British Columbia--Atlin, August 26; Chilliwack, September 9.
Washington--Destruction Island, September 23. Oregon--Newport, September
18. California--Berkeley, October 10. Alberta--Edmonton, September 1.
Montana--Great Falls, September 25. Wyoming--Yellowstone National Park,
September 21. Colorado--Fort Morgan, October 2. Arizona--Organ Pipe
Cactus National Monument, October 17. Saskatchewan--East End, September
5. Manitoba--Oak Lake, September 18. North Dakota--Fargo, September 19.
South Dakota--Aberdeen, September 20. Kansas--Hays, September 23.
Texas--Somerset, October 8. Minnesota--Lanesboro, September 10.
Wisconsin--Milwaukee, September 20. Iowa--Marshalltown, September 26.
Missouri--Bolivar, October 26. Michigan--Grand Rapids, October 8.
Ontario--Ottawa, September 29. Ohio--Cleveland, September 30.
Illinois--Chicago, September 29. Kentucky--Hickman, September 23.
Mississippi--Gulfport, October 20. Louisiana--New Orleans, October 27.
Newfoundland--Tompkins, September 9. Quebec--Montreal, September 3. New
Brunswick--St. John, September 2. Nova Scotia--Yarmouth, September 11.
Maine--Winthrop, September 23. Vermont--St. Johnsbury, September 21.
Massachusetts--Stockbridge, October 1. New York--Rochester, October 30.
Pennsylvania--Berwyn, October 7. District of Columbia--Washington,
October 12. Virginia--Lexington, October 10. South Carolina--Charleston,
October 10. Georgia--Milledgeville, October 27. Florida--Fort Myers,
October 25.
Early dates of fall arrival are: Louisiana--New Orleans, July 15.
Mississippi--Bay St. Louis, July 7. Florida--St. Marks, July 18.
Mexico--Sonora, Sáric, July 31; Oaxaca, Tapanatepec, August 20.
Honduras--Lancetilla, August 27. El Salvador--Le Unión, August 1.
Nicaragua--Bluefields, August 22. Costa Rica--Puerto Limón, August 17.
Panamá--Almirante, August 13. Colombia--Bonda, Santa Marta Region,
August 27. Venezuela--Cantaura Anzoatique, September 27. British
Guiana--Abary River, September 2. Surinam--Paramaribo, August 28.
_Banding._--The majority of the banding recoveries indicate the return
to the place of banding and give records of longevity. Three birds
banded as adults at Wilton, N. Dak., were retrapped at the same station
in the following year. One banded at Sioux City, Iowa, on May 17, 1929,
was killed by an auto at the same place June 18, 1932. One banded at
Sault Ste. Marie, Mich., on May 30, 1926, was retrapped on May 29, 1929;
another banded at the same station, May 20, 1928, was killed by an auto
June 28, 1934. A yellow warbler banded at North Eastham, Cape Cod,
Mass., on May 28, 1931, was retrapped at the same station May 15, 1932,
May 18, 1936, and August 6, 1937.
_Casual records._--The yellow warbler has twice been collected in
Bermuda: November 23, 1875; and October 14, 1903. It has also been
observed near Habana, Cuba, on September 3 and 10, 1939. There are three
winter records in South Carolina; it was seen at a feeding station at
Summerville in the winter of 1939 and on January 21, 1940; and at
Charleston on January 18, 1947.
_Egg dates._--California: 110 records, April 16 to July 15; 56 records,
May 21 to June 19, indicating the height of the season.
Massachusetts: 113 records, May 19 to June 30; 82 records, May 27 to
June 7.
Minnesota: 26 records, May 29 to June 23; 17 records, May 29 to June 8.
New Jersey: 32 records, May 15 to June 24; 24 records, May 26 to June 7.
Utah: 23 records, May 8 to July 16; 12 records, June 6 to 17.
Washington: 21 records, May 28 to June 24; 11 records, June 2 to 7.
Baja California: 11 records, May 8 to June 12; 6 records, May 15 to June
2, indicating the height of the season.
Mexico: 6 records, June 4 to 20 (Harris).
DENDROICA PETECHIA AMNICOLA Batchelder
NEWFOUNDLAND YELLOW WARBLER
HABITS
Based on a series of 14 adult males and 3 adult females from
Newfoundland, Charles F. Batchelder (1918) gave the above name to the
yellow warblers that breed in that region. After giving a detailed
description of the type from Curslet, Newfoundland, he remarks: "When
seen in series, the yellow of the under parts is duller, less richly
golden, and the chestnut streaks are darker. In comparison with
_aestiva_, the female is duskier, less yellowish, throughout the upper
parts. * * *
"In general coloring _D. ae. amnicola_ shows a certain similarity to _D.
ae. rubiginosa_, but it is readily distinguishable from that race by the
yellow forehead which, as in _D. ae. aestiva_, contrasts strongly with
the green of the back."
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."
As evidence of the late migration of this subspecies, Robie W. Tufts
writes to me from Nova Scotia: "The latest date of departure which
appears to be normal is October 7, 1936, though they generally leave
during the second week of September. On November 25, 1929, a female was
collected by me at Wolfville. The bird was searching for food very
actively and its general behavior was decidedly abnormal. The bird's
body showed slight traces of emaciation." Birds that have been recorded
in Massachusetts as late as September 30, long after our local breeding
birds have left, were probably of this subspecies.
DENDROICA PETECHIA RUBIGINOSA (Pallas)
ALASKA YELLOW WARBLER
HABITS
This subspecies was formerly supposed to range throughout most of
Alaska, but its breeding range is now understood to be restricted to the
coast region of southern Alaska and British Columbia, from Kodiak Island
(the type locality) southward to Vancouver Island. It migrates through
California to Mexico and Central America, and probably spends the winter
in South America. In El Salvador, according to Dickey and van Rossem
(1938), "this race was found only as a fairly common spring migrant
through the upper levels of the Arid Lower Tropical. As with _D. p.
aestiva_ the winter range undoubtedly lies farther to the south. It is
notable that _rubiginosa_ occurs at somewhat higher elevation than the
other three forms and was not found at all in the 'tierra caliente.'"
This race has been reported in Kansas and in central Texas, but these
birds may have been _amnicola_, which somewhat resembles _rubiginosa_
and which had not been accepted at that time.
Ridgway (1902) describes the Alaska yellow warbler as "similar to _D.
ae. aestiva_, but slightly smaller and much duller in color. Adult male
darker and duller olive-green above, the pileum concolor with the back
or else becoming slightly more yellowish on forehead (very rarely
distinctly yellowish on forehead and fore part of crown); wing-edgings
less conspicuous, mostly yellowish olive-green, sometimes inclining to
yellow on greater coverts. Adult female darker and duller olive-greenish
above, duller yellow below." He might have added that the chestnut
streaks on the breast are narrower than in _aestiva_.
Nothing seems to have been published on the nest and eggs of the Alaska
yellow warbler, nor on its habits, all of which probably do not differ
materially from those of the species elsewhere in similar environment.
DENDROICA PETECHIA MORCOMI (Coale)
ROCKY MOUNTAIN YELLOW WARBLER
HABITS
This is another race that was described many years ago by H. K. Coale
(1887) but has only recently been accepted by the A. O. U. Coale gave it
its scientific name in honor of J. Frean Morcom and called it the
western yellow warbler. The following remarks by Dickey and van Rossem
(1938) tell the story very well:
The race of yellow warbler summering in the Great Basin and Rocky
Mountain regions of the United States of late years has been generally
overlooked and has been synonymized commonly with _aestiva_ or, in part,
with _brewsteri_. Although not a well differentiated form, its
characters are readily apparent in series, and there is no reason why it
should not be accorded equal standing with the races currently
recognized. The underparts of the males are heavily marked, and in this
respect _morcomi_ is not distinguishable from _aestiva_. Dorsally,
however, _morcomi_ is darker and less yellowish green, particularly on
the interscapular region. The females are, age for age, more buffy (less
yellowish) below and darker and more grayish above than the females of
_aestiva_. In comparison with _brewsteri_, _morcomi_ (particularly the
bill) is larger, and the males are more heavily streaked below. The
range of _morcomi_ is the Rocky Mountain region of the United States,
north to Wyoming and Idaho, west to the eastern slope of the Sierra
Nevada, and south (in the western part of its range) to Mammoth, Mono
County, California. We have not seen material from the southern Rocky
Mountains; so we cannot state the southern limits in that region.
They call it a "common spring and fall migrant and winter visitant in
the lowlands," of El Salvador. "Dates of arrival and departure are
August 1 and April 9."
Angus M. Woodbury has sent me a copy of the manuscript for "The Birds of
Utah," by Woodbury, Cottam, and Sugden, from which I infer that the
haunts, nesting, and other habits of the "western yellow warbler," as
they call it, do not differ materially from those of the well-known
eastern bird. They say of its status in Utah: "This yellow warbler is a
common summer resident from early May to late August, the vanguard
sometimes reaching here in late April and stragglers sometimes lingering
into September, the latest record being September 23. It is primarily a
bird of the riparian growths along water edges, either of streams, ponds
or lakes or irrigated areas, particularly of the valleys and lower
canyons, but occurs higher in the canyons in suitable habitat up to at
least 8,000 or 9,000 feet. It does not seem to be attracted to large
trees such as cottonwoods, but seems to prefer the more leafy shrubbery
and small trees of developmental stages in ecological succession. In
migration, it sometimes leaves this niche and may occasionally be found
elsewhere. * * *
"In nesting, it is usually found in a bush, chaparral or small tree
stratum, seldom going to the ground or to the tops of trees. Its nests
are compactly woven cups generally placed from 3 to 10 feet above
ground, sometimes 15 feet, in rosebushes, willows, choke cherries,
hawk-berries, oaks, young cottonwood or boxelder trees, usually within a
short distance of the water's edge. The nest is usually composed of gray
plant fibers, bark shreds or grasses and is usually lined with some
downy substance such as cottonwood or willow cotton or hair."
DENDROICA PETECHIA BREWSTERI Grinnell
CALIFORNIA YELLOW WARBLER
HABITS
The 1931 A. O. U. Check-List gives the breeding range of this subspecies
as the "Pacific coast strip from western Washington south through Oregon
and California, west of the Great Basin and southeastern deserts to
about lat. 30° in Lower California." It intergrades with _rubiginosa_ on
the north and with _morcomi_ to the eastward, but exact boundaries are
difficult to define. It seems to range well up into the mountains, for
James B. Dixon tells me that he has found it nesting in Mono County,
Calif., at altitudes of 6,500 to 9,200 feet.
Dr. Joseph Grinnell (1903) in an interesting study of western yellow
warblers, bestowed the above name on the California bird, for which he
gives the following subspecific characters: "Resembling _Dendroica
aestiva aestiva_, from which it differs in smaller size, paler (or less
brightly yellow) coloration, and, in the male, narrower streaking on
under surface; differs from _Dendroica aestiva rubiginosa_ in much
smaller size and yellower coloration, and from _Dendroica aestiva
sonorana_ in smaller size and much darker coloration."
_Spring._--Both _rubiginosa_ and _brewsteri_ occur in California and in
Washington on migrations. As it is difficult to distinguish the two
forms in life, some of the following remarks may refer to either or both
of these two subspecies. Mrs. Amelia S. Allen writes to me that this
species "is the latest of the warblers to arrive in the San Francisco
Bay region for the breeding season. Sometimes they are here by April 8,
but the average date is about April 18. At Lake Tahoe, the first week of
June, breeding pairs were settled in the willows and migrants on their
way farther north were migrating through."
Samuel F. Rathbun says in his Washington notes: "Our experience with
this species, based on many years of observation, is that the birds in
the spring migration progress northward in a series of what may be
called waves. Invariably the first noted will be one or two individuals,
and these are heard for a short time only and evidently move on. Then
there is a break of a day or so before the next are heard, a larger
number. A period of a day, or perhaps two or three, may again elapse
before the main body of birds arrive and they are heard on all sides.
Common in and about the city at this period, it haunts the shade trees
lining the streets and the fruit trees in the gardens, but is not at all
partial to the outlying sections, except in the more cultivated areas
and the orchards. It is essentially a bird of the older settled
districts, wherever fruit trees and deciduous trees may abound."
For May 6, 1924, he remarks, "These warblers drifted by all day, in ones
and twos or threes, straggling, but, although seemingly widely
separated, always within hearing distance of each other. At times there
will be a break when apparently none are passing, then in the distance
the song will be heard again, soon growing louder, as the bird draws
nearer, following in the wake of others that have preceded him, his song
in turn growing fainter in the distance after he has passed."
_Nesting._--The summer haunts and nesting habits of the California
yellow warbler are generally similar to those of the eastern bird.
Grinnell and Storer (1924) write:
Yellow warblers nest abundantly on the floor of Yosemite Valley. Some of
the nests are in growths close to water, whereas others are located in
brush tangles or other rank growths back some distance from the streams.
A nest found June 7, 1915, may be taken as fairly typical. It was 52
inches above the ground in the crotch of a forking stem of a chokecherry
which grew in a clump of the same plant, and was shaded by a black oak.
As usual it was higher than wide outside, being 3-1/2 inches in height
by 3 to 3-1/4 inches in diameter. The cuplike cavity was 1-3/4 inches
across at the top and the same in depth at the center. Shreds of bark
and flat plant fibers were the principal materials used in construction,
the lining being of horsehair and a few feathers.
One nest was "4 feet above the ground in a mountain lilac (_Ceanothus
integerrimus_)," and another "was placed about 15 feet above the ground
in a small pine tree growing at the margin of a pond. It rested on the
next to the topmost whorl of branches and one side was against the
slender trunk of the tree."
In the Lassen Peak region, Grinnell, Dixon, and Linsdale (1930) report
four nests in willows, one in a wax-berry (_Symphoricarpos_), one in a
snowbush, and one fastened between stems of rose and willow at the edge
of a clump of rose.
_Eggs._--Three or four eggs seem to constitute the commonest set for the
California yellow warbler. These are hardly distinguishable from those
of the eastern bird, though they average, perhaps, more heavily marked.
The measurements of 40 eggs average 16.6 by 12.4 millimeters; the eggs
showing the four extremes measure =18.3= by 13.5, 17.8 by =15.0=, =14.7=
by 12.2, and 16.3 by =11.4= (Harris).
_Food._--Prof. F. E. L. Beal (1907) analyzed the contents of 98 stomachs
of California yellow warblers, and found that the animal matter amounts
to 97 percent of the food, consisting wholly of insects and a few
spiders.
The largest item is Hymenoptera, which amounts to over 30 percent,
almost half of which are ants. The remainder are small bees and wasps,
some of which are probably parasitic species, though none were
positively identified. * * * Caterpillars, with a few moths, aggregate
over 18 percent.
Beetles form nearly 16 percent of the diet, and embrace about a dozen
families, of which the only useful one is that of the ladybirds
(_Coccinellidae_), which are eaten to a small extent. The great bulk of
the beetle food consists of small leaf-beetles (_Chrysomelidae_), with
some weevils and several others. One stomach contained the remains of 52
specimens of _Notoxus alamedae_, a small beetle living on trees. Bugs
(Hemiptera) constitute over 19 percent of the food, and are eaten
regularly every month. Most of them consist of leaf-hoppers (Jassidae)
and other active forms, but the black olive scale appeared in a number
of stomachs. Plant-lice were not positively identified, but some
stomachs contained a pasty mass, which was probably made up of these
insects in an advanced stage of digestion.
Flies seem to be acceptable to the summer warbler; they are eaten to the
extent of nearly 9 percent. Some of them are of the family of the house
fly, others are long-legged tipulids, but the greater number were the
smaller species commonly known as gnats. A few small soft-bodied
Orthoptera (tree-crickets), a dragon-fly, and a few remains not
identified, in all about 5 percent, made up the rest of the animal food.
Only about 2-1/2 percent of the food was vegetable matter, made up
mainly of fruit pulp in a single stomach, one or two seeds and rubbish.
Rathbun (MS.) says that this warbler "shows some partiality for feeding
on aphids, for we have many times watched it in an orchard carefully
scanning the leaves on a tree for this insect."
All other phases of the life histories of this and the following two
subspecies do not seem to differ materially from those of the eastern
yellow warbler and need not be repeated here.
_Fall._--According to Rathbun's notes, all the resident, breeding yellow
warblers have departed from Washington "by the latter part of August,
and in some seasons we have not heard the bird after the twenty-fifth;
it is one of the few species that sing more or less during all of its
sojourn here, and its song in late summer is almost as good as on its
arrival in the spring. A break in the movement south of this species
seems to occur about August 20 to 25. Then, early in September, the
notes of the yellow warbler begin to be heard again. We have the idea
that these may be of the Alaska yellow warbler."
Mrs. Allen writes to me from Berkeley, Calif.: "Breeding birds leave the
bay region in late July or early August; migrants from farther north
begin to go through in September; the latest date on which I have seen
them is October 16, 1920. I usually see them in the shade trees along
the streets or in the woods when they come to bathe in my bird pool. But
I have two records which show them in very different situations:
September 18, 1933, on a hill slope that had been recently burnt over, a
group of these warblers with horned larks and Savannah sparrows; and on
September 25, 1941, at Point Reyes lighthouse, hunting for food in the
low, dry lupines just inside the rocky point. One could not help
wondering if they had just come to a landing place after a long flight
over the ocean. They were in immature plumage."
According to the 1931 Check-List, the California yellow warbler
"migrates through eastern California, Arizona, and Lower California;
winters sparsely in the Cape District of Lower California and south to
Guatemala, Nicaragua, and Costa Rica."
_Winter._--Dickey and van Rossem (1938) record this warbler as a "winter
visitant and spring migrant in the Arid Lower Tropical Zone," in El
Salvador. "The small Pacific coast race, _brewsterii_, is apparently
relatively the least common of the four forms found in El Salvador; at
any rate, the small number of specimens taken indicates that this is the
case. Yellow warblers were common in January at Puerto del Triunfo and
in February at Rio San Miguel, but unfortunately only one specimen was
taken at each place. Whether all of these winter birds were _brewsteri_
and _morcomi_ is problematical."
DENDROICA PETECHIA SONORANA Brewster
SONORA YELLOW WARBLER
HABITS
This is the palest of all the yellow warblers, one of the many pale
races of the southwestern desert regions. Its breeding range extends
from southeastern California, southern Utah, Arizona, and New Mexico to
central western Texas, Sonora, and Chihuahua; and it winters from Mexico
southward to Guatemala, Nicaragua, and Costa Rica.
It is best described by Ridgway (1902) as "similar to _D. æ. æstiva_,
but much paler; adult male lighter and much more yellowish olive-green
above, the back frequently (usually?) streaked with chestnut, pileum
usually wholly clear yellow, lower rump and upper tail-coverts yellow,
faintly streaked with olive-greenish; wing edgings all yellow; under
parts lighter yellow than in _D. æ. æstiva_, and with chest and sides
much more narrowly (often faintly) streaked with chestnut; adult female
conspicuously paler than in _D. æ. aestiva_, the upper parts often
largely pale grayish, the under parts usually very pale buffy yellow."
Woodbury, Cottam, and Sugden (MS.) say of its status in southern Utah:
"This race of yellow warbler is a breeder of the streamside fringes of
willows, tamarix, and brush of various kinds along the San Juan and
lower Colorado Rivers. It undoubtedly extends up the Colorado above the
mouth of the San Juan, but how far it extends before yielding to
_morcomi_ has not been determined. Data available are not sufficient to
determine its nesting or migration dates or the length of its stay in
Utah."
Swarth (1914) calls it "a common summer visitant in southern and western
Arizona, apparently confined almost entirely to the Lower Sonoran river
valleys, the Colorado and the Gila, with their tributaries. * * * I know
of no breeding record of a yellow warbler from any point in Arizona
north of the Mogollon Divide." Mrs. Bailey (1928) says that "the lower
Rio Grande in New Mexico apparently marks the most northern extension of
the range of the Sonora Yellow Warbler. It is a common breeder at
Mesilla," which is in the southwestern part of the State.