CHESTNUT-SIDED WARBLER 
(Dendroica pensylvanica) 
Range: Breeds mainly in the Transition 
Zone from central Saskatchewan, northwestern 
Manitoba, central Ontario, and Newfoundland 
south to eastern Nebraska, Illinois, Indiana, 
northern Ohio, northern New Jersey, and 
Rhode Island, and south in the Alleghenies to 
Tennessee and South Carolina; winters from 
Guatemala to Panama. 
Since the days *of Wilson, Audubon, and 
Nuttall there is little doubt that the chestnut- 
sided warbler has increased in numbers, and 
within its range it is now one of the commoner 
of the family. Itistrim of form and its colors, 
though not gaudy, have a quiet elegance all 
their own. During the fall migration it shows 
little preference in its hunting grounds, but is 
found with others of its kin in all sorts of 
woodland haunts and in deciduous as well as 
coniferous trees. It frequents open woodland 
tracts in summer and loves to nest in low 
thickets of hazel and barberry In favorable 
localities in Massachusetts I have frequently 
found half a dozen nests in a morning’s search. 
The nests are made of shreds of bark and 
grasses and are put together so loosely and 
carelessly that, in connection with their situa- 
tion, they unmistakably betray their ownership. 
KENTUCKY WARBLER (Oporornis 
formosus) 
(For illustration, see page 93) 
Range: Breeds in Carolinian and Austrori- 
parian Zones from southeastern Nebraska, 
southern Wisconsin, southeastern and south- 
western Pennsylvania, and the Hudson Valley 
south to eastern ‘Texas, Louisiana, Alabama, 
and northern Georgia; winters from Tabasco, 
Campeche, and Chiapas through Central Amer- 
ica to Colombia. 
The Kentucky warbler, with its rich colors 
and symmetrical form, is to be classed among 
the elect of the warbler tribe. Moreover, while 
locally common it is never so abundant that it 
does not excite a thrill of interest in the breast 
of even the most blasé of bird observers. It 
loves the deep, dark forest and shaded ravine, 
where the foliage overhead casts heavy shad- 
ows on the plentiful undergrowth beneath and 
where even in midsummer it is moist and cool. 
The bird is a persistent singer, and in its 
own chosen haunts its loud, sweet song may be 
heard all day long. There is a curious resem- 
blance between its ditty and that of the Caro- 
lina wren, and while no one can mistake the 
two songs when heard close by, at a distance 
even the expert may be puzzled. This warbler 
finds most of its food on the ground, and the 
thick undergrowth in which it hunts makes it 
difficult to learn much of its habits by observa- 
tion, since it is difficult to keep an individual 
in sight many minutes at a time. 
It builds a rather loose, bulky nest, largely 
of leaves and grasses, which is placed either 
on or just above the ground, and although it 
may seem to have been rather artlessly located 
it is in reality well protected by the surround- 
ing vegetation with which it blends, and hence 
generally escapes the observation of all but the 
most persistent and sharp-sighted of observers. 
90 
WILSON WARBLER (Wilsonia pusilla 
pusilla) 
(For illustration, see page 96) 
Range: Breeds in Boreal Zones from tree 
limit in northwestern and central Mackenzie, 
central Keewatin, central Ungava, and New- 
foundland south to southern Saskatchewan, 
northern Minnesota, central Ontario, New 
Hampshire, Maine, and Nova Scotia; winters 
in eastern Central America ffom Guatemala to 
Costa Rica. 
This tiny warbler ventures farther north than 
many bigger and apparently hardier species, 
and Nelson found it in Alaska “one of the 
commonest of the bush-frequenting species, 
extending its breeding range to the 
shores of the Arctic Ocean wherever it finds 
shelter.” Cooke also found it in Colorado 
breeding from 6,000 to 12,000 feet elevation. 
The black-cap is a nervous, energetic, little 
fellow, now essaying the role of flycatcher, now 
hunting for insects among the foliage, while 
ever and anon it jerks its tail up and down as 
though constant motion were the chief end of 
existence. It has a short, bubbling, warbling 
song which has been likened to the songs of 
several other species, but which possesses a 
tone and quality all the bird’s own. Its nest is 
built on the ground, is composed chiefly of 
grasses, and the eggs do not differ in essential 
respects from those ,of other warblers. 
It is noteworthy that the West Coast form 
of the black-cap chryseola breeds as far south 
as Los Angeles, and that its nest instead of 
being built on the ground is placed in the 
crotch of a limb or in a bunch of weeds or 
nettles. 
CANADA WARBLER (Wilsonia 
canadensis) 
(For illustration, see page 96) 
Range: Breeds in the Canadian’ Zone and 
casually in the Transition from central Alberta, 
southern Keewatin, northern Ontario, northern 
Quebec, and Newfoundland south to central 
Minnesota, central Michigan, southern Ontario, 
central New York, and Massachusetts, and 
along the Alleghenies to North Carolina and 
Tennessee; winters in Ecuador and Peru. 
The Canada warbler is always associated in 
my mind with the black-cap, in company with 
which it is frequently found during migration. 
The association is purely accidental and results 
from a common preference for the same hunt- 
ing grounds. A path or road through swampy 
ground, especially if bordered by old willow 
trees, is sure to have its quota of this warbler 
and the Wilson black-cap during migration. 
Like the black-cap, the Canada warbler is 
half flycatcher, half warbler, and the click of 
the bird’s mandibles as they close on some 
hapless insect caught in mid-air is often the 
first indication of its presence. Unlike many 
of the family, it sings much during its spring 
migration. The song is loud for the size of 
the warbler and is very characteristic. The 
bird builds a rather bulky nest of leaves and 
grasses, which it places in a mossy bank or 
under a moss-grown log. It is an assiduous 
and active insect hunter and gleans among the 
leaves and twigs after the fashion of the 
parula warbler. 
