. Bulletin du Ministère de l'Agriculture des États-Unis. L'agriculture ; l'Agriculture. BULLETIN n° 1196 du ministère. Washington, D. C., janvier 1924 L'ALIMENTATION ET DES RELATIONS ÉCONOMIQUES DE GRÈBES EN AMÉRIQUE DU NORD. Par Aijexander Wetmoee, biologiste adjoint, Division des enquêtes biologiques- tions, Bureau de la Commission biologique.1- Contenu. La page. Introduction 1 La distribution et les habitudes des grèbes- 1 Description 2 nids, oeufs, et les jeunes des relations économiques 2 3 4 L'alimentation en l'état protégé 4 page. Grèbe élégant . 5 grèbe Holboell 7 Grèbe esclavon Grèbe 10 15 18 mexicain grebe Grèbe à bec bigarré 19 INTRODUCTION. Un kn

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. Bulletin of the U.S. Department of Agriculture. Agriculture; Agriculture. DEPARTMENT BULLETIN No. 1196. Washington, D. C. January, 1924 FOOD AND ECONOMIC RELATIONS OF NORTH AMERICAN GREBES. By Aijexander Wetmoee, Assistant Biologist, Division of Biological Investiga- tions, Bureau of Biological Survey.1- CONTENTS. Page. Introduction 1 Distribution and habits of grebes- 1 Description 2 Nests, eggs, and young 2 Economic relations 3 Feather eating 4 Protected status 4 Page. Western grebe . 5 Holboell grebe 7 Horned grebe 10 Eared grebe 15 Mexican grebe 18 Pied-billed grebe 19 INTRODUCTION. A knowledge of the feeding habits and general economic status of the species of grebes inhabiting the different sections of the United States is of importance in connection with the relations of these birds to the supply of food fishes. Living in ponds, lakes, and water- courses, grebes have at times been suspected of being seriously detri- mental to the continuance of certain valuable fishes. That this suspicion is without actual foundation in fact has been ascertained in the investigations reported upon in this bulletin. DISTRIBUTION AND HABITS OF GREBES. Six species of grebes are found in North America north of the Isthmus of Panama, all of them ranging within the limits of the United States. These birds breed in the interior, but during their migrations are found on salt water along our coasts as well as on open ponds and streams throughout the country. Their almost supernatural powers of diving to escape a shot are common knowl- edge among hunters, from the boy armed with a small-bore rifle to Prepared by the author when a member of the present Division of Food Habits Re- tearch. NOTE.—This bulletin presents a detailed study of the food and feeding habits of th< Hix species of grei, cS thai occur in (lie United States. II will serve as an index (o the economic status of the i birds, and will be useful to naturalists, sportsmen, , conservation- l*ts, i Interested In waterfow

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