Page:Bird-lore Vol 03.djvu/153

 Many Crows make the same journey by straggling flight over favorite routes from and to their roosts in willows in the tule ground and the Yellow-billed Magpie, now becoming rare, has a similar habit of flight and purpose.

During August there is a southward movement of the summer resi- dents, quite imperceptible, but so effectual that by September i but few of them remain. At the same time some of our resident species are re- inforced by individuals which breed in Nevada or north of us.

In the first week of September Gambel's Goose and a few other water birds which breed in cold climates begin to arrive, but not until the 20th is there a marked inflow of winter sojourners. Then the Inter- mediate Sparrow, Western Savanna Sparrow and American Pipit may be confidently sought. Four or five days later the Golden -crowned Sparrow arrives.

These birds are as constant in date of arrival and departure as any that visit us and being abundant are easily traced. The following sometimes arrive as early as September 20 : Short -eared Owl, Sharp-shinned Hawk and Audubon's Warbler ; from 25-30, Town- send's Sparrow, Lincoln's Sparrow, Mountain Song Sparrow and Junco. In the March -April Bird -Lore I intended to name the Western Savanna Sparrow as leaving about May i instead of Townsend's Sparrow. Several confusing forms of Song Sparrows, Juncos and Horned Larks visit us in winter. SUGGESTIONS FOR THE SEASON'S STUDY Nesting. — What birds are found nesting in August? Are they rearing first or sub- sequent broods ? Among the birds breeding in your vicinity which species raise one brood? Which two? Which three broods? Have you positive evidence that any species succeeds in rearing three broods? Song. — Note the dates when various birds are last heard to sing. What young birds are heard singing in August ? What evidences are observed of a second song period after the molt is concluded ? The Molt. — The molt cannot be studied to advantage in living wild birds, but vari- ous evidences of it may be observed at this season among young birds changing their nest- ling for the first winter plumage, and with such adult birds as the male Bobolink or Scarlet Tanager when losing their bright breeding dress for a dull winter costume. Migration. — Note the first signs of migration in the flocking of birds and the return nightly to a given roost; good examples are Swallows, Red-winged Blackbirds and Robins. The roosting habits of these birds form most interesting studies. When are the first migrants from the north observed? Which of the birds nesting in your vicinity is the first to go south, that is, to disappear? What is the northern limit of the breeding range of these species? Do you observe any connection between their breeding range and the date of their departure? During the first half of August some previously common birds will be very rare — Baltimore Orioles, for instance — but in the latter half they will again become common. Are the late August birds newcomers from the North or our summer resident birds, who in early August were molting? Among migrants from the north are the first comers young or old birds? At the time of the full moon in September,