108 guppy: prey switching? Abstract 5.1 Introduction 5.2 Methods 5.2.1 – Experimental methods 5.2.2 – Statistical methods 5.3 Results 5.4 Discussion 6. The foraging behaviour of the guppy in relation to its use in 131 the biological control of mosquito larvae Abstract 6.1 Introduction 6.2 Methods 6.2.1 – Experimental methods 6.2.2 – Statistical methods 6.3 Results 6.3.1 – Prey consumption: social experiment 6.3.2 – Prey consumption: habitat complexity experiment 6.3.2 – Prey preference 6.3.3 – Results summary 6.4 Discussion 7.

Load more