. Bulletin. Les insectes ; les insectes nuisibles ; entomologie ; insectes ; les insectes nuisibles ; l'entomologie. Divers ennemis. 135. Les oiseaux. Nombre d'immenses oiseaux dévorent le grain du printemps-APHIS. Miss Margaret Morse, de l'Université Clark, a eu la gentillesse de faire quelques expériences pour nous à l'alimentation des cailles de Toxoptera. Elle a appris qu'ils sont très friands de l'aphidids et estime qu'environ 5 000 ont été mangé par un Toxoptera caille unique en un jour, la préférence affichée pour ceux qui étaient non parasités. M. W. L., Human Life by Sylvester Graham de la Commission biologique du ministère de l'Agriculture des États-Unis,

• Contributeur: Library Book Collection / Alamy Banque D'Images
• ID de l’image: RGTXDE
• Taille du fichier: 7,1 MB (329,9 KB Téléchargement compressé)
• Autorisations: Modèle - non | Propriété - non
• Dimensions: 1253 x 1994 px | 21,2 x 33,8 cm | 8,4 x 13,3 inches | 150dpi

Informations supplémentaires

Cette image appartient au domaine public, ce qui signifie que le droit d’auteur a expiré ou que le titulaire du droit d’auteur a renoncé à ses droits. Les frais facturés par Alamy couvrent l’accès à la copie haute résolution de l’image.

Cette image peut avoir des imperfections car il s’agit d’une image historique ou de reportage.

. Bulletin. Insects; Insect pests; Entomology; Insects; Insect pests; Entomology. MISCELLANEOUS ENEMIES. 135. Birds. Birds devour immense numbers of the spring grain-aphis. Miss Margaret Morse, of Clark University, has been kind enough to conduct some experiments for us in feeding Toxoptera to quail. She has learned that they are very fond of the aphidids and estimates that about 5, 000 individual Toxoptera were eaten by a single quail in one day, preference being shown for those that were unparasitized. Mr. W. L. McAtee, of the Biological Survey of the United States Department of Agriculture, made some special studies of the aphis- eating habits of some of our birds in March-April, 1909, at Winston- Salem, N. C, at the time Toxoptera was so destructive in that vicinity. He states that in a wheat field of about 100 acres there were over 3, 000 birds present daily; sometimes the number ran as high as 8, 000 to 9, 000. So large a number of birds would be found in the fields only during migration, and even at that time the presence of so many indi- cates that they were attracted to the fields by the abundant food. In so far as could be ascer- tained, about nine-tenths of the birds were feed- ing upon aphidids (including Toxoptera graminum, Macrosiphum granaria, and Aphis avense), some taking as many as 180 at a single meal. These aphidids are very small, soft-bodied insects and many meals would be required by a bird in a single day to satisfy its hunger. The average number per meal was at least 50, and we may assume that 6 times this number were taken per day. On this basis the number of aphidids de- stroyed by birds on the farm daily during the migration season is 90, 000. Below is a partial list of the species Mr. McAtee found devouring Toxoptera at Winston-Salem. A complete list can not be given at this time, since his studies are not yet finished; many species will undoubtedly be added. Goldfinch (Astragalinus tristis). Vesper sparrow (Pooecetes gramineus). Savanna spar

Recherche dans la banque de photos par tags

• bookcentury1900
• bookdecade1900
• booksubje
• livresubjectentomologie