THE OLIVE-BACKED THRUSH. 



( Turdus ustulatus swainsonii.) 



All the notes of the forest-throng, 

 Flute, reed and string, are in his song. 



—Edward R. Sill, "The Thrush." 



The summer home of the Olive- 

 backed Thrush is in the evergreen for- 

 ests of the mountainous regions of the 

 northeastern and northwestern portions 

 of the United States, and quite through- 

 out tne British possessions. During its 

 migrations it is more common east of 

 the Rocky Mountains, and as a strag- 

 gler it is also found on the Pacific coast. 

 Its winter home is in the southern 

 United States, Cuba, Central and South 

 America. 



A denizen of the forest and having a 

 shy and retiring disposition, this Thrush 

 spends most of its time in the trees and 

 larger undergrowth. Only during its 

 migrations does it descend to the ground. 

 In the presence of an intruder it will 

 retreat to the higher branches of the 

 trees, where it is hidden by the foliage. 

 When frightened it not infrequently 

 hides behind the limb of a tree, and some- 

 times it will set perfectly quiet with 

 its back toward the intruder, seemingly 

 trusting to its somber color for protec- 

 tion. It is so shy and retiring in its 

 habits that it is not easily observed and 

 quite usuallv remains unnoticed unless 

 its characteristic notes are heard. "In 

 late September or early October their 

 loud, metallic call-like notes may be 

 recognized overhead at night, and dur- 

 ing the day the birds themselves may be 

 found on the edges of the woods or along 

 tangled hedgerows, associated with spar- 

 rows and other migrants." 



Like the hermit thrush, the Olive- 

 backed species is often called Swamp 

 Robin. Many observers find a strong 

 resemblance both in song and habits be- 

 tween the two species ; the chief differ- 

 ence is that the former frequents the 

 underbrush and the Utter is more com- 

 monly seen among the branches of trees. 

 However, Dr. Bryant observes : "Its 

 notes differ entirely from that of the 

 hermit thrush, and the birds also differ 

 verv much in their habits." While the 



hermit seeks its food low down or on 

 the ground, the Olive-backed will not 

 infrequently launch forth from its perch 

 on a tree top in pursuit of passing in- 

 sects, which it catches while on the wing 

 with the dexterity of a flycatcher. 



To some the song of the Olive-backed 

 Thrush sounds like an inferior rendering 

 of that of the Wood Thrush. "The 

 tones are not nearly so loud, liquid and 

 penetrating." Mr. Langille, who has 

 studied the habits of these thrushes in a 

 locality that both frequent, says: "In 

 this locality the similarity of its song to 

 that of the wood thrush can be well 

 studied, for they both sing very com- 

 monly in closely adjoining haunts, and 

 were it not for the greater brilliancy and 

 marvelous expression of sentiment in the 

 performance of the latter, the Olive-back 

 would rank as no mean artist." In its 

 summer home, where, from a com- 

 manding position at the very top of some 

 tree, it pours forth its "ringing song," its 

 notes are truly inspiring. In the words 

 of Mr. Dwight, "The effect of its loud 

 and beautiful song is much enhanced by 

 the evening hush in which it is most 

 often heard. It lacks the leisurely 

 sweetness of the hermit thrush's out- 

 pourings, nor is there pause ; but in a 

 lower key and with greater energy it 

 bubbles on rapidly to a close rather than 

 fading out with the soft melody of its 

 renowned rival." 



The neat home of the Olive-backed 

 Thrush consists of coarse grass, leaves, 

 small roots and fibrous shreds of bark, 

 firmlv woven into a solid mass. In the 

 Arctic regions moss is largely used in 

 the walls of the nest. The lining usually 

 consists of fine grass and rootlets and 

 fragments of leaves. The nest is gen- 

 erally placed in bushes or small trees at 

 a height of from five to eight feet from 

 the ground. Wooded banks of streams 

 and lakes are the most favored localities 

 for the nesting of this thrush. 



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