Aggression and competition in two boreal animals. By Jennifer E. Van Eindhoven A thesis submitted in conformity with the requirements for the degree of Master of Science. Ecology and Evolutionary Biology University of Toronto © Copyright by Jennifer Elizabeth Van Eindhoven 2012 Aggression and competition in two boreal animals. Jennifer E. Van Eindhoven Master of Science Ecology and Evolutionary Biology University of Toronto 2012 Abstract: This thesis will focus on the use of agonistic behaviour in both direct and indirect competition in two arboreal species: the eastern chipmunk (Tamias striatus) and Cyphoderris monstrosa, a primitive orthopteran insect. Chipmunks are an example of indirect competitors as they are competing for finite resources for dealing with abiotic stresses to ensure their survival. Chapter 2 of this project investigates the behavioural time budget for above ground activity at a time of critical importance for overwinter survival. The chipmunks in this study displayed a focus of their time budget on eating and collecting food in preparation of winter survival while they were above ground. Chapter 3 of this research project studies the physiological differences between males of Cyphoderris monstrosa which engage in aggressive territorial contests. The data suggest that metabolic scope is correlated with RHP. Males’ ability to mobilize energy reserves may be an important factor in contest outcomes. ii Acknowledgements I would like to start off by thanking my parents John Van Eindhoven and Debbie Spencer (married to my stepdad Dick) for always opening their warm homes and hearts whenever I need them. Whether its phone calls, dinners, emails, texts, baked goods, time spent away from technology, walks with the dogs you always know what I need to put everything into perspective. I love you so much and I am very grateful that I was able to go through this with you behind me 110% and being my biggest supporters. A big thank you goes to Brendan Delehanty and Lanna Desantis for the technical assistance, guidance, general acceptance into the lab and for teaching me how to trap small mammals. Importantly, I would like to extend a thank you to my close friend and field assistant Bryan Taylor. Bryan, thank you for all of your hard work in the field and for the personal support when things became difficult both professionally and personally for me. I truly do value all of the work you did with me and how great of a friend you are. I would also like to thank the members of the Mason Lab: Dean Koucoulas, Norman Lee, Paul DeLuca and Sen Sivalinghem for welcoming me into their lab. You all have been the source of thoughtful discussions and personal support. Maria Modanu you have been more than patient and kind when teaching me how to use the respirometry equipment which is a large part of the Cyphoderris project. My committee members (Ken Welch, Maydianne Andrade and Andrew Mason) have all been a wealth of information and understanding. Ken you have been beyond helpful when trying to get through the respirometry data. You have also given rise to thought provoking discussions and challenging questions that keep me on top of things when preparing for meetings. Maydianne thank you so much; you were my saving grace when it came to dealing with a difficult situation, without your guidance and support I truly feel that the personal outcome of this degree would be drastically different. I honestly can’t express the gratitude that I feel. I need to say thank you to you, Andrew and the powers that be for providing me with an alternative when I didn’t know that there was one. In turn, Andrew, thank you for accepting me into your lab. I honestly felt that I would end up somewhere that was suitable to obtain my degree and just bare down and get through it, however what I found was a lab full of people that mean a great deal to me, research that I find interesting and exciting and a supervisor that I am honoured to have. You’re guidance in the past year personally and professionally has meant a great deal to me and I am beyond thankful for that. iii Table of Contents Acknowledgements ........................................................................................................................ iii Table of Contents ........................................................................................................................... iv List of Tables ................................................................................................................................. vi List of Figures ............................................................................................................................... vii Chapter 1: General Introduction ......................................................................................................1 Chapter 2: Indirect competition 1 Chapter 3: Direct competition 3 Chapter 2: The Behavioural Time Budget of the Eastern Chipmunk (Tamias striatus) While Preparing for the Induction of Winter Sleep………………………………………………………8 Introduction 8 Methods 12 Animals 12 Radio Telemetry 13 Behavioural Observations 13 Statistical Analysis 14 Results 15 Early October Behavioural Analysis 15 Late October Behavioural Analysis 16 Alteration in Behaviour over Time 16 Discussion 17 Chapter 3: Competitive signalling during aggressive encounters in the primitive acoustic insect Cyphoderris monstrosa (Orthoptera: Haglidae). ............................................................26 Introduction 26 Animal Contests: evolution 26 Animal Contests: energetics 27 Study Species 27 Methods 32 Animals 32 Fight Tournament 33 Energetic Rate Measurements 34 Song and Physical Characteristics 35 Statistical Analysis 37 Results 38 Tournament Results 38 Morphology Comparisons 38 iv Metabolic Measurements 39 Discussion 39 Behavioural Patterns 39 Morphometrics 40 Metabolism 41 Chapter 4: General Conclusion ......................................................................................................51 Literature Cited ..............................................................................................................................53 v List of Tables Table 1: Categories of chipmunk behaviour and descriptions 21 Table 2: Principal components analysis of male C. monstrosa morphology measurements 44 Table 3: Male C. monstrosa tactics on the outcome of staged territorial contests 45 Table 4: Male C. monstrosa status (winner/loser) with PCA of morphological measurements 46 vi List of Figures Figure 1: Number of observations of chipmunks for each week of study 22 Figure 2: The daily time budget in Early October (Oct 5-8, 2011) 23 Figure 3: The daily time budget in Late October (Oct 18-21, 2011) 24 Figure 4: The change in displayed behaviour from Early to Late October 25 Figure 5: Distribution of Cyphoderris in North America 47 Figure 6: Relationship of duty cycle and weight 48 Figure 7: Carbon dioxide production of singing males and their duty cycles 49 Figure 8: Metabolic scope of Winners and Losers in relation to their duty cycles 50 vii Chapter 1 General Introduction Competition is any interaction between individuals or species, sharing limited resources, that is mutually detrimental to both participants. Individuals competing for the same resources or objects with one another where physical interference occurs is direct competition, competition for resources without direct contact between individuals or the resource itself is indirect competition (Eccard et al, 2011; English-Loeb et al., 1993). Competition for resources between different species (interspecific competition) can occur for the use of an area or access to food sources and it can present within a species (intraspecific) for mate selection and gathering of specific food items. Thus the type of competition an individual faces in securing sought after resources is related to various conditions and pressures. This research paper will focus on agonistic behaviour in both direct and indirect competition in two arboreal species. Chapter 2: Indirect competition-a behavioural ecology approach Canada’s landscape is in a continuous state of transformation by the change of seasons throughout the year. One of the most extreme seasons is winter because of very cold temperatures and snow coverage. Animals deal with this in three very distinct ways. The first option is avoidance; some species (like many bird species) choose to migrate to southern areas and remove themselves from the extreme weather. This involves a great deal of stress as the animals have to travel great distances to reach subtropical to tropical regions (Speakman and Rowland, 1999). Geese species around the world travel approximately 3000 ground kilometers south every fall (Pennycuick et.al. 2011) and caribou move hundreds of miles from their winter ranges in the taiga and their summer ranges on the tundra (Frame et al., 2008). The other radical option is to remain in the area and enter hibernation. Through reducing energy requirements and 1 experiencing a severe drop in body temperature, these individuals are able to cope with the lack of available resources needed to sustain their normal daily energy requirements. Hibernators, for example insectorivous bats (Speakman and Rowland, 1999) and the North American woodchuck (Marmota monax) (Peppas et al., 2009), usually prepare for this by storing high levels of fat, which is used as the energy source for their survival, before entering their shelter for the entire winter. Lastly, there are species that are neither able to