270 
It may not always be separable in life from the former except by geographical probability, 
but is best distinguished from the latter by its general warm orange or yellow tone instead 
of cold, dull green. The voices of the Orioles are always distinctive, a rich contralto whistle 
with numerous musical themes, but the voice of Bullock’s Oriole is not so fine nor so full 
as that of the Baltimore. 
Nesting. A deep bag of woven fibres, plant down, hairs, and string hanging from the 
tips of long branches. Similar to that of the Baltimore Oriole. 
Distribution. Western North America. In Canada, southern British Columbia, 
chiefly east of the Coast range, and extreme southern Alberta and adjoining 
Saskatchewan. 
Very similar in habits and general status to the Baltimore Oriole, but 
rather less musically pleasing and less conspicuous than that species. 
Economic Status. Food analysis of stomach contents ’n fruit districts 
shows that about 79 per cent of the food of Bullock’s Oriole is animal matter 
and 21 vegetable. Lepidoptera, in the form of moths, pupa*, and cater- 
pillars, are the largest item, but scales are a standard item of diet. Beetles, 
almost all harmful species, bulk largely in the food supply. Nine per cent of 
the vegetable food is fruit, largely cultivated varieties where they can be 
obtained. With its good record as a fruit-pest destroyer, only the prejudiced 
or particularly unfortunate sufferer will fail to admit that it is most bene- 
ficial. 
509. Rusty Blackbird, rusty grackle. Euphagus carolinus. L, 9-55. Very like 
Brewer’s Blackbird (See Plate XLIX B). About the size of the Red-winged and Brewer’s 
Blackbird. All black or all black washed with rusty. Much larger than the Cowbird, 
but considerably smaller than the Bronzed Graekle. Eyes, straw-coloured in both sexes. 
Distinctions. With size and plain black coloration, easily confused with Brewer’s 
Blackbird, but the spring male has green instead of purple reflections on the head. In 
autumn, the Rusty Blackbird is strongly overwashed with ruddy rusty above, solid and 
complete on crown; and rusty ochre below, strongest on superciliary line and throat. 
Females are solid smoky black, slightly darker than the female Brewer's, and usually with 
faint traces of rusty on breast or back. The throat never lightens to ashy. On the average, 
the bill is slightly longer and more slender. Some specimens are very difficult to 
separate. 
Field Marks. Medium size, and solid black coloration, or black with much rusty 
overwash and decided ochreish superciliary line. Eyes in both sexes pale straw-yellow. 
Male recognized from Brewer’s by green instead of purple reflections about head; the 
female by having pale, straw-coloured eyes. 
Nesting. A bulky structure in coniferous trees or on the ground. 
Distribviion. Eastern and northern North America. In Canada, across the continent, 
west to the mountains, breeding from northern tree limit to the edges of the prairies. 
Occasional in southern British Columbia in migration, where it seems to be increasing of 
late years. This is only a migrant throughout most of the breeding range of Brewer’s 
Blackbird. 
The Kusty Blackbird comes in great numbers in spring and autumn, 
joining and forming a considerable part of the large flocks of mixed Black- 
birds that are seen about the fields and marshes. The name Graekle 
which is commonly applied to the two yellow (nearly white) -eyed Black- 
birds is doubtlessly derived from the sound of their harsh, crackling notes. 
Economic Status. Though the Rusty Blackbird is fairly omnivorous, 
it shows a decided preference for animal, over vegetable, food. The animal 
matter amounts to 53 per cent, very little of which is of sources beneficial 
to man. Grain constitutes a remarkably small percentage of the whole. 
As the bird is mostly a migrant through cultivated sections, coming in 
numbers only after the harvest, and haunting stubble principally, most of 
the grain taken is necessarily waste. 
