PHILOPATRY AND THE SPATIAL STRUCTURING OF KIN IN THE RED-BREASTED MERGANSER (MERGUS SERRATOR) David J. Fishman Department of Natural Resource Sciences McGill University, Montreal September 2010 A thesis submitted to McGill University in partial fulfilment of the requirements of the degree of Masters of Science (M.Sc.) © David Fishman 2010 DEDICATION To my mother and father who have taught, and continue to teach me about what it is to be a good human being. ii ABSTRACT The detection of genetic-spatial structures has been facilitated by the advancement and increased accessibilities of molecular technologies. Using an empirical genetics approach, we explore aspects of the ecology of red-breasted mergansers (Mergus serrator) nesting on barrier islands off the coast of New Brunswick, Canada. Objectives were three-fold: first, to compare two sources of genetic material, i.e. blood and contour feathers, on the basis of quantity and quality of the nuclear DNA yielded; second, to screen several heterologous microsatellite primers in the M. serrator genome in order to find polymorphic loci which could subsequently be implicated in ecological analyses; third, to characterize spatial patterns of relatedness across this colony. DNA was successfully obtained from both blood and feather samples; that originating from blood was obtained at a much higher yield (µg) while the feather-derived DNA was more pure. Altogether 12 microsatellite primers successfully amplified products from the M. serrator genome. Of these, four were genotyped across 46 genetic samples and moderate levels of allelic variability were observed. Significant deviations from Hardy-Weinberg equilibrium were apparent at two loci. Finally, genetic-spatial structuring was observed within the colony over both broad and fine-scales. KEYWORDS: waterfowl, philopatry, kin associations, microsatellites, nesting synchrony, cooperative nesting, Mergus serrator iii RÉSUMÉ La détection des structures génétiques spatiales a été facilitée par l'avancement et accessibilités accrue des technologies moléculaires. En utilisant une approche empirique génétique, nous explorons les aspects de l'écologie de harles huppés (Mergus serrator) nichant sur les îles de la barrière au large des côtes du Nouveau-Brunswick, Canada. Les objectifs étaient de trois ordres: d'abord, de comparer les deux sources de matériel génétique, le sang et les plumes de contour, sur la base de la quantité et la qualité de l'ADN nucléaire, en deuxième lieu, à l'écran plusieurs amorces hétérologues microsatellites dans le génome M. serrator des loci polymorphes qui pourrait ensuite être impliqués dans les analyses écologiques, en troisième lieu, pour caractériser les patrons spatiaux de parenté dans cette colonie. L'ADN a été obtenu avec succès des deux échantillons de sang et de plumes; celle qui provient du sang a été obtenu avec un rendement beaucoup plus élevé (µg) tandis que l'ADN provenant de plumes était plus pur. Au total, 12 marqueurs microsatellites amplifiés avec succès des produits à partir du génome M. serrator. Parmi eux, quatre ont été génotypés dans 46 échantillons génétiques et des niveaux modérés de la variabilité allélique ont été observés. Des écarts significatifs de l'équilibre de Hardy-Weinberg sont apparents sur deux loci. Enfin, la structuration spatiale génétique a été observée dans la colonie plus large et fine-échelles. MOTS-CLÉS: sauvagine, philopatrie, les associations proches, microsatellites, la synchronie de nidification, coopérative de nidification, Mergus serrator iv TABLE OF CONTENTS Page No. DEDICATION.................................................................................... ii ABSTRACT........................................................................................ iii RÉSUMÉ............................................................................................. iv TABLE OF CONTENTS................................................................... v LIST OF FIGURES............................................................................ vii LIST OF TABLES.............................................................................. ix ACKNOWLEDGMENTS.................................................................. xi PREFACE........................................................................................... xii CHAPTER 1: INTRODUCTION 1.1) Literature Review.................................................................... 1 1.1.1) Decisions of movement............................................... 1 1.1.2) Philopatry and dispersal............................................ 3 Ultimate factors............................................. 4 Inbreeding avoidance................................... 6 Sex-biased patterns....................................... 9 1.1.3) Kin associations.......................................................... 12 Cooperative breeding.................................... 13 Reduced aggression...................................... 14 Defense.......................................................... 15 Pre-hatch brood amalgamation................... 16 Post-hatch brood amalgamation.................. 18 1.1.4) Kin recognition........................................................... 19 1.1.5) Microsatellites and the detection of spatial Structuring of kin...………………………………… 22 v 1.2) Research Objectives................................................................. 23 1.2.1) Study system............................................................... 23 1.2.2) Objectives.................................................................... 24 1.3) Literature Cited....................................................................... 25 CONNECTING STATEMENT (1)................................................... 38 CHAPTER 2: EVALUATION OF GENETIC MATERIALS 2.1) Abstract..................................................................................... 39 2.2) Introduction.............................................................................. 40 2.3) Methods..................................................................................... 41 2.4) Results....................................................................................... 45 2.5) Discussion................................................................................. 47 2.6) Literature Cited....................................................................... 49 CONNECTING STATEMENT (2)................................................... 57 CHAPTER 3: SCREENING FOR HETEROLOGOUS MICROSATELLITE PRIMERS 3.1) Abstract..................................................................................... 58 3.2) Introduction.............................................................................. 59 3.3) Methods..................................................................................... 60 3.4) Results....................................................................................... 63 3.5) Discussion................................................................................. 64 3.6) Literature Cited....................................................................... 68 CONNECTING STATEMENT (3)................................................... 76 vi CHAPTER 4: SPATIAL-GENETIC STRUCTURING IN A RED- BREASTED MERGANSER (MERGUS SERRATOR) COLONY IN KOUCHIBOUGUAC NATIONAL PARK 4.1) Abstract..................................................................................... 77 4.2) Introduction.............................................................................. 78 4.3) Methods..................................................................................... 80 4.4) Results....................................................................................... 86 4.5) Discussion................................................................................. 90 4.6) Literature Cited....................................................................... 98 CONCLUDING STATEMENTS...................................................... 113 LIST OF FIGURES CHAPTER 2: EVALUATION OF GENETIC MATERIALS Figure 2.1 - Total amount of DNA (µg) obtained from blood and feather samples, respectively. On average, blood samples produced nearly 20X as much DNA as feather samples.…………………….....................................52 Figure 2.2 – The comparison of DNA quality expressed as the 260:280 ratio. The dashed line represents the ratio expected for pure DNA. While both were within the acceptable range of absorbance at the 260:280 ratio, there were usually higher levels of contamination found in DNA extracted from blood.......……………………………………………………………..…….53 Figure 2.3 – Two-dimensional PCoA ordination diagram. The proportion of variance explained by the first two principal coordinate axes was 0.414 and 0.225, respectfully. In this figure, the positions of the objects (i.e. nesting vii females) in relation to one another are approximations of their genetic distances. The PCoA was used in conjunction with Queller & Goodnight’s (1989) coefficient of relatedness………………………………….……...…54 Figure 2.4 – (a) Curve representing the positive-linear relationship between number of feathers used and total yield of DNA (ug). (b) The Q-Q normal plot of the model which indicates there were no major deviations from normality detected in the residuals…………………………………………55 Figure 2.5 – As a result of the second round of purification, significant changes were observed in both (a) DNA purity (t= -2.410, p-value= 0.030) as measured by the 260:280 ratio (b) total yield