Wild pollinator communities of commercial almond plantations and native woodland in a semi-arid ...

238 Pages·2014·2.42 MB·English

by  Manu E Saunders

Wild pollinator communities of native woodlands and commercial
almond plantations in a semi-arid Australian landscape:
Implications for conservation of insects and ecosystem services
Manu E Saunders
B Arts; B Env Sc (Ecology) Hons, University of Queensland
July 2014
This thesis is submitted in fulfilment of the degree of Doctor of Philosophy
Charles Sturt University
Faculty of Science
School of Environmental Sciences
Supervisors: Professor Gary W Luck
Professor Geoff M Gurr
Dr Margaret M Mayfield (UQ)
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Table of Contents Page
Preface viii
Acknowledgements ix
Abstract xi
List of Figures xiii
List of Tables xiv
PART I: GENERAL BACKGROUND 1
Chapter 1: Introduction and Scope 3
1.1 Agroecosystem function 3
1.2 Insects as purveyors of ecosystem functions 4
1.3 Aims and Scope 6
1.4 Justification of terms used in this work 8
Chapter 2: Study system and sampling protocol 11
2.1 Study area 11
2.2 Mallee woodlands and shrublands 12
2.3 Almond cultivation in the Mallee 15
2.4 Sampling protocol 16
PART II: ANALYSIS 19
Chapter 3: Almond orchards with living ground cover host more wild 23
pollinators
3.1 Introduction 24
3.2 Methods 27
3.3 Results 37
3.4 Discussion 44
Chapter 4: Wild pollinators in flowering almond orchards and 49
proximity to unmanaged vegetation
4.1 Introduction 50
4.2 Methods 52
4.3 Results 59
4.4 Discussion 65
Chapter 5: The influence of a semi-arid woodland—almond 71
plantation edge on wild pollinator communities
5.1 Introduction 72
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5.2 Methods 75
5.3 Results 81
5.4 Discussion 88
Chapter 6: Food and habitat resources available to wild pollinators in 95
a late winter flowering crop
6.1 Introduction 96
6.2 Methods 99
6.3 Results 104
6.4 Discussion 114
PART III: SYNTHESIS 121
Chapter 7: Synthesis and Conclusions 123
7.1 Synthesis and general discussion 123
7.2 Conclusions 126
PART IV: REFERENCE MATERIAL 129
Literature Cited 130
Appendix 1: Pan trap catches of pollinator insects vary with habitat 163
(published manuscript)
Appendix 2: Taxonomic lists of flower visitor observations and trap 183
samples
Appendix 3: Full set of models for analyses of ground cover vegetation— 197
pollinator relationships (Chapter 3)
Appendix 4: Location attributes and pollinator occurrence along ecotone 202
gradients (Chapter 5)
Appendix 5: Physical attributes and full candidate sets of models for 211
analysis of habitat structure relationships (Chapter 6)
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Certificate of Authorship
I hereby declare that this submission is my own work and to the best of my
knowledge and belief, understand that it contains no material previously published
or written by another person, nor material which to a substantial extent has been
accepted for the award of any other degree or diploma at Charles Sturt University
or any other educational institution, except where due acknowledgement is made
in the thesis. Any contribution made to the research by colleagues with whom I
have worked at Charles Sturt University or elsewhere during my candidature is
fully acknowledged. I agree that this thesis be accessible for the purpose of study
and research in accordance with normal conditions established by the Executive
Director, Library Services, Charles Sturt University or nominee, for the care, loan
and reproduction of thesis, subject to confidentiality provisions as approved by the
University.
Name:
Signature:
Date:
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Preface
This thesis includes five individual manuscripts that have been published in
academic journals. Consequently, there will be some repetition across chapters,
especially within discussions of background material and methodological details.
Chapter 2 provides a brief summary of the study area and an overview of the
general sampling approach but specific methodological and analytical procedures
for each individual study are detailed in each chapter. A single reference list is
provided at the end of the thesis to avoid unnecessary duplication. I am personally
responsible for conceptualising the project, all data collection and analysis, and
the majority of written text. Gary Luck, Margie Mayfield and Geoff Gurr
contributed to the planning and sampling design stages and to the papers they
have co-authored with me.
Peer-reviewed publications from this work:
 Chapter 3: Almond orchards with living ground cover host more wild
insect pollinators. (Saunders ME, Luck GW, Mayfield MM (2013) Journal
of Insect Conservation 17:1011-1025).
 Chapter 5: Spatial and temporal variation in pollinator community
structure relative to a woodland—almond plantation boundary. (Saunders
ME, Luck GW (2014) Agricultural and Forest Entomology,
doi:10.1111/afe.12067).
 Chapter 6: Keystone resources available to wild pollinators in a winter-
flowering tree crop plantation. (Saunders ME, Luck GW, Gurr GG (in
press) Agricultural and Forest Entomology).
 Appendix 1: Pan trap catches of pollinator insects vary with habitat.
(Saunders ME, Luck GW (2013) Australian Journal of Entomology
52:106-113).
Conference presentations from this work:
 Saunders ME, Luck GW, Mayfield MM (2012) Living ground cover
influences native pollinator abundance in commercial almond orchards. 1st
Apimondia ApiEcoFlora Symposium, San Marino, Republic of San
Marino, 4-6 October 2012, poster presentation. (Chapter 3)
 Saunders ME, Luck GW (2013) Pan trap catches of pollinator insects vary
with habitat context. VII Southern Connection Congress, Dunedin, New
Zealand, 21-25 January 2013, poster presentation. (Appendix 1)
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Acknowledgements
Submission of this thesis is a beginning for me, not an end. I am especially
grateful to my principal supervisor, Gary Luck, who provided the precise relative
proportions of humour, guidance, encouragement and patience that I needed. He
gave me freedom to learn to be the ecologist I am, and direction when tangents
knocked at my door. I could not have asked for a better supervisor. My co-
supervisor, Margie Mayfield, has been an equally inspirational force, before I
even knew I was going to undertake a PhD. I cannot thank her enough for giving
me the opportunity as an undergraduate student to develop my interest in
pollination ecology and for being part of this project. I also sincerely thank Geoff
Gurr, for project advice and intellectual contributions; the Institute for Land Water
and Society and the School of Environmental Sciences, for financial,
administrative and logistic support; Simon McDonald, Deanna Duffy and Gail
Fuller, for technical support, patience with all my ignorant questions about GIS
and GPS and swiftness in delivering top-quality conference posters; the
indispensable lab staff, particularly Lauren Sheather, who helped with equipment,
field work preparation, and assistance during the long days I spent staring down a
microscope; Ken Walker for voluntary identification of my (very poorly-
mounted) native bee specimens; Select Harvests and Manna Farms, for kindly
providing access to their almond trees; and the Department of Sustainability and
Environment, Victoria, for research access to mallee national parks. Many other
people have contributed, either directly or indirectly, to me reaching this point (in
no particular order): Alison Matthews, Lisa Smallbone, Paul Humphries, Nicole
McCasker, Ian Lunt, Gill Earl, Janet Cohn, Katrina Lumb, Tobias Smith, Peter
Spooner, Wayne Robinson, Antonio Castro, Simon Watson, Saul Cunningham,
Alan Yen, Michael Batley, Peter Lillywhite, Gimme Walter and Barbara
Gemmill-Herren. James, you and Sarge have kept me afloat over the last 3.5
years, and there would have been more tears than smiles without you and the
music. Most importantly, I thank my mother for teaching me to believe in what
truly matters.
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