Its breeding range extends from Newfoundland to central Alaska, and from Nova Scotia to British Columbia, which includes nearly all of Canada. It migrates through most of the United States, principally through the Mississippi River Basin, and winters in Mexico and possibly South America.
Only a few nesting data are referable to the Newfoundland yellow warbler. Henry Mousley (1926), at Hatley, Quebec, saw a female yellow warbler leaving a large cedar hedge, and says: “Proceeding to the spot from which she came out, I found the nest, which, unlike the usual run of nests of this species, was heavily lined with feathers, instead of plant down. * * * It was nine feet above the ground, in the forks of a small cedar tree.”
Roderick MacFarlane (1908) found this warbler abundant in northern Mackenzie, where the nests were “placed on dwarf willows and small scrub pine at a height of a few feet above the ground.” Dr. E. W. Nelson (1887) writes:
This is, perhaps, the most abundant warbler throughout Alaska. It is found everywhere in the wooded interior, on the bushy borders of the water-courses, or frequenting the scattered clumps of stunted alders on the shores of Bering Sea, and the coast of the Arctic about Kotzebue Sound. * * * It breeds to the shores of the Arctic Ocean wherever it can find a willow or alder patch wherein to build its nest and shelter its young. * * * In fall, from the last of July to towards the last of August, they come about the houses and native villages to feast on the fare they find provided abundantly in those localities, until, a little later in the season, a few chilling storms send them trooping away with others of their kind to far distant winter quarters.
Dr. Herbert Brandt (1943) writes:
The Newfoundland Yellow Warbler was not observed about Hooper Bay, but as soon as I reached the willows near the mouth of the Yukon River I found it common, and also of like distribution at the other stops that I made on the river as far up as Mountain Village. * * *
The nest of the Newfoundland Yellow Warbler in the Yukon delta is placed usually in a small willow from two to six feet above the ground. The foliage in early July is but partly unfolded, for the alders are yet in their golden curls and the willows in their silver catkins, so the nest is rather conspicuous.
The bird chooses a pronged fork usually with not more than three or four shoots, and in this form constructs its beautiful, trim nest, which is made of plant down and inner bark shreds, all circularly woven and firmly rimmed.
Baird, Brewer, and Ridgway (1874) say: “The notes of Mr. Kennicott and the memoranda of Messrs. McFarlane, Ross, and Lockhart attest the extreme abundance of this species in the farthest Arctic regions. In nearly every instance the nests were placed in willows from two to five feet from the ground, and near water. In one instance Mr. Ross found the eggs of this species in the nest of Turdus swainsoni, which had either been deserted or the parent killed, as the eggs were in it, and would probably have been hatched by the Warbler with her own.”