MICHIGAN ACADEMY OF SCIENCE. 
17 
this species remains with us as short a time as any of our summer resi¬ 
dents, just long enough to rear its young and get them safely away. 
it™ -7 e have birds like the Lon gspurs, the Pipits, Rusty Grackles, 
and White-crowned Sparrows, Yellowlegs and Ring-neck Plover, Can¬ 
ada Geese, and many ducks, which are strictly birds of passage or 
what we prefer to call transients, seen only for a few days or weeks 
m spring as they pass from their winter quarters in the south to their 
nesting grounds beyond our northern confines, and again for a few days 
in fall on their return journey accompanied by the young just reared, 
let another group of transients, better called winter visitors, should be 
mentioned which come to us in autumn or winter from the north and 
after spending a longer or shorter time with us again withdraw pole- 
wards; such are the Snowy Owl, Great Northern Shrike, the Pine Gros¬ 
beak and two kinds of Crossbills, together with Redpolls, Snow Bunt¬ 
ings, and the much less common Evening Grosbeak and Bohemian Wax¬ 
wing. 
Thus we have four groups of birds, viz.: 
1st. Residents or Permanent Residents, with ns all the year. 
2d. Summer Residents or Summer Visitors (Breeders)." 
3d. Transients or Birds of Passage. 
4th. Winter Visitors or Winter Residents. 
Not a few of our common birds are residents in one part of the State 
and only summer visitors or even transients in another. For example 
the Snowbird or Junco and the White-throated Sparrow are transients 
m the southern half of the State, but summer residents in the northern 
half; while the Meadowlark and Mourning Dove are only summer visi¬ 
tors m most of the state, but permanent residents in the southernmost 
counties. For present purposes we may almost disregard the so-called 
residents or permanent residents, merely remarking that although sev- 
eial species, including woodpeckers, chickadees, creepers, grouse and 
owls, may be well represented throughout the year in any given locality 
we have little proof that the individuals representing these species are 
the same, and there is every reason to believe that, "with a few excep- 
tions ? every species of North American bird is more or less migratory 
some Part of its range. Apparently the Ruffed Grouse and the 
I lame Chicken are stationary in Michigan wherever found, yet we 
know positively that in Minnesota, Iowa and other trans-Mississippi 
states this last named species makes a well-marked though not very ex¬ 
tensive southward migration in autumn, returning northward however 
so gradually and quietly that it attracts little attention. 
. another instance of migration in the grouse family, and a most 
interesting and extraordinary one, I may mention the fact that in 
eastern Oregon, Richardson’s Grouse has its true home among the 
coniferous forests of the higher mountains from 4,000 to 8,000 feet above 
sea-level, yet each year in March the greater part of these grouse mi "rate 
southward across the Powder River to the sage brush plains and 
willow thickets of the lower and warmer country, where they nest, old 
and young returning northward during July and August to the spruce 
and pine forests of the lofty mountain ranges.* *' 
We may study the main features of migration to best advantage, how- 
* A. W. Anthony, Auk, XX, 1903, pp. 24-27. 
