BIRDS OF MINNESOTA 439 
TURDUS USTULATUS SWAINSONILT (Casanis). (758a. ) 
OLIVE-BACKED THRUSH. 
The uniform shade of the upper parts, somewhat emphasized 
on the rump and tail, distinguishes this species amongst the 
Thrushes. 
Arriving here late in April, or in the early part of May, it is 
abundant for a short time, but moves northward then, only a 
few comparatively remaining to breed, and those principally 
in the northern counties of the State. Its favorite places for 
nesting here seem to be the edges of heavy timbered tracts, 
which are bordered with brushland, or thickets of oaks. They 
build their nests about the 20th to the 25th of May, on a hori- 
zontal limb, which is usually five to seven feet from the ground. 
It is very compactly built of such material as the locality af- 
fords including strips of bark, leaves, lichens, moss, &c. The 
eggs, usually four or five in number, are light greenish-blue, 
speckled with several shades of reddish-brown. 
The song of this species does honor to its melodious group, 
having about as much variety as those of the other thrushes, 
and more nearly resembles that of the Hermit. For many years 
Swainson’s Thrush was seldom seen except in migration, but 
since the country has been more extensively settled, and fires 
have ceased to destroy the brushlands and timber, it has been 
increasing in the numbers of individuals that remain during 
the summer. I have seldom found it feeding on the ground 
after the manner of most of the same genus but on the trees 
and brush, and unlike any of them, dashing out after insects 
essentially like a warbler or a flycatcher. 
One specimen of this species obtained in July was building a 
new nest, which must be exceptional, for although rearing two 
broods they appear usually to build but one. Perhaps it had 
been molested. The autumnal migration takes place simulta- 
neously with that of most of the other thrushes, except the 
Robin. 
As to their distribution throughout the State during migra- 
tion, there seems to be great uniformity where the conditions 
for its food are present. Lists for May are sent me annually 
from nearly every characteristic section of the survey, and a 
good number for the entire summer. They wander to consider- 
able distance from the forests for food, but only in the thickety, 
brushland localities. 
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