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La Sélection Des Proies Chez Un Canard De Mer Molluscivore: Implications Pour Les Habitats Naturels Et Les Sites D'aquaculture

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La Sélection Des Proies Chez Un Canard De Mer Molluscivore: Implications Pour Les Habitats Naturels Et Les Sites D'aquaculture UNIVERSITÉ DU QUÉBEC À RIMOUSKI LA SÉLECTION DES PROIES CHEZ UN CANARD DE MER MOLLUSCIVORE: IMPLICATIONS POUR LES HABITATS NATURELS ET LES SITES D'AQUACULTURE THESE PRÉSENTÉE COMME EXIGENCE PARTIELLE DU DOCTORAT EN BIOLOGIE EXTENSIONNÉ DE L'UNIVERSITÉ DU QUÉBEC À MONTRÉAL PAR ÉLISABETH VARENNES JANVIER 2016 UNIVERSITÉ DU QUÉBEC À MONTRÉAL Service des bibliothèques Avertissement La diffusion 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 travail de recherche de cycles supérieurs (SDU-522 - Rév.Ol-2006). Cette autorisation stipule que «conformément à l'article 11 du Règlement no 8 des études de cycles supérieurs, [l'auteur] concède à l'Université du Québec à Montréal 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 Montréal à reproduire, diffuser, prêter, distribuer ou vendre des copies de [son] travail de recherche à des fms 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.» Trouver le courage de réaliser ses rêves (Elisabeth Varennes) A V ANT -PROPOS Ce projet de recherche, et notamment le dernier chapitre de cette thèse sur le test des filets d'exclusion, a été initié grâce à un partenariat international entre plusieurs institutions de recherche. Ce partenariat a été mis en place grâce à une collaboration entre Sveinn A. Hanssen, chercheur au « Norwegian Institute for Nature Research » (NINA) ; John C. Bonardelli, conseiller technique de Shellfish Solutions Inc. en Norvège ; et Magella Guillemette, professeur-chercheur à l'UQAR. En plus du soutient financier du Conseil Norvégien de la Recherche pour ce projet, nos collègues norvégiens ont participés comme co-auteurs à chacun de mes chapitres, me permettant de les améliorer grâce à leur expertise variée et complémentaire. Je tiens donc à remercier mes co-auteurs, Sveinn et John, ainsi que mon directeur de thèse, Magella, pour leurs soutiens, idées et enseignements qui m'ont aidé à faire cette thèse. Je remercie aussi les membres de mon jury d'évaluation pour le temps consacré à lire et commenter cette thèse, et avoir ainsi permit l'amélioration de ce travail : Dan Esler (USGS - Alaska Science Center), William Vickery (UQAM) et Réjean Tremblay (UQAR - ISMER). De plus, ce projet est un bel exemple de collaboration inter-institutionnelles car il n'aurait pas était possible sans l'implication indispensable de Pêches et Océans Canada, via l'Institut Maurice Lamontagne (IML) et le chercheur Chris Mc Kindsey. J'ai eu la chance d'avoir accès à des installations uniques en Amérique du Nord, ainsi qu'à une multitude de matériel et aide technique de la part de plusieurs employés de l'IML. Je souhaite donc remercier de nombreuses personnes de cette institution, notamment Chris et toute son équipe, François Tremblay, Bernard Chenard, Réal Gagnon, Tanya Hanssen, Marcel Fréchette et Linda Girard, Yvan Lambert, Richard Larocque, Denis Chabot, Hélène Dionne, Sylvie Brulotte et beaucoup d'autres. Je tiens aussi à souligner, qu 'en plus de la qualité de recherche émanent de l' IML, les v personnes travaillant dans cette institution permettent d'en faire un cadre de travail très agréable où j 'ai pu m'épanouir et apprendre beaucoup sur le milieu marin en général. Je garderais donc un souvenir très positif de mon passage par l'IML, que j 'ai souvent qualifié de deuxième maison ! Je tiens aussi à remercier plusieurs personnes affiliées à l' UQAR et l' ISMER au moment des faits pour leur soutien technique notamment Réjean Tremblay, Samantha Richman, Yves Lemay, Jonathan Coudé, Alain Caron, Danie Massé, et plusieurs chercheurs, notamment ceux ayant fait partie de mes différents comités d' évaluation. J'adresse un grand merci aux étudiants que j'ai eu la chance de superviser et qui ont grandement aidé dans mes expériences : Frankie, Marie-Christine, Mireille et Hughes. Je vous souhaite un bel avenir dans le domaine professionnel de votre choix ! Je remercie aussi le regroupement Ressource Aquatique Québec pour les différentes bourses octroyées qui m'ont permis de poursuivre mon projet et de participer à plusieurs conférences pour présenter mes résultats. Ce regroupement, en plus de fournir de l'aide fmancière, offre aussi une belle voie au réseautage professionnel pour ses membres étudiants. Je remercie d'autres organismes qui ont participé au financement de certaines de mes conférences internationales, tels que la SFECA, Québec Océan, et les comités du Sea Duck Joint Venture 2011, de l'ISBE 2014 et de la NACE 2015. Enfin, je remercie Boreas pour ses bourses de soutien aux études et à la publication et l'UQAR pour ses bourses de mobilité. J'adresse aussi un grand merci aux différents aquaculteurs qui m'ont aidé au cours de ce projet, en me fournissant des moules ou en partageant leurs précieux conseils. Grâce à eux j 'ai pu en apprendre beaucoup sur cette industrie de la mer responsable et durable. Je remercie particulièrement Stéphane Morissette (Les Moules Cascapédia ltée), Jacques Dufresne (Les Moules de Gaspé) et Carter Newell (Pemaquid Mussel Farms). L'ordre des remerciements ne correspond pas forcément à l'importance de l' implication, car je souhaite maintenant remercier mes nombreux proches, famille et amis, qui m'ont tous aidé, à leur manière, à avancer dans cette aventure Vl professionnelle! Tout d'abord, je remercie de tout mon cœur mon mari, Sébastien Brennan-Bergeron, qui a toujours été là pour m'accompagner et me soutenir, tel un phare dans la nuit. Je remercie aussi ma famille en France, qui a accepté et même encouragé mon départ si loin, et qui malgré la distance ont toujours été présents dans mon aventure. J'adresse un merci particulier et plein d'émotions à mon frère, Eric, mon père, Gilles et mon oncle, Dominique. Je remercie aussi ma « belle » famille, qui m'a permit d'avoir une famille ici aussi, et particulièrement mon beau-frère Mathieu, ma belle-mère Sharron et mon beau-père Denis, qui, je sais, sont aussi fières de moi que ma famille de sang! Étant donné que je considère mes amis comme de la famille, je remercie plusieurs amis français qui, malgré l'éloignement, ont su me soutenir dans mes différentes aventures : Géraldine, Caroline B. , Caroline V., Momo, Claire, Isabelle, Régis et Violaine, Sarah, Clarisse, Blandine, et plusieurs autres. Je remercie aussi mes « compagnons de galère », amis de Rimouski, dont la plupart savent ce que ça représente de faire un Doctorat, et qui ont donc été une compagnie de choix pour combattre certains moments de morosité: Anouck, Marion, Adriana, Nicolas, Cyril, Gaëlle, Magali, Kim, Corinne et Simon, Stéphane et Émilie, et mes amis de la voile dont particulièrement Michael et Becca Scarratt et leur voilier Noctiluca. J'ai aussi une petite pensée pour mes oiseaux qui rn ' ont tenue occupée pendant plusieurs années et qui ont su me rappeler que, finalement, c'était eux qui décidaient quand ils voulaient travailler ou pas ! Je termine cet avant-propos par une pensée très émue à deux personnes qui ont été très importantes dans ma vie et qui rn ' ont grandement aidé à devenir la femme accomplie que je suis maintenant: ma maman, Odile, et ma tante, Claude. Vous me manquez beaucoup et vous garderez toujours une place importante dans mon cœur ! TABLE DES MATIÈRES AVANT-PROPOS .............................. ... ..................... .... ... ................................................... .iv LISTE DES FIGURES .... ..................... ... .................... ..................... ... ..... ............................. xi LISTE DES TABLEAUX .. .... ........................................................................... ... .. ............. xiii RÉSUMÉ ... ........ ... ...................... .......... ... .. ...... ... ........................................................ .......... xv ABSTRACT ............................ ...... ... ..... .. .. .. ....................... ................. ... ............................ xvii INTRODUCTION GÉNÉRALE ..................... ........... .... ... .... .... ................................ ............. 1 REPONSE FONCTIONNELLE ............................................................................... ..................... 3 S ELECTION DE PROIES ........................................ ...................................... .............................. 8 LA PREDATION SUR LES ORGANISMES BENTHIQUES ... .................. ...................... .. ................ 12 LA DEPREDATION DES CANARDS DE MER DANS LES AQUACULTURES .................. ................. 20 OBJECTIFS DE LA THESE ....................................... .. ..................................... ......................... 28 CHAPITRE 1 FUNCTIONAL RESPONSE CURVES OF A VIAN MOLLUSCIVORES: HIGH INTAKE RATES MAINTAINED EVEN AT LOW PREY DENSITY .. ......... ........ 32 1.1 INTRODUCTION ............................................ ............................................. .................. 35 1.2 METHODS ..................................................................... ....... ......................................
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