1320 
REPORT OF THE CHIEF OF ENGINEERS. 
43. Circus cyaneus L., var. liudsonius L.—Marsh Hawk. 
Present in the meadows through the mountains, and though not nearly so numerous 
as below, it is still common. 
44. Butco borealis (Gmel.), var. calurus Cass.—Western Red-tailed Hawk. 
Abundant. With this hawk, as is the case with most of the species, a change of hab¬ 
itat is made necessary in the late fall, when snow and severe leather cause the disap¬ 
pearance of the small mammals, reptiles, and other game upon which it preys. They 
then move down into the valleys and remain about the lakes, where not only are found 
an abundance of water fowl, but where the marshes afford them an unfailing supply ot 
certain small rodents through the season. 
45. Archibuleo lagopus (Bruno.), var. sancti-johannis. —Rough-legged Buzzard. 
Very numerous. In early November, in a meadow of considerable size not far from 
Lake Tahoe, I found that scores of this hawk had congregated. From one to half i 
dozen were visible at any hour of the day, sweeping with heavy wing over the surface 
of the turfy ground, and now and then dropping with almost certain aim upon one of 
the small Meadow Rats (Arvicola riparius) whose excavations honeycombed the ground 
in all directions, and whose immense numbers accounted for the unusual abundance of 
the hawks at this one locality. 
46. AquiJa chrysaetus (L.)—Golden Eagle. 
Apparently rather more numerous in this region than the succeeding bird. 
47. 1Talmtus lencocephalus (L.)—Bald Eagle. 
Rather rare. In fact eagles are rarely abundant in any portion of the west which 
I have visited, and the sight of one is an event of sufficiently unusual occurrence to 
attract the attention and elicit comment from the most unobservant of a party. The 
white-headed is much more numerous as an inhabitant of either coast than as a bird 
of the interior. 
TETRAONID/E. 
43. Canace obscurus (Say.)—Dusky Grouse. 
The whole pine-timbered region lying along the eastern slope of the Sierras west 
of the Carson Valley, was formerly the home of very great numbers of this line bird. 
Some of the stories told by the early settlers of its abundance are almost incredible. 
The sound of the woodman’s axe is followed by the almost complete abandonment of 
a locality, and chiefly from this cause and from the persecution they have been subjected 
to at the hands of the settlers and the Indians, the localities are very few where the 
grouse still exist in abundance. The steep sides of many of the deep canons have 
proved inaccessible to the lumberman, aod still retain the primeval growth of forest. 
Here the grouse still maintain their foot-hold, and will continue to do so long after the 
surrounding country has been swept bare of woods. 
PERDICID.E. 
49. Oreortyx pictus (Dough)—Plumed Partridge; Mountain Quail. 
This beautiful bird ranges from the coast across the mountains, and is found along 
the eastern slope, where, at an elevation of about 6,000 feet, it is quite abundant. As 
noticed before, it reaches the lower foot-hills, but in very much diminished numbers. 
Usually a resident bird wherever found; the only effect winter has upon their rauge 
is to cause'them to abandon the higher elevations occupied in summer, and to appear 
farther down upon the mountain-sides. 
The mountains of this whole region lying about Lake Tahoe seem to be entirely 
abandoned by the species in winter, and a very complete migration takes place during 
the late fall. The flocks then pass not to the South, but westward, and winter upon 
the western slopes of the mountains, descending to a greater or less distance toward 
the foot-hills, according to the depth of snow, the severity of the weather, &c. Such 
at least is the explanation offered by the hunters and residents for their disappearance 
about November from this section, where earlier they are very abundant, and which 
I have every reason to believe is the true one. Those living in summer on the low foot¬ 
hills about Carson remain to winter. But those whose summer habitat is higher up. 
in the mountains proper thus make a short migration to a region better adapted to 
their wants. 
The snow upon the eastern slope falls to a great depth, and the winter is very severe, 
much more so than on the western side—facts which appear to have been thoroughly 
acquired by experience by these birds, till the habit of migration, in anticipation of 
winter lias become a flxed and constant one. 
