THRUSHES, ETC.: CHESTNUT-BACKED BLUEBIRD 575 
through the winter at Las Vegas, 6,400 feet (Mitchell); and near Albuquerque 
(Birtwell). Since it was seen February 7, 1904, at Arroyo Seco, 8,000 feet (Surber), 
it had evidently wintered not far to the southward. 
The first spring migrant was noted March 1, 1895, at Halls Peak, 8,000 feet 
(Barber); March 14, 1915, at Chloride (Ligon); and April 3, 1915, at State College 
(Merrill).—W. W. Cooke. 
Nest. —In old woodpecker holes, and also in bird boxes. Eggs: 4 to 6, pale blue. 
Food. —Four-fifths insects, only a small part of which are useful, including 
beetles (among them individuals from about a dozen harmful families), caterpillars, 
grasshoppers, crickets, and a small per cent of bees, bugs, ants, and spiders. Insect 
eggs are also eaten. The vegetable food is mainly wild berries, as elderberry and 
mistletoe [cedar berries in winter (Cockerell)]. The bird is an eminently useful 
species (Beal). 
General Habits. —The Chestnut-backed Bluebird is a bird of 
Transition Zone, being abundant in the open yellow pine country in 
lumbered woods and along roadsides, but in the fall it is also abundant 
in the Upper Sonoran nut pine and juniper country. 
At Glorieta, on the edge of Transition Zone, the first week of July, 
1903, we found a pair feeding young in their nest in the knot hole of a 
cottonwood elbow. In the yellow pines, on September 7, 1904, we 
found them between Tusas River and Hopewell. In the open park and 
yellow pine country of the Jicarilla Apache Reservation, the richly 
colored Chestnut-backs were among our commonest birds. At Lake 
Burford, one was taken September 20, 1904, in beautiful fall plumage, 
and three at Horse Lake, September 23, which had apparently almost 
completed their molt. They were also abundant in similar parts of the 
Gallinas Mountains before the cold snap of October 9, although after 
that, while still fairly common, they were not seen in such large numbers. 
On October 7, they were found in the aspens at about 10,200 feet. 
Two taken, October 9, were apparently in perfect winter plumage. 
They were very common in flocks, early in September, 1906, in Valle 
Santa Rosa and the adjoining valleys and rocky hillsides. Late in 
September they and the Pinyon Jays were the most abundant birds of 
the timbered part of the plateau country crossed between Acoma and 
Old Fort Tularosa, at that time frequenting both yellow pine and nut 
pine and juniper country. 
Chestnut-backs were seen on October 16, 1906, as we were climbing 
the Mogollon grade, and the next day, in Silver Creek gulch. Here, 
numbers that had gathered at sunrise on the sunny side of the cold 
narrow gulch, with friendly companies of juncos, White-crowned 
Sparrows, and Audubon Warblers, were seen eating elderberries. On 
October 18 and 20, they were seen at about 9,000 feet on pine ridges, 
numbers of them on the twentieth. A cold wave and snowstorm 
overtook us then, but on the twenty-third, when the storm was over, a 
