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Université Du Québec À Rimouski UNIVERSITÉ DU QUÉBEC À RIMOUSKI INTRODUCTION DE DINOFLAGELLÉS NON INDIGÈNES DANS LES ÉCOSYSTÈMES AQUATIQUES CANADIENS VIA LES RÉSERVOIRS DE BALLAST DES NA VIRES Thèse présentée dans le cadre du programme de doctorat en Océanographie en vue de l'obtention du grade de philosophiœ doctor, océanographie PAR © OSCAR GABRIEL CASAS MONROY AVRIL 2012 UNIVERSITÉ DU QUÉBEC À RIMOUSKI Service de la bibliothèque Avertissement La diffusion de ce mémoire ou de cette thèse se fait dans le respect des droits de son auteur, qui a signé le formulaire « Autorisation de reproduire et de diffuser un rapport, un mémoire ou une thèse ». En signant ce formulaire, l’auteur concède à l’Université du Québec à Rimouski une licence non exclusive d’utilisation et de publication de la totalité ou d’une partie importante de son travail de recherche pour des fins pédagogiques et non commerciales. Plus précisément, l’auteur autorise l’Université du Québec à Rimouski à reproduire, diffuser, prêter, distribuer ou vendre des copies de son travail de recherche à des fins non commerciales sur quelque support que ce soit, y compris l’Internet. Cette licence et cette autorisation n’entraînent pas une renonciation de la part de l’auteur à ses droits moraux ni à ses droits de propriété intellectuelle. Sauf entente contraire, l’auteur conserve la liberté de diffuser et de commercialiser ou non ce travail dont il possède un exemplaire. 11 III Composition du jury: Philippe Archambault, président du jury, Université du Québec à Rimouski Suzanne Roy, directeur de recherche, Université du Québec à Rimouski André Rochon, codirecteur de recherche, Université du Québec à Rimouski Lucie Maranda, examinateur externe, University of Rhode Island USA. Dépôt initial le 17 Avril 2012 Dépôt final le 28 aout 2012 A mis padres y hermana por motivarme a superar mis Ifmites. A mi familia: Paola, mi principal motor, Avril mi solecito que ha sabido quebrar la soledad, Mathias mi angel en la infinidad, ... y a mis dos futuras razones de seguir siendo (Isaac y Sofia). In questions of sciences the authority of a thousands is not worth the humble reasoning of a single individual: Galileo Galilei. Always listen to those that say th ey are searching for truth, never those that say they have found it: A lbert Einstein . We are ail atheists about most of the gods that societies have ever believed in. Sorne of us just go one god further: Richard Dawkins. Vlll REMERCIEMENTS Je voudrais remercier les membres du jury de Thèse et mon comité, Dr. Philippe Archambault (président ISMER-UQAR), Dr. Lucie Maranda (examinatrice externe, URI), Dr. C.W. McKindsey (membre du comité de thèse) et mes directeurs, Dr. Suzanne Roy (directrice ISMER-UQAR) et Dr. André Rochon (codirecteur, ISMER-UQAR). Leurs commentaires et précisions constructifs apportés sur les questions examinées ont contribué grandement aux avancées de cette thèse. Plus particulièrement, je voudrais remercier mes directeurs de recherche, Suzanne Roy et André Rochon qui m'ont fait confiance en m'acceptant comme étudiant à ce projet. Merci beaucoup pour votre support tout le long de cette recherche. Je suis très reconnaissant pour votre disponibilité, pour répondre à mes questions ou pour corriger mes écrits. Merci pour cette formation dans les sciences de la mer, mais surtout pour me transmettre votre passion pour le phytoplancton, pour les dinoflagellés et leurs kystes. Merci de toute votre patience!! Merci aux chercheurs partenaires de l'Institut Maurice Lamontagne à Pêches Océans Canada, Nathalie Simard, Andrea Weise et Chris W McKindsey pour vos commentaires et votre appui scientifique dans les différents volets de cette recherche. Merci aux biologistes François Roy et Jean Yves Couture pour les heures dans les réservoirs des bateaux, où chaque gramme de sédiment ou chaque millilitre d'eau faisait la différence. Merci aux différentes équipes d'échantillonnages à Vancouver, dans les Grands Lacs, ainsi que dans l'est du pays, notamment Sarah Bailey, Elizabeta Briski, Francis Chai, Jean-Yves Couture, Rémis Daigle, Donald Humphrey, Matthieu Huot, Olivia Lacasse, Gavin Leung, Petra Logic, Colin van Overdijk et Beth Piercey. Je voudrais remercier vivement la précieuse collaboration de Marie Parenteau. Au début avec les échantillons vivants et les cultures des dinoflagellés; ensuite avec son expertise dans l'identification des cellules végétatives. Merci à Sylvie Lessard de m'avoir ouvert les portes du laboratoire de taxonomie de x phytoplancton à l'Institut Maurice Lamontagne et d'avoir partagé les références bibliographiques avec moi, quels beaux cadeaux! Merci à DomDom et Thomas, avec qui j'ai appris sur les kystes. Merci à tous les employés de l'ISMER qui m'ont aidé à résoudre les différents problèmes, que ce soit au plan administratif: Sylvie, Brigitte, Nycole, Martine, Marielle ou au niveau technique: Dominique, Mélanie, Pascal, Gilles, Sylvain et Bruno. Je remercie aussi les étudiants de mon bureau, quelle belle diversité culturelle: Sahar, Chian, Waibba, Nico, Heicke, Sarah, Eva, Jessi, Philippe. Merci d'avoir supporté ces longues journées d'obscurité, en m'épargnant de travailier sous ia iumière flegmatique des néons. Merci Nico de résoudre n'importe quel problème technique et de partager ton savoir et ta passion pour la el. Merci aux étudiants hors bureau (présents et déjà partis) et hors campus, qui m'ont aidé, qui m'ont soutenu, ou qui ont su me changer les idées pendant les moments difficiles: Aurore, Magdalena, Andréane, Amandine, Erwann, André-Anne, Max, Rachel, Marjo, Nassim, Souad, Adriano, Marine, Firoz, Emmanuelle. J'ai aussi une pensée très chaleureuse pour les gens qui nous ont soutenues lors de l'angoisse et le désespoir après le décès de Mathias: Manie, MarieLili, Marjo, Erwann, Sarah, JoannieF, Rachel, Eva, Charline et Julien; je remercie énormément l'appui infini de Renée, Iften, Pato, Vincent, JB et Isa. Paola: tu amor, tu paciencia y confianza en mi han sido mi motor todos estas ano. Gracias por haber compartido esta aventura. Gracias por el milagro de la vida encarnado en Avril, Mathias, Sophia y Naikoa. Je tiens aussi à remercier mes parents, Armando y Carmen Luz, qui m'ont encouragé toujours à repousser mes limites. Gracias por los esfuerzos y sacrificios, por el amor y ejemplo. Merci à ma sœur Helga qui tout en étant loin me surveille et continue de croire en moi. Gracias mi hermanita por esos anos de infancia y juventud peifectos, te adora. Merci aux amis de la Colombie, avec qui j'ai partagé ces années inoubliables à Santa Marta. Merci à toute la famille et ma belle famille pour les encouragements, l'appui et leur accompagnement dans la distance. xi RÉSUMÉ L 'introduction d'espèces non indigènes de dinoflagellés via le transport maritime représente un risque pour les écosystèmes marins et d'eaux douces du Canada, autant du point de vue de leur biodiversité que de l'économie du pays (e.g. la problématique de la moule zébrée dans les Grands Lacs). Ailleurs dans le monde, des études récentes ont mis en lumière l'influence de vecteurs tels que l'eau et les sédiments de ballast, les routes utilisées par les navires ainsi que les méthodes d 'échange d'eau de ballast sur les introductions d 'espèces non indigènes. Au Canada, le Réseau de recherche du CRNSG Canadian Aquatic Invasive Species Network (CAISN) en partenariat avec Pêches et Océans Canada et Transport Canada fut mis sur pied en 2006 pour explorer les principaux vecteurs de transport des organismes envahissants et les facteurs influençant leur succès d 'établissement afin de développer des modèles de risques pour les eaux canadiennes. Dans le cadre de ce réseau , le but du présent travail est de mieux comprendre le rôle des vecteurs, les patrons d'invasion selon la région et l'influence des différentes méthodes d 'échange de l'eau de ballast, dans l'introduction des espèces non indigènes incluant les espèces nuisibles ou toxiques de dinoflagellés au Canada. Cette thèse se concentre sur la présence d'espèces non indigènes de dinoflagellés dans l'eau (formes végétatives) et les sédiments (formes de résistance) de ballast des navires commerciaux qui visitent les côtes est et ouest du Canada et la région des Grands Lacs. De plus, elle fait le lien avec les facteurs antérieurement nommés ainsi que la durée des voyages et le volume d'eau et de sédiments dans les réservoirs à l'anivée des navires. Le corps de la thèse comporte trois chapitres dont les objectifs, méthodes et principaux résultats sont soulignés dans les lignes qui suivent. L'objectif du premier chapitre est d'examiner la présence et l'abondance des espèces non indigènes et nuisibles ou toxiques de dinoflagellés dans les sédiments des navires visitant la côte est du Canada. L'étude se concentre plus spécifiquement sur l'influence des échanges d'eau de ballast, le type de navire et l'âge de l'eau sur la présence de kystes de dinoflagellés non indigènes. Les échantillons de sédiment proviennent de 65 navires et les espèces de kystes de dinoflagellés contenues ont été dénombrées à l'aide d'un microscope Xll inversé. Les résultats confirment la présence de kystes de dinoflagellés non indigènes dans les sédiments de ballast. De plus, certains d'entre eux ont été observés avec du contenu cellulaire (donc potentiellement viables) et des abondances importantes, notamment dans les navires en provenance du nord de la côte est des États-Unis qui, selon la législation canadienne en cours, ne sont pas obligés de faire un échange d'eau de ballast. Ce chapitre a été publié dans la revue Aquatic Invasions. L'objectif du deuxième chapitre est de comparer l'introduction de kystes de dinoflagellés d'espèces non indigènes et nuisibles dans les sédiments de ballast des navires qui visitent la côte est, la côte ouest et les Grands Lacs du Canada.
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