. [Articles about birds from National geographic magazine]. Birds. CROWS, MAGPIES, AND JAYS 53. From E. R. Kalmbach WHAT IT TAKES TO RAISE A CROW The nestling crow requires about lO ounces of food per day, or about 13^^ pounds for its nestling life of three weeks. At the end of that time it will weigh about a pound. During this period it will have eaten two and a quarter times its own weight of May beetles. The grasshoppers it has eaten would, if combined, form a mammoth insect about twice the size of the bird. Wild birds and poultry would each form a mass about a fifth of the crow's weight an
. [Articles about birds from National geographic magazine]. Birds. CROWS, MAGPIES, AND JAYS 53. From E. R. Kalmbach WHAT IT TAKES TO RAISE A CROW The nestling crow requires about lO ounces of food per day, or about 13^^ pounds for its nestling life of three weeks. At the end of that time it will weigh about a pound. During this period it will have eaten two and a quarter times its own weight of May beetles. The grasshoppers it has eaten would, if combined, form a mammoth insect about twice the size of the bird. Wild birds and poultry would each form a mass about a fifth of the crow's weight and corn about one and one-half times its mass. Here are pictured a fully fledged young crow and its principal food items. These include small mammals, spiders, caterpillars. May beetles, poultry, wild birds, miscellaneous beetles, carrion, corn, amphibians, crustaceans, and grasshoppers. These are all drawn to a scale that approximately represents the aggregate mass of the different items consumed during the nestling life, compared with the bird that ate them. noticed that ravens were frequently pres- ent. In August, 1924,1 counted more than 60 at one time. They would sail out from over the forest and gradually descend to the short grass, there to walk sedately about and feed upon the numerous grass- hoppers of the valley. Very rarely one sees so many ravens together. Usually they are found only in family groups, composed of the parents and their offspring. When the young have attained the necessary age and experience to shift for themselves, they wander off, but their elders remain together even until the snow begins to melt and the call comes to repair again the old nest. RAVENS SEEK LOETY NESTING SITES Although sometimes ravens use trees as nesting sites, their usual selection is a high, beetling cliff. Here, often hundreds of feet above the sea, or above the floor of. Please note that these images are extracted from scanned page images that may have been digitally enhanced f
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