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A
chapter from the electronic book:
Life Histories of Familiar North American
Birds
Evening
Grosbeak
Coccothraustes vespertinus
[Eastern Evening Grosbeak]
Contributed by Doris Huestis Speirs
[Published in 1968:
Smithsonian Institution United States National Museum Bulletin 237
(Part 1): 206-237]
The evening grosbeak was first described by William Cooper
(1925) from a specimen sent to him by Henry R. Schoolcraft from
Sault Ste. Marie, Mich. The first words written about it were
those Schoolcraft (1851) penned in his journal for Apr. 7, 1823:
"During severe winters in the north, some species of birds
extend their migrations farther south than usual. This appears to
have been the case during the past season. A small bird, yellowish
and cinereous, of the grosbec species, appeared this day in the
neighbourhood of one of the sugar-camps on the river below, and
was shot with an arrow by an Indian boy, who brought it to me. The
Chippewas call it Pashcundamo, in allusion to the stoutness
of its bill, and consequent capacity for breaking surfaces."
William Cooper (1825), in his observation following the
original description, quotes from the notes of Major Delafield
who, as agent of the United States for boundaries, met the bird in
August 1823 near the Savannah River, northwest of Lake Superior:
At twilight, the bird which I had before heard to cry in a
singular strain, and only at this hour, made its appearance close
by my tent, and a flock of about half a dozen perched in the
bushes in my encampment. They approached so near, and were so
fearless, that my canoe-men attempted to catch them, but in vain.
I recognized this bird as similar to one in possession of Mr.
Schoolcraft, at the Sault Ste. Marie.
Its mournful cry about the hour of my encamping (which was
at sunset) had before attracted my attention, but I could never
get sight of the bird but on this occasion. There is an extensive
plain and swamp through which flows the Savannah river, covered
with a thick growth of sapin trees. My inference was then, and is
now, that this bird dwells in such dark retreats, and leaves them
at the approach of night.
Major Delafield's inference is the source of the species'
vernacular name--manifestly a misnomer. I do not doubt that the
good major's birds cried out at sunset "in a singular
strain" because he and his party disturbed them as they made
camp. Ordinarily the species is not crepuscular, and in fact it
might better be called "morning grosbeak," for it is
most active early in the day. *** And it inspired Elliott Coues
(1879) to write: "A bird of the most distinguished
appearance, indeed, is the Evening Grosbeak ***. Clothed in the
most striking color-contrasts of black, white, and gold, he seems
to represent the allegory of diurnal transmutations; for his sable
pinions close around the brightness of his vesture, just as the
night encompasses the golden hues of the sunset; while the clear
white space enfolded in these tints foretells the dawn of the
morrow."
Before 1854, in addition to the localities mentioned in
Cooper's account, this grosbeak had been reported from Lake
Athabaska (Bonaparte, 1828), from Carlton House and the
Saskatchewan plains, where it was known as the
"sugar-bird" (W. Swainson and J. Richardson, 1831).
Forbush (1929) tells of the eastward extension of range:
The first recorded extension of its range east of the Great
Lakes was at Toronto in 1854. About the beginning of the last
quarter of the nineteenth century there seems to have been some
increase of the species in winter in the northern tier of
mid-western states. The first verified occurrence of the species
in Indiana, according to Dr. A. W. Butler, was in November, 1878,
although it was reported there in 1876. In the winter of 1886-87
its numbers increased in Indiana, and it was noted in Ontario and
also in some numbers in western Kentucky in the spring of 1887,
and a few reached New York state. Up to the winter of 1889-90,
however, it was almost unknown in the East, and even as far west
as Ohio. In that winter a great eastward migration occurred, which
in January, 1890, penetrated almost to the Atlantic coast of
Massachusetts.
By February 1890 the birds had reached Revere Beach, on the
Atlantic Coast of Massachusetts, and finally the migration reached
as far east as the city of Quebec, and east in Maine as far as
Orono.
Mr. Bent writes of his first youthful encounter with "this
fine, large, and handsome grosbeak" as follows: "It was
on March 8, 1890, that I saw my first evening grosbeak. I was
leaving my father's house to go to work in a cotton mill in Fall
River, when I saw three plump, handsome birds feeding on the buds
of a sugar maple in the front yard. I promptly forgot about the
mill job, and soon had two fine males and a female laid out on my
skinning table. This was, I believe, the first record for the
species in southeastern Massachusetts. Since then, at frequent
intervals, we have had them here at feeding stations, sometimes in
large numbers."
In his comprehensive study of the summer distribution of the
eastern evening grosbeak, James L. Baillie (1940) maps 82 summer
records. These form an almost continuous belt on both sides of the
international boundary, from southeastern Manitoba to eastern
Ontario, and concentrated mainly in the vicinity of the Great
Lakes. He also gives 6 summer records for Alberta, 1 for
Saskatchewan, 4 for Manitoba and 6 for New England. Many of these
birds seen or collected in June, July, or August at least suggest
the possibility of breeding. In several cases parents were seen
with recently fledged young apparently hatched in the vicinity.
Baillie's table gives full references for all the records, which
he summarizes as follows:
The more recent and regular occurrences of the species in
eastern North America in winter seem to be correlated with an
increase of the species in summer and it seems evident that its
summer range has been extended eastward by gradual stages during
comparatively recent years. . . . Facilitating their eastward
extension has been the widespread planting in the east during the
past few decades of the box elder (Acer negundo) as a shade
tree (Allen, 1919). The seeds of the box elder, which hang on the
trees all winter, are preferred by the evening grosbeak to
anything else, when available, and Taverner (1921) calls the
situation a "baited highway" along which the grosbeaks
have been able to pass.
In the 25 years since publication of Baillie's paper, the
grosbeaks have continued to extend their range eastward. They have
now been reported from Newfoundland in winter and from eastern
Quebec, New Brunswick, and Nova Scotia in summer. It is probably
only a question of time before their breeding in the easternmost
Maritime Provinces and Newfoundland is reported.
Spring.---"When the snow is
heavy the birds congregate at feeding stations," writes
Christopher M. Packard. "When it thaws, and the ground and
seeds begin to appear again, their attendance at feeders drops
noticeably, doubtless because the birds can now find enough
natural food. They can once again revert to the maple stands and
rummage about through the soggy leaves in search of seeds fallen
the autumn before. With the advent of warmer weather, two new
sources of food becomes available, the new tender buds and the
maple sap, of which they are particularly fond."
At North Bay, Ontario, the grosbeaks arrived early one winter
at the western edge of the town. Day by day they visited various
box elder or Manitoba maple trees (Acer negundo) and in a
kind of micro-migration moved eastward across the town until, by
the time the snows melted, they had reached its eastern limits. On
a March day in 1945 we watched a small flock feeding in a Manitoba
maple. The birds kept flying from the tree to a snow-covered house
roof nearby to eat snow. Individual birds went to a dark patch on
the roof where the snow was melting, filled their bills with the
water, threw back their heads and drank. My notes written at the
time read: "The wind was blowing and waving the innumerable
samaras to a tinkling music. The sound of the blowing seeds, of
the birds' musical chatter, was like an elfland symphony to our
ears." Wings and seeds lay scattered in the snow beneath
every Manitoba maple the grosbeaks had visited. We examined many
of the now seedless wings, bitten off with neatness and precision.
Later that spring in the Haliburton District of Ontario we
found the grosbeaks feeding beneath the mountain maples (Acer
spicatum). A flock was actively searching for the fallen seeds
amongst the forest litter. They were quiet when feeding, but
punctuated their activity with loud call notes as various members
of the flock flew up into yellow birch or spruce and down to a
little stream under alders to drink. They drank the cold pure
water of this northern stream with as much apparent relish as the
North Bay grosbeaks drank the melted snow from the city rooftops.
In Ontario, New York, and New England, small flocks move from
feeding station to feeding station on the way to the breeding
grounds. As evening grosbeaks are not early nesters, a few birds
often remain in the vicinity of feeding stations until May. In
recent years May reports have come from states south of New York
and New England. But gradually the flocks diminish in size until
the last bird has left.
Courtship.--After watching a
pair of evening grosbeaks on their breeding ground in northern
Michigan, Bayard H. Christy (1930) gave the first published
account of the colorful courtship display. He writes: "As the
female. . .perched near, the male made a beautiful display. He
crouched low, puffed out his plumage, extended his wings
horizontally and set them quivering. The gorgeous contrast of the
glossy black wings with the golden body suggested the appearance
of a bird of paradise. There was no song; it was about half past
five in the afternoon, and the sun was still high."
On Apr. 4, 1937, at Hanover, N.H., I watched a pair of evening
grosbeaks bowing to each other with great formality. They were not
more than a foot away from each other when the formalities began.
First the male bowed very low, then the female bowed. The male
bowed again, and the female again. The rhythm accelerated until
they were bowing so low that I almost expected to see them lose
their balance and fall off the branch. The female punctuated her
jerky movements with loud call notes. As she bowed she called peter!
and flicked her tail. From the male came no sound. The female
seemed the more enthusiastic, and continued to bow after the male
apparently had lost interest. On April 21 I saw a female jerking
up and down in somewhat the same way a flicker does during
courtship. She seemed to be pursuing the male, or at least she
moved toward him, but he disregarded her, dropped to a lower
branch, and turned his back to her.
While observing two pairs at a salt lick by Clear Lake,
Haliburton County, Ontario, on June 1, 1945, I noted that the
females were as combative as the males, spreading their wings,
jerking from side to side, and clinching bills. During one duel
the two females rose into the air as fighting male robins
sometimes do.
On May 2, 1949, in Iron County, Mich., among a loosely
scattered flock in the crown foliage of tall sugar maples at noon
I watched (Speirs, 1949) a male in courtship display: "The
pair were about 40 feet up in a maple, the male about a foot above
the female on another branch. Suddenly he threw back his head,
lowered the yellow rump, raised and fanned his black tail and
commenced vibrating his black and white wings so fast that they
looked transparent as a hummingbird's. He then glided along the
branch above her as swiftly as a geisha, but with his back in the
form of a U. The female did not look at all impressed, flew to a
tree eastward, followed by her swain."
Elizabeth Holt Downs (1958) has given a full account of the
courtship as she observed it on Glebe Mountain, South Londonderry,
Vt., in the spring of 1956. She writes:
During the first part of April the grosbeaks began
"chasing" each other and on April 18th I witnessed the
first courtship feeding. . .the female initiated this first
feeding by "flirting" her tail (a quick spreading and
closing of the tail), bobbing her head and swinging her body
slightly in front of the male. Some males do not respond at first
to this invitation but in this instance the male fed the female
sugar maple buds. Within a few days courtship feeding was a daily
occurrence. On one occasion I watched a male grosbeak go through
all the motions of feeding a female but without any food to give
her. . . .
Beginning with 1953 I have been able to observe much of the
courtship behavior of the Evening Grosbeaks every year. Their
courtship seems to follow a certain pattern with possibly some
slight variations. It is initiated by the female asking to be fed.
The first food she receives from the male is tree buds; later she
is fed salt-impregnated earth and still later (after pair
formation has taken place) the female is fed sunflower and tree
seeds. After pair formation has occurred, more often than not it
is the male who takes the initiative and offers the seeds to the
female. At this time when the female accepts the food (or asks for
it) she assumes a posture similar to that of the young begging to
be fed (crest raised, body crouched slightly and wings
fluttering). Some females swing their bodies from side to side and
occasionally a female will "cry." But sometimes the
feeding is accompanied by very little display by the female.
"Dancing" by the males usually begins shortly
after the initial courtship feeding and before pair formation has
taken place. When dancing, the male grosbeak faces the female.
With crest raised, bill and tail pointed upwards, breast almost
touching the ground and wings drooped but spread wide and
vibrating, he slowly pivots back and forth. He does not sing while
dancing. If he utters any sound at all, it is too low for me to
hear.
On June 1 she witnessed two matings. The second "was a
very elaborate ceremony. . . . The pair, on the road in front of
our house, faced each other. The male danced (but all his
movements were more subdued than in the usual dance). The female
quivered her wings (short, rapid movements with wings held close
to her body) and held her tail high. Then still in this posture
but with her breast thrust forward she hopped a few inches to the
dancing male. I could not be certain that their breasts touched.
She continued to dance. It looked as if they touched bills twice.
He then mounted her."
Nesting.--For 75 years after the
discovery of the eastern evening grosbeak, its breeding range
remained virtually unknown. Of its nesting habits nothing was
reported until L. Osborne Scott sent some notes to W. T. Macoun
(1899) in which he announced: "I have seen the Evening
Grosbeaks in flocks of ten to eighty on the Peace River. The
Indians say they always build in Saskatoon willows (Amelanchier),
though I think there are exceptions."
Macoun also published Scott's account of nests he found near
Winnipeg that year. "On the 18th of June I saw four nests of
the Evening Grosbeak about one mile north of Winnipeg, near the
Red River, in fact right on its bank. The nests were about twelve
or fifteen feet from the ground in some grey willows; they were
rather flat and slight, made of sticks and roots and lined with
smaller roots. There were only two eggs in two nests and one each
in the other two. The eggs were more blotched than those of the
Red-breasted and not so spotted, and I fancy they are a little
smaller."
Ten years later came a report from Sidney S. S. Stansell (1909)
that he had located a nest 30 miles northwest of Edmonton, Alberta
in June 1908 "which contained a dead full-fledged young male.
The nest was 40 feet up in a white birch tree."
Dr. S. C. Kendeigh, who found a pair building in a white birch
in the Thunder Bay District of Ontario in 1945, writes: "I
found the evening grosbeak quite common in Algonquin Park and only
a little less so north of Port Arthur. On June 22 I found a pair
nest-building on one of my plots. Only the base of the nest was in
position in a vertical crotch 55 feet up in a white birch that was
60 feet tall. I watched them only five minutes to avoid disturbing
them, but in this time the female made 5 visits to the nest with
dead twigs. These twigs she broke off a smaller white spruce about
two-thirds of the way up. She broke them off with her bill, once
dropping two before taking the third to the nest. At the nest she
jumped into the center and adjusted the stick into the structure
on the outside. It was a hot day, in the high 80s, and the female
was panting with mouth wide open and wings partly spread. The male
accompanied the female on each trip to and from the nest but did
not help in the building. He would watch her intently at the nest
while perched on a branch a few feet below."
J. Stokley Ligon (1923) found five nests of the eastern evening
grosbeak on July 28, 1923, on Whitefish Point, Lake Superior, in
Michigan, about 20 miles from the Canadian shore. One young bird
was found on the ground, and the nest from which "it had
fallen was about 25 feet up on a horizontal limb of a white pine,
well concealed by small branches and needles." He climbed to
this nest and examined it, which "was practically
indistinguishable from nests of the Black-headed Grosbeak of the
West, being almost, if not quite, as frail of construction. . . .
The body of the nest was composed of hard, clean sticks and lined
with black and brown hair-like rootlets, with a sprinkling of moss
between the outer body and lining."
Thomas S. Roberts (1932) quotes an account published by A. G.
Lawrence in the Winnipeg Free Press, June 20, 1930, of two nests
near Winnipeg found by L. E. McCall, of Selkirk, Manitoba. One
nest was "placed in a crotch 28 feet up in a Manitoba maple
situated in a garden bordering the public sidewalk, and. . .well
concealed except on one side." The other nest was 19 feet up
in an elm overhanging the road, "on a fork of a long
overhanging branch." Both nests contained eggs and the two
birds sat closely. During the first three decades of the present
century, while the eastern evening grosbeak was extending its
summer range eastward, many records of probable nesting were based
on females showing brood patches and on adults seen feeding
juveniles. At Woodstock, Vt., Richard M. Marble (1926) saw four
young come to a feeding station with their parents. "The
little ones were not quite as large as the adults, their tails
were very short and many downy feathers still showed on their
heads."
H. R. Ivor sent Mr. Bent an interesting account of some evening
grosbeaks he had in his aviary for several years. He told
especially of one pair that mated, built a nest, laid four eggs,
and succeeded in raising one young. J. H. Fleming (1903) also
records the breeding of this species in captivity.
Louise de Kiriline Lawrence, my husband, and I found a nest
near a forest edge in Lauder Township, Nipissing District,
Ontario, on June 21, 1945 (Speirs and Speirs, 1947). The nest was
55 feet up in a white pine and very well concealed. It contained
at least three young and through a 47X telescope we were able to
watch the young being fed. I spent 3 days observing this nesting.
After the young left we collected the nest, which is now in the
Royal Ontario Museum of Zoology and Palaeontology. Its
measurements are: Inside of cup--longest diameter, 3.7 in.;
shortest diameter, 3.2 in; Outer diameters--longest, 5.9 in.;
shortest, 4.3 in.; Depth of cup--2.8 in.; Total depth--5.1 in. to
supporting limb; 5.9 ins. including twigs below limb. Most of the
foundation of the nest is of twigs from deciduous trees (maple,
birch, viburnum, red-osier, dogwood), a piece of vine (possibly
bittersweet), twig of raspberry. Many of the twigs are opposite
branching (maple, viburnum, dogwood). The smaller twigs are from
coniferous trees, mostly from spruce, some from balsam fir, and
one from tamarack. The edge of the nest is of rootlets interwoven
with Usnea lichen. The innermost lining is of what appears
to be black moss--the dead stage of threadlike lichens. Dr. C. H.
D. Clarke assisted with the identification of the nest material.
The following summer (1946) grosbeaks were found nesting some
10 miles south of Lauder Township in Algonquin Park. Says C. E.
Hope (1947):
During the last week of May, a road, about one and one-half
miles in length, was bulldozed through a mixed forest of
second-growth white pine, black and white spruce, balsam and
birch. The action of the scraper exposed a myriad of rootlets
which, after a few days, became dry and brittle. Coinciding with
this period at least ten pairs of Evening Grosbeaks established
themselves in what might be termed a loose colony, in woods
adjacent to a section of this road. Pairs were frequently seen on
the freshly graded earth. On June 10, a female, accompanied by her
mate, was observed to carry off rootlets in her bill. On June 12,
a similar observation was made and on this occasion we were
fortunate enough to see where the material was taken and
deposited. The performance was repeated several times, with only
the female carrying the material but always accompanied by the
male. The nest, situated 28 feet from the ground in a black
spruce, was left undisturbed until June 22 when it was collected.
It was found to be placed close to the trunk some six or seven
feet from the top of the tree and almost entirely hidden by dense
foliage. It contained four slightly incubated eggs.
On June 21 a second nest was discovered 30 feet 5 inches up
in a balsam. Like the first, it was invisible from the ground and
was situated close to the trunk, six or seven feet from the top.
It contained three eggs on the date mentioned. This nest was left
undisturbed until July 6. It was then found to contain three
partially fledged young. One, taken for a specimen, proved to be a
male. . .The remaining two young left the nest on July 8. . . .
A point of interest concerning the structure of the two
nests found is that from seventy-five to ninety percent of the
materials used consisted of rootlets such as were exposed in the
newly made road. Oddly enough, the taking up of nesting
territories adjacent to the road coincided with the exposure of
unlimited nesting material.
Marjory B. Sanger reported in a letter to me the first nesting
I have heard of for the Province of Quebec. Between May 26 and May
30, 1955, she watched a pair of evening grosbeaks gathering
nesting material and carrying it into a 60-foot white birch that
stood in a fairly open spruce and maple glade near St. Charles de
Mandeville, Conte Berthier. The nest was about 30 feet up and the
female seemed to be doing all the nest-building. The male,
however, "observed her actions with obvious interest. . .
supervising with care and staying close at all times."
Evening grosbeak nests have three outstanding characteristics:
they are loosely constructed "stick-nests"; some moss or
lichen is woven into the structure; and the cup is not really
round (as has been reported) but oblong or elliptical. They have
been reported in seven species of coniferous trees: balsam-fir,
red spruce, black spruce, white pine, Norway (or red) pine, jack
pine, and white cedar. The species has also nested in at least
seven species of deciduous trees: willow, aspen, white (or paper)
birch, elm, Saskatoon (Amelanchier), and in hard and soft
maples. One nesting was in an orchard.
Eggs.--The evening grosbeak lays from
two to five eggs in a set, usually three or four. The eggs are
ovate or, rarely, pointed ovate, thin shelled, and of smooth
texture with little gloss. The ground color is usually deposited
as a clear blue or bright blue-green, which during incubation
changes to "pale blue-green" or "pale glaucous-green."
They are blotched and spotted, particularly at the larger end,
with "olive-brown," "lilac gray," or
"light Quaker drab." Fine pencilled markings in black
occur on a number of eggs. One with a "pale glaucous-green"
shell was stippled all over with "olive-gray" and
"pale mouse gray." The eggs resemble rather strikingly
those of the red-winged blackbird.
The measurements of 23 eggs average 24.5 by 17.5; those showing
the four extremes measure 28.0 by 18.0, 26.8 by 19.0,
21.0 by 16.0, and 21.0 by 16.0 millimeters.
Incubation.--One egg is laid
each morning until the set (usually of three or four eggs) is
complete. Incubation has been observed to start on the second day
and is performed by the female alone. There is no record of
incubation by the male, and but one observation of a male brooding
a 3-day old nestling (H. R. Ivor Journal). At times during the
incubation period the male feeds his mate both on and off the
nest.
No data on the length of the incubation period in the wild are
available, but we have several measurements from aviary nestings.
A. G. Lawrence reported to Mr. Bent periods from 11 to 12 days in
his aviary. Paul Kuntz (1939) writes from Winnipeg: "The bird
sat steady for twelve days. On the thirteenth two young were
hatched." J. H. Fleming (1903) observed in his aviary:
"About the 16th of July three eggs of a second set were
noticed in the nest; one had disappeared before my return, and on
the 30th one of the two remaining eggs hatched." The
incubation period in this case was at least 14 days. In the Ivor
bird observatory at Erindale, Ontario, the incubation periods for
three marked eggs were 12, 13, and 14 days, respectively.
One of Ivor's birds laid a second clutch; the first egg
appeared when the only nestling of the first set was 11 days old
and still in the same nest. Young birds recently fledged have been
seen as late as mid-August in Ontario and on August 30 in Vermont,
according to Elizabeth Holt Downs. B. M. Shaub (1958) reports a
young male still in juvenal plumage at his Northampton, Mass.,
feeding station on Oct. 26, 1957. These records suggest the
possibility of two broods occasionally in the wild.
Young.--When the young hatch, the
eggshell may be removed by either parent. In one case the female
ate all the shell.
At hatching, the nestling is much like the young of the
rose-breasted grosbeak, but the skin is darker. The little bird
appears very red with damp gray feathers on its head. These
neossoptiles are about a quarter-inch long and dry within 25
minutes. Paul Kuntz (1939) gives his impression of the young:
"They are strong and healthy chicks, all black with a fluffy
down. They looked exactly like young Bullfinches." My own
notes read: "The white natal down sticks out from the top of
the head. The membrane covering the eye looks purplish and very
large. The bill is yellow. The egg-tooth is like the tiniest white
bead on the upper mandible. The gape is white. The mouth and
pharynx have an iridescent appearance--tones of violet and
carmine." My notes for the second day state: "When the
babies are not raising their heads, they throb with every 'peep'
they utter. The natal down is perfectly placed to cover them as a
blanket while in the nest. They lie bellies down. Bellies and
throats are bare, but down grows on head, wings, and tract down
the back."
Parents of newly hatched aviary nestlings at Erindale, Ontario,
fed them a gruel of masticated earthworms and mealworms, which
they first chewed for some time until a dark liquid stained their
bills. We watched wild adults in the Nipissing District of Ontario
feeding the young similarly on the masticated larvae of the spruce
budworm (Choristoneura fumiferana Clem.). When the greenish
bills of the adults become stained dark brown from masticating
insect larvae, it is a sure sign they are feeding their young. The
spruce budworm in all stages of development is the main item of
insectivorous food for nestling evening grosbeaks wherever both
the insect and the bird occur together. Moreover, the birds often
appear for the first time or in unusual numbers wherever there is
an outbreak of spruce budworm during the breeding season.
A number of evening grosbeak stomachs from the collection of
the Royal Ontario Museum of Zoology, including those of juvenals,
were analyzed by J. M. McGugan, Micro-Analyst of the Dominion
Department of Agriculture in Toronto, and Ronald N. Root, of the
U.S. Fish and Wildlife Service. Their analyses showed the most
important vegetable food in the juvenal diet to be the pit of the
pin- or bird-cherry (Prunus pensylvanica). Seeds of other
native fruits such as the hawthorn (Crataegus sp.)
blackberry (Rubus sp.), and blueberry (Vaccinium
sp.) were taken to a lesser extent; also birch (Betula sp.)
seeds. Weed seeds in the diet included those of sedge (Carex
sp.), dock (Rumex sp.), bindweed (Polygonum sp.),
goosefoot (Chenopodium sp.), crowfoot (Ranunculus
sp.), wild geranium (Geranium sp.), and violet (Viola
sp.)
Mr. Bent writes: "Mr. Lawrence has sent me some clippings
from his articles in the Winnipeg Free Press, in which he
describes how the grosbeaks fed their young in the box elder tree
in Selkirk. Both adults helped in feeding the young by
reguritation of semidigested food while the nestlings were too
young to take solid food. It was difficult for the old birds to
insert their heavy bills into the mouths of the nestlings, but his
sketches, based on photographs, show that the adults accomplished
this by twisting their heads to one side. After the young were a
week old they were fed caterpillars and small soft green seeds.
The young were fed at irregular intervals, and, when very young,
were brooded by the female between feedings."
Foraging parents usually, but not invariably, leave and return
to the nest together. When they arrive simultaneously both perch
on the rim of the nest and the female feeds one nestling. Then she
often takes food from the male's bill and feeds another. Finally
the male may give any remaining food directly to the young.
I watched one nest with young 5 or 6 days old in Lauder
Township, Ontario, on June 23, 1945, from 4:45 a.m. until 8:01
p.m. when it was getting too dark to see, except for a half-hour
absence from 6:30 to 7:00 a.m. During this time the young were fed
34 times. Starting at 4:50 a.m. when both parents arrived with
food, there were 14 feeding periods between dawn and noon. For 10
feedings the adults came together or nearly so. Once the mother
came alone and remained to repair the nest lining and brood the
young. Twice the father brought food when the mother was on the
nest, and once unattended by his mate. Intervals between feedings
in the morning varied from 7 to 54 minutes, averaging one feeding
period every 21.5 minutes. Intervals between the 20 feeding
periods from noon to the last one at 7:50 p.m. ranged from 1 to 97
minutes and averaged one every 24 minutes.
The father seemed to attend to the nest sanitation more
assiduously than did the mother; he removed fecal sacs eight
times, the mother only twice. In each case nest sanitation
followed a feeding. The nestling on my side of the nest raised its
uropygium, which was covered with white down, as if to help the
father remove the fecal sac.
Both parents defend the nest and young. On July 4, 1946, at the
Algonquin Park nesting, I watched the pair drive off a gray jay by
dashing at it, giving rough buzzing notes. They treated a bronzed
grackle and a robin in the same manner, and threatened a young
hermit thrush. They tolerated the following species near or even
in the balsam fir that held the nest: golden-crowned and
ruby-crowned kinglets, a myrtle warbler, Blackburnian and Canada
warblers, and a purple finch. They chased no other evening
grosbeaks and seemed tolerant of the few that appeared in the
nesting vicinity.
The young birds grow quickly. An aviary nestling measured 50
millimeters when 51 hours old and 57 millimeters when 78 hours
old. The eyes begin to open on the fourth or fifth day and are
fully open on the fifth or sixth day. The sex of a healthy
nestling can be determined by the ninth or tenth day. Thus H. R.
Ivor wrote in his journal of a 9-day old bird: "The nestling
definitely seems to be a male. The tail feathers have barely
broken and show all black. The white of the middle secondaries are
very pure white."
C. E. Hope found a fledgling male about 12 days old from a nest
in Algonquin Park, Ontario, on July 6, 1946 to weigh 32 grams. A
second young male collected on August 9 weighed 61.5 grams. The
Shaubs have reported on weights of juveniles trapped at their
feeding station at Saranac Lake, N.Y. in the summer of 1952 (Shaub
and Shaub, 1953). "Two females weighed 52.6 and 49.6 grams
respectively. A juvenal male weighed 55.2 grams and an adult male
weighed 51.2 grams."
The young normally leave the nest on the 13th or 14th day. One
fledgling male, that had left the nest prematurely in Algonquin
Park, Ontario, was fed exclusively by its father until
independent. A young aviary male at 36 days from hatching was
being fed from time to time by its mother, although able to feed
itself as well.
Juvenal males have golden heads, and when they raise the crest
to beg for food, as I have seen them do in Muskoka, they are very
handsome. My husband watched a juvenal female with a peach-colored
breast following and begging from an adult in Muskoka on August 5,
1951. The young bird looked as big or bigger than the adult and
had a full-grown tail. Elizabeth Holt Downs recorded the dates of
the arrival of the first young at her feeding station in Vermont
for the years 1953-1957. In 1953, 1954, and 1955 the first young
appeared on June 26. In 1956 the arrival date was July 6; in 1957,
June 17. Juveniles out of the nest have been reported as early as
the first week in July in Ontario. The latest dates of juvenile
feeding is a young male Mrs. Downs saw an adult male feeding in
Vermont the third week in November.
Plumages.--The natal down is
white. The neossoptiles are on the capital tract and on spinal,
femoral, humeral, and alar tracts. Clifford E. Hope describes a
nestling about 12 days old, taken in Algonquin Park, Ontario, on
July 6, 1946: "Pin feathers of forehead, crown, occiput, and
cervix 'clove brown'; back 'olive'; circle of whitish natal down
above eye to nape; bare skin side of neck and center of breast,
dark red; feathers side of breast shading from 'broccoli brown' to
'pinkish buff'; scapulars 'olive'; rump covered with natal down.
Wing: lesser coverts, sepia; middle coverts, black, edged with
gray. Yellow and black feathers with white shafts forming pattern
on inner edge of greater coverts and tertials; yellow mark on
primaries and secondaries. Tail, black; undertail coverts,
whitish. Down on tibia, over pale yellow and black feathers."
Mrs. Downs observes: "The juvenals have a small yellowish
patch composed of the four inner secondary coverts, which I call a
birthmark because they lose it during their postjuvenal
molts." The postjuvenal molt is not complete until the
juvenal is nearly a month old. At 24 days a young male still had a
small tuft of down above the eyes on either side of the crown.
Despite J. Dwight's (1900) statement: "The sexes are
similar in juvenal plumage," I have found that the fledgling
male can be distinguished by its tail feathers; these are usually
black when they break from their sheaths and lack the series of
white spots which characterize the female rectrices. Also, the
male's primaries are black, while the female's are black and
white, and the male has a prominent whitish patch on the inner
flight feathers which the female lacks.
My notes contain the following description of a month-old
female. Crown, occiput, nape, auriculars, and side neck,
olive-gray. Upper mandible, greenish gray; tip greenish. Lower
mandible, pinkish, dark gray at gape. Throat, pale gray, edged
with dark malar stripes. Back, olive-gray. Rump, olive-gray tinged
with peach. Rectrices, with series of white spots near tips.
Undertail coverts, pinkish gray. Breast, light gray washed with
peach. Side and flank, gray tinged with peach. Belly, gray, washed
with pale peach; dark down exposed in places. Wings: fist three
primaries at leading edge, black; the remaining six edged with
white and with yellowish patch forming square on wing. Wrist with
pale yellow edge. Scapulars, olive gray. Greater secondary coverts
with patch of yellow on three feathers, the rest black. Middle
coverts, black, with light edgings. Lesser coverts, black with
olivaceous edgings. Underwing coverts, lemon yellow.
I described a 2-month-old male as follows: Crown and cheek,
"light olive brown." Supra-auricular region "light
olive-brown" with dusky line. Auriculars, "light
brownish olive"; greenish on outer webs. Upper mandible,
"drab," greenish at gape. Throat, "sulphur
yellow." Malar stripes, dusky. Side neck,
"cinnamon-buff." Back, "Saccardo's olive."
Tail, black. Undertail coverts, whitish, tinged with
"cinnamon-buff." Wing, black; inner secondaries and
their greater coverts, white, tinged with pale yellow and edges
with pale buff. Feet, "army brown." At 3 months, the
yellow frontal band of this juvenile male becomes conspicuous. As
the patchwork of black and fawn spread over its crown, the cheeks
were darkening, though not yet of the "bister" color of
the adult.
Mrs. Downs, who has banded so many juvenals in Vermont, writes
me that "there is considerable difference in the color of
juvenal females and juvenal males--body color that is. Both are
tan but the females are a gray-tan and the males a yellow-tan.
Even without seeing their wing markings we can tell a female from
a male by the color of their bodies." (For further
descriptions of the young, see Shaub and Shaub, 1953.)
The first winter plumage is acquired by a partial postjuvenal
molt in the autumn. Of this E. H. Forbush (1929) writes: "the
first winter plumage by partial postjuvenal molt of body feathers
and wing coverts, juvenal flight feathers and tail retained,
tertials may be shed in some cases." J. Dwight (1900) states
that "Young may be distinguished usually by the dusky inner
margins of the tertiaries but differ very little from
adults."
Of the first nuptial plumage J. Dwight (1900) writes that it is
"acquired by wear which removes much of the wing edgings.
Browner more worn remiges and especially primary coverts with
distinct edgings distinguish young birds." According to M. J.
Magee (1928a) some and possibly all evening grosbeaks have a very
slight spring molt. Of 93 grosbeaks he examined between April 15
and May 13, 24 showed signs of molt. These included both adults
and young. The molt was most pronounced on the nape, and one to
several new feathers were seen on crown, occiput, cervix, side of
neck, and throat. We noted a male in partial prenuptial molt at
North Bay, Ontario, as early as Mar. 4, 1944. In 1929, M. J. Magee
(1930) continued his study of the spring molt. On the 50 grosbeaks
he banded from April 13 to May 17, he noted signs of molt on 31.
The molt was largely confined to the front of the head, including
the chin and the neck.
In spring the bill color changes gradually from the winter
"horn-color" (but sometimes "ecru-olive" with
"citron yellow" at the gape, or bright "wax
yellow" or pale pink) to light green or pea green in late
spring, and in June to light bluish green. It is possible to tell
summer birds in collections by the bluish green color of the
bills.
G. Hapgood Parks, who has banded more than 5,000 evening
grosbeaks in Connecticut, wrote to Mr. Bent in 1947: "During
the winter we made a study of the color the birds' bills and
learned that by late February (Feb. 28) the bills began to show
signs of peeling from the tip and edges. An apparent loosening of
the surface membranes gave the upper mandibles of some of the
birds a whitish and swollen appearance across the base of the bill
near the feathers. This latter condition became more apparent on
more birds during the first week of March." In 1951 he added
the following: "The actual color change of the bill is
apparently due to pigmentation. The mottled stage, in which many
bills are seen, bears evidence of this fact. Bills showing no
peeling at all are not infrequently partly green with areas which
retain the 'bone' color typical of the bills in winter. The
peeling off of a colorless surface layer apparently helps to
promote the 'new' polished appearance of the bill.
"The peeling is much more conspicuous on the upper
mandible, although some peeling of the lower mandible also occurs.
I find that my notes about the bills say, most frequently, 'bill
green and peeling.' About as often the entry is, 'blue-green
lower, peeling upper,' or, 'mottled lower, peeling upper.' I feel
certain that the entire surface of the upper mandible peels; I am
not at all sure that the same condition holds for the lower
mandible. I would not dare to say the bills of all of the birds
peel, although I feel very strongly that such is the case."
The adult winter plumage is produced by a complete postnuptial
molt. The earliest date for the beginning of the molt I have noted
is June 28, when a female (one of a nesting pair at the Ivor Bird
Observatory) molted a first primary and the male molted the first
primary of both wings. On August 25 the male's new tail was half
grown. L. H. Walkinshaw (1936) tells of a captive bird that
started to molt on July 16 and did not finish until after November
1.
M. J. Magee (1926b) writes:
. . .After molting, the feathers in the white wing patches
of both males and females are distinctly edged with yellow. All of
the descriptions of the plumage that I have seen, from Audubon
down, are very much as given by Professor Barrows in
"Michigan Bird Life," in which for the the male it is
said "most of the secondaries and their coverts snow
white," and of the female, "primaries and secondaries
black, boldly spotted with white." This limited description
may be due to the fact that only specimens taken in spring were
examined. Practically all of my banding of these grosbeaks had
been done in the spring, until last fall (1925); and then from
November 11 to March 1 I banded eighty-four, forty males and
forty-four females. The males had nearly all the feathers in the
white wing patch edged with yellow on the outer webs, except the
tips. This was true of the great majority of females as well. . .
.
Either from wear or fading the yellow edging lightens; in
the males first on the white secondaries; in the females, on the
white patches of the primaries. This fading of the yellow edging
has been particularly noticeable since the first of March. . . .
According to Dwight (1900) the adult nuptial dress is acquired
by wear.
Food.--The most important native food
for the evening grosbeak is the fruit of maple trees and
especially of the Manitoba maple or box elder (Acer negundo).
A. G. Lawrence of Winnipeg sent the following note to Mr. Bent:
"From fall to early spring the seeds of the Manitoba maple (Acer
negundo) form their chief food, but ash seeds and
chokecherries, both green and dried, are also eaten. They have
also been reported as feeding on low-growing weeds, and on the
buds of the Manitoba maple. They eat snow, scooping it up and
swallowing it in large quantities after feeding on seeds. In
feeding on the maple seed keys, the bird snips off the pod at the
basal end, manipulates the winged portion between the mandibles to
express the seeds from their compartments, swallows or presents
the seeds to a young one and allows the winged pod to flutter to
the ground. The operation is performed so rapidly that the eye can
hardly follow the action."
Winsor M. Tyler (1916) describes in more detail the skill and
precision with which the grosbeaks perform this operation, with
their apparently clumsy beaks. He concludes:
Upon examining the wings which the birds had clipped off, it
was apparent that the birds had bitten directly over the kernel
itself at a point rather nearer the wing than the kernel. But,
although by this incision the kernel was exposed, it was never
severed and allowed to fall with the wing, as would have been the
case had the beak been closed and bite completed. The cutting
process was always arrested at the point after the casing had been
divided, but before the meat had been severed. All this, although
the process involved the nicest precision, was accomplished with
great rapidity, the wing fluttering to the ground within a second
or two after the fruit was plucked from the stem.
E. L. Brereton, of Barrie, Ontario, wrote on Apr. 11, 1937:
"I have always associated the evening grosbeak with the
Manitoba maple and always found them there, the sugar maple seeds
being just a change of diet, but this year found that they prefer
the sugar maple seeds when such can be obtained."
Fred W. Behrend (1946) tells of their feeding habits in the
south. He writes (in part) from Elizabethton, Tenn.:
The budding of the maple trees and subsequent shedding of
the bud scales as winter was on the way out, provided a plentiful
supply of food for the Evening Grosbeaks who seemed to be very
fond of this vegetal matter. . . .
As spring advanced, the feeding habits of the Evening
Grosbeaks underwent, by necessity, a change. No longer did the bud
scales of maple trees cover the ground as they had been cleaned up
methodically in one area after another, and therefore less
frequently were the birds seen on the ground. They now fed on the
fresh seed pods of the maple trees, and most of their time was
spent in the trees. . . .
With respect to the most often referred to favorite food of
the Evening Grosbeak, the seed of the box elder tree, the latter
was non-existent in this community. . . . The writer observed them
feeding on the seeds of mimosa and locust trees, on the hulls
embedding the blossoms of the catawba tree and on the buds or bud
scales of elm trees, all in addition to their most abundant food
in the locality, the bud scales and seeds of the maple tree.
While south in the spring of 1952, we were surprised to come
upon a little flock of evening grosbeaks at Windsor, N.C., on
April 30. At first we saw the birds on green lawns eating maple
seeds. Then we saw several feeding in and under a pecan tree
decorated with green catkins, which they seemed to be eating. At
Yorktown, Va., the next day, we found several in a huge chinaberry
tree and heard the cracking sound as they lived up to their name
of "berry-breaker."
B. R. Chamberlain (1952) quotes from a letter written by J. W.
E. Joyner from Rocky Mount, N.C., which tells of their eating
conifer seeds during the 1952 grosbeak invasion: "When the
birds first came here they were never far from the pines, the
seeds of which were apparently their chief food. Some seed from
tulip poplars were also eaten. . . . In gleaning seeds from the
pine cones they deliberately and slowly plucked the seed out, the
discarded wings floating, rather than swirling, downward. For the
past month they have continued to feed on pine mast but have also
been seen eating elm, maple, and oak buds. They have become
regular visitors to feeding trays, consuming quantities of
sunflower seeds; the seeds going in one side and the hulls
drooling out of the other."
O. A. Stevens, of Fargo, N. Dak., wrote Mr. Bent: "We
usually find them feeding on fruits of Russian Olive (Elaeagnus
angustifolia)." In February 1929, T. M. Shortt saw
evening grosbeaks eating the seeds of the buffaloberry (Shepherdia
argentea), at St. James, a suburb of Winnipeg, Manitoba. The
meaty fruit has a stone in the center, and Shortt told me the
birds were biting the meat off the sides of the stones. Richard J.
Eaton wrote Wendell Taber, that he had "seen these birds
working on hybrid crabapples (Malus sp.?) much after the
fashion of cedar waxwings, pine grosbeaks, and robins." Frere
Marie-Victorin (1935) tells us that in Quebec, the fruits of the
red ash (Fraxinus pennsylvanica) which form in June and
persist on the tree during most of the winter, are a preferred
food of migrant winter birds, including the evening grosbeak. When
evening grosbeaks visited St. John's, Newfoundland, from Nov. 18,
1951, to May 3, 1952, Leslie M. Tuck informs me they fed on the
seeds of snowberry and beech.
Mary S. Shaub (1956) has contributed an important paper on the
effect of native foods on evening grosbeak incursions:
The great adaptability of this species within its winter
range to extremes of climate and topography is evidenced by its
appearance in the Adirondacks, the White Mountains of New
Hampshire, and all the way down the Appalachians to Rome, Georgia,
as well as at many coastal points from Halifax, Nova Scotia, to
Wilmington, North Carolina. It is also most adaptable in its
acceptance of a vast array of native and cultivated seeds and
fruits.
In the course of our study of the Evening Grosbeak since
1947, and in connection with our publishing of the Evening
Grosbeak Survey News during five winters from 1950 to 1955, we
have received a large number of reports dealing with foods eaten
by this species. These are summarized in the accompanying list of
seeds, fruits, and buds. . . .
The box elder is without doubt the most acceptable native
food, and in many reports the Evening Grosbeaks are noted on these
trees and not at feeders, even though sunflower seeds are
available there. This pertains especially to southern Ontario. In
several New York and New Jersey localities the birds were first
noted on box elders and could not be enticed to feeding stations
until the maple keys had been devoured.
Of the numerous fruits taken by the Evening Grosbeaks, they
seem to favor the various cherries, apples, crabapples, and sumac
to all others. . . . Even where the Evening Grosbeaks have settled
down to a routine of daily feeder attendance, now and then for no
apparent reason they will fly off to a stand of sumac for a meal,
or at least a snack, even before the supply of sunflower seeds has
been exhausted. . . .
This variation in diet of the Evening Grosbeak has been
noted over a period of years by Mrs. Gerald Fitzgerald of
Amsterdam, New York, where her fine plantings of Washington
hawthorn, crabapples, red and black chokecherries and cotoneasters
have been attractive to the Evening Grosbeak despite her generous
supplying of over 1300 pounds of sunflower seeds in the winter of
1949-50 and of over 900 pounds during 1954-1955.
Every spring evening grosbeaks may be observed
"budding" in various trees. I have seen them budding in
our elms, in the Rouge Hill area west of Pickering, Ontario. On
Mar. 11, 1958, a female was budding in a tall elm, high up. My
notes read: "She reached for the end bud of a twig, then bit
off each lateral bud. Then to the next twig, taking the end bud
first then each lateral bud within reach on that twig. And so to
the leading bud of the next twig." The following day I
watched two females budding in our lilacs: "Each reached
forward and took the nearest bud within easy reach, bit it off,
ate it and reached for the next nearest bud. These were not
terminal but lateral buds in each case." Mrs. Shaub (1956)
lists numerous different kinds of trees and shrubs in which
grosbeaks have been seen budding.
If tree buds may be considered springtime treats for the
grosbeaks, nature has other delicacies in store for them as well.
Of their fondness for wild maple syrup Thornton W. Burgess (1947)
writes: "Opposite the window of my room is a maple tree.
Squirrels have been eating the buds and when the sun warms things
up in the morning the sap drips from the twigs where the buds have
been nipped off. The other morning the sun striking through these
drops of sap filled the tree with glittering jewels. A male
Evening Grosbeak climbed about parrot fashion from jewel to jewel
drinking them." Mrs. Downs writes me: "Our front sugar
maple tree has been gashed in many places by some creature. Today
I saw the sap flowing from it and the EGs drinking the sap!
Sometimes they even had to 'tread air' to get the sap because
there was no branch handy on which to perch."
As the breeding season approaches, the grosbeaks begin to seek
out insect food, of which the spruce budworm is an important item.
G. H. and H. C. Parks (1963a, 1963b) describe graphically their
studies of a concentration of evening grosbeaks nesting where a
heavy infestation of spruce budworm was damaging the forest in the
Patapedia River watershed of Quebec. In June 1962 using only two
3-cell Potter traps they captured 747 grosbeaks in 11 days. On the
last day of their stay airplanes from the Quebec Department of
Forestry sprayed the area with DDT. Mr. and Mrs. Parks returned
the following June and, using the same traps in the same manner
during the corresponding 11 days caught only five grosbeaks.
During their visit to the same area in July 1964 they could not
find a single evening grosbeak. Parks and Parks (1965) conclude:
To explain the dense concentration of Evening Grosbeaks
which we had originally found at 39-Mile Camp let us call
attention to the fact that repeated sprayings during several years
had been employed in an attempt to gain mastery over a spruce
budworm outbreak which involved forests in New York, Maine,
Ontario, and New Brunswick, as well as in Quebec. Since the birds
no longer found an adequate supply of the budworm for food in the
sprayed areas they moved on to unsprayed tracts where the insect
still persisted.
Examination of the maps on which the sprayed regions had
been plotted shows that the effort to control a particularly
obstinate budworm infestation near Quebec's Gaspe had approached,
but had never quite reached, the Patapedia River prior to 1962.
So, as this "island" of budworm-infested forest (with
39-Mile Camp situated very close to its center) became smaller and
smaller the concentration of Evening Grosbeaks which was attracted
to its abundance of edible larvae became heavier and heavier. Then
1962 witnessed the spraying of even this area and the resultant
successful elimination of the pests which had been damaging the
trees. Come the spring of 1963, the almost completely eradicated
budworm population was no longer adequate to attract and hold more
than a very few of the Evening Grosbeaks which might be returning
to, or migrating through, this area.
Maurice Broun, of Hawk Mountain Sanctuary, wrote Mr. Bent in
1952: "Last May, from the 10th to the 15th, from 20 to 40
evening grosbeaks, remnants of large flocks that visited us during
the winter, were observed in voracious day-long feedings on
cankerworms in the tops of large oaks in front of the Sanctuary
headquarters. The grosbeaks spent more time helping to clean up
cankerworms than they did at the feeders, where the sunflower
seeds became a minor attraction." From analyses of stomach
contents of Canadian evening grosbeaks, J. McGugan states:
"The animal matter of the bird's diet consisted of
individuals of Coleoptera, Araneida, and perhaps
others. The average amount of this material consumed was low but
whole meals were enjoyed when the supply was plentiful."
Salted sand and gravel are sought both summer and winter. The
birds are seen often in summer eating cinders on railroad beds,
tasting the salt-impregnated dirt on gravel roads that have been
spread with calcium chloride to allay summer's dust, or to melt
ice in the winter. Many casualties from cars result from their
craving for salt.
An important summer food is the wild cherry, which is fed to
the young before they leave the nest. To the cherry groves they
are taken as soon as they can fly. The cherries are eaten even
before they are ripe, and cherry pits are sought for on the tree
and later on on the ground until the supply is exhausted. Evening
grosbeaks do not swallow berries whole, as do robins and cedar
waxwings, but always break them, and their massive beaks
accomplish this feat with ease. A flock may be traced to a wild
cherry grove by the sound of the mandibles crushing the cherry
stones. They always discard the fleshy part of the fruit, but
swallow a certain amount of crushed shell with the kernel, which
probably helps them digest their food.
Behavior.--Evening grosbeaks
appear affable and harmonious when not overcrowded or short on
food. When the conditions are reversed, they are not so
attractive. Mr. Bent comments: "Although evening grosbeaks
are ordinarily gregarious and sociable, feeding harmoniously when
scattered openly on the ground, their behavior is quite different
when crowded on the feeding trays. There they are often selfish,
hostile, and belligerent, pushing their way in, sparring with open
beaks, and threatening to attack or drive out a new arrival. They
are bosses of the tray and are intolerant of other species,
driving away even the starlings; only the blue jay seems able to
cope with them. Even the females of their own species are not
immune to attack by the males. But, so eager are they for their
food, that the tray remains crowded full of birds as long as there
is standing room. Towards human beings they are usually tame and
fearless; we can almost walk among them when they are feeding on
the ground; with good treatment they might learn to feed from our
hands, or allow us to pick them up by hand from the feeding tray.
When taken from traps, they should be handled with heavy gloves,
for they can bite savagely with their powerful beaks."
G. Hapgood Parks (1946) writes of his Hartford station:
Why the flock returned morning after morning before sunrise,
its population swelling until more than two hundred individuals
simultaneously crowded every feeder and every shelf and filled
every trap, is at least partly explained by the bushels of
sunflower seed shucks which carpet our partly unspaded victory
garden this spring. Only slightly less appealing to the birds
seemed to be the large wooden bowl which we kept always filled
with warm water. . . . As much as a gallon of water was drunk on
mid-winter days when the Grosbeak traffic was at its height. Not
one of the birds, however, was ever observed in an attempt to
bathe in the bowl.
Later, Parks wrote to Mr. Bent: "We observed our first
evening grosbeak in the act of bathing on January 15, 1947. It was
a rainy day and 12 of the birds bathed briefly in puddles of water
which had formed in depressions in the ice of our driveway. Three
others bathed in the bird bath on sunny, mild January 18. A
half-dozen isolated instances of bathing were observed during the
following weeks."
Forbush (1929) says: "They are fond of bathing even in
winter, and visit unfrozen parts of swift streams at this season
to bathe and drink. . . . ."
Mrs. A. O. Pendleton (B. R. Chamberlain, 1952), writing from
North Carolina, tells of a remarkable invasion of evening
grosbeaks on January 26, 1952, into her garden and her bird bath.
She writes: "We heard a great chattering of birds. . . .
There must have been 500 of them. Surely they must have just come
in from a very long flight because the bird bath was full of them
standing as close to each other as baby chicks, all drinking and
bathing at once. Hovering above the bath like hummingbirds, there
were dozens of them awaiting a vacant spot to alight in the water.
. . ."
Mrs. Lucie McDougall, of Port Credit, Ontario, reported to me
that in late April, 1958, the grosbeaks sunbathed daily at her
feeding station. She saw as many as four males sunbathing at once
on her window-sill, a remarkable sight. Sunbathing grosbeaks
assume most unusual postures. I watched one male sprawled on the
ground looking, it seemed, right into the sun. Its 12 tail
feathers were fanned out so the sun could reach each of them; its
bill was open, its crown feathers erect. Another male cocked his
head sideways, eyed the sun, and seemed bent on having its rays
penetrate the skin beneath the gray down under its breast
feathers.
The evening grosbeak has the undulating flight so
characteristic of the finch family. It does not, however, dip in
such deep loops as does the pine grosbeak, nor does the flight
pattern follow the bouncing bends of the goldfinch. The
undulations are definite but not deep. As a flock moves in flight
in the pathway of the sky, a ringing note, p-teer, p-teer,
is heard with each dip, proclaiming to the listening ear below
that a flock of evening grosbeaks is flying by. We watch the swift
but wavy line of flight, punctuated by wild cries, until the flock
disappears in the distance.
During migration evening grosbeaks fly high. At times their
voices are heard when we are unable to discern the flock in the
sky. Robert Ross Taylor writes me that at Scarborough, Ontario, he
heard the call notes of grosbeaks high over his head flying west
at about 11:00 p.m. on Oct. 6, 1957. During the same autumn, W. W.
H. Gunn heard evening grosbeaks flying high above Toronto in the
very early hours of the morning when he was on a rooftop observing
Sputnik I. The birds were calling and moving westward. In both of
these cases the night was clear. These are the first reports I
have heard indicating that the species sometimes migrates at
night.
Of their manner of flying in wooded country, S. E. White
(Butler, 1892) remarked: "Their flight through the woods is
very swift, reminding one, by the dexterity with which they avoid
branches, of a Pigeon; when in the open, however, it is more like
that of a Blackbird." He also notes that when on the ground
they "move by hopping, holding themselves like Robins, and
turn over the leaves with great dexterity, picking up the seeds
from under them."
Very rarely is the bird ever seen by anyone in the evening. Ada
Clapham Govan (1940) comments: "Where the grosbeaks spent
their afternoons, no one in Massachusetts knew--or why the left
all feeding stations by twelve or one each day."
In April 1940 I received a pair of live evening grosbeaks from
Norwood, Manitoba. After a few days I noticed how early they
roosted for the night. I then noted their times of retirement and
measured the light intensity with a Weston illuminometer. In May
they roosted on an average 45 minutes before sunset, in their
9-foot aviary spruce tree when the light intensity varied between
180 and 60 foot-candles, averaging 135 foot candles. They always
fed heavily before retiring.
As the breeding season advanced, the birds became suddenly
insectivorous. Departing from their usual habits, they looked
continuously for insects. After June 1, although the female might
retire fairly early, the male often kept up his vigilance until
after dark. This might not have happened under natural conditions,
where insects are more readily available than in an aviary.
In autumn I made daily observations. About November 1 the birds
roosted on an average of 57 minutes before sunset, while various
other fringillids in the garden--cardinals, white-throated
sparrows, juncos, and tree sparrows--were still active and
feeding, and robins, starlings, and the icterids in the district
had not yet flown to their roosts. In December, January, and
February the pair often retired shortly after 1 p.m. and hid in
their spruce, sound asleep throughout the afternoon and evening.
Rarely did they ever leave their roosting place unless badly
disturbed.
Evening grosbeaks roost in a variety of places. Edward R. Ford
wrote me in 1942 that in the sand-dune country of northern Indiana
in February: "The temperature must have been near zero and
there was some wind. . . . The bird took its station on one of the
small twigs of a small pine, in the lee of the trunk which was not
more than 5 or 6 inches in diameter. It assumed at once an
attitude of sleep with the head turned to the rear and apparently
resting between the scapulars." Marcia B. Clay (1930) tells
of a male evening grosbeak that passed the night near her house at
North Bristol, Ohio, "on the ground where the slope of the
ravine and the projecting roots of an apple tree afforded
protection from wind and snow." On Dec. 28, 1956, Louise de
Kiriline Lawrence and Sheldon McLaren saw five evening grosbeaks
flying to a roost in white pines at Mattawa, Nipissing District,
Ontario at 3:30 p.m. At 8:30 a.m. on January 31, 1957, Mrs.
Lawrence saw a flock of about 40 grosbeaks at Mattawa, mostly
males, "coming off the night roost in a grove of tall
pines." H. R. Dean of Highland Creek, Ontario, tells me
grosbeaks roosted in white pines and cedars there throughout the
winter of 1956-57.
Lucie McDougall wrote me that on March 31, 1947, she had
"brought an injured bird around" into her house and
released it at 5:00 p.m. It "flew up into a big elm next door
and to my amazement I saw two others up there sleeping." Late
in the evening she went out with a flashlight and found the birds
still there. Again early in the morning the three grosbeaks were
still high up in the big bare elm tree. She told me of other
grosbeaks roosting at Port Credit in a row of tall spruce trees.
We observed several evening grosbeaks roosting in just such a long
row of spruces near Lake Ontario at Oakville on Mar. 2, 1958. We
discovered the birds in the thick crowns of the trees at 3:40
p.m., when a squirrel frightened them into momentary flight.
Voice.--Aretas A. Saunders sent the
following note to Mr. Bent: "In recent years, when evening
grosbeaks have become more frequent in occurrence, I have recorded
some of the sounds they produce, but I am not satisfied that any
of these are songs. The commonest calls are shrill piping sounds,
somewhat suggestive of spring Hylas. These are alternated with a
lower pitched trilly sound. The sounds are like peet peet kreek
peet peet, etc. The peets in my records are pitched on
A''' and the kreeks on F#'''. Another sound that is
occasional is like tchew tchew tchew and is used by birds
feeding in a flock. The pitch is G'''."
Keyes (1888) describes his impressions: "As spring
advanced they were usually seen, especially early in the morning,
in the top of some tree, singing or chattering noisily, thus
attracting the attention of nearly every passer-by. Their loud,
clear, rather harsh, piping notes, uttered in concert, reminded
one forcibly of the familiar chorus of a flock of Rusty Blackbirds
in the spring, and have also been likened to the shrill piping
arising from some frog pond on a quiet summer evening."
Francis H. Allen contributed the following to Mr. Bent.
"The most characteristic call note I describe is a sort of prrrreep,
or rolling whistle, with a clear ringing quality. This note, when
heard in chorus, strongly suggests sleigh bells." Harrison F.
Lewis adds: "A note resembling that of the cedar waxwing,
although somewhat louder. This is uttered when the birds are quiet
and at ease."
Butler (1898) gives the male birds the credit for most of the
noise: "The males have a loud call-note, a sharp, metallic
cry like the note of a trumpet, which they utter frequently when
excited. The females chatter like Bohemian Waxwings." My own
observations force the conclusion that the female is more
loquacious than the male and is often the noisier of the two. Once
when I listened to a pair for half an hour, all the sounds, the
shrill piping grosbeak notes, came from the female.
The call or flocking note, pete or p-teer, is the
most characteristic note the species utters. It is very shrill and
has considerable carrying power, which must help the various
members of the flocks to keep in touch with one another.
Individual birds feeding as units of a widely scattered flock call
p-teer frequently, thus revealing their positions to their
companions.
The evening grosbeak's chirp resembles the house sparrow's and
many times I have been fooled by this resemblance. Sometimes there
is quite a similarity between the grosbeak note and the peet
call note of the robin.
The chorus-song is a purple finch-like chip-chip-choo-wee,
or chip-ip-chu-wee-er. A surprisingly lovely harmony comes
from a mixed choir, as both sexes join in the singing. On the day
that I saw my first evening grosbeaks and heard their music, I
wrote: "Now the grosbeaks are talking together with a tender,
tinkling sweetness, very musical and gentle, a liquid
loveliness."
Usually in March individual males are heard singing their
whisper-song, chip-ip-chu-wee-er. As the season advances,
the phrases are heard many times in full strength and sung by both
sexes. For several years we considered this the true song of the
evening grosbeak. Then, one day in late April of 1941, at the
University of Illinois Vivarium, our male bird,
"Vesper," sang a song which we had not noticed before.
After some introductory passages, he gave a high note that seemed
to come from his nostrils, whizz-whizz-tee-ee. He seemed to
like this new phrase in his musical repertoire and repeated it a
number of times. The tee-ee is very high, yet it carries
well. From then on we detected this song often during his periods
of singing. J. Murray Speirs (1950) writes of a March flock in
Ontario: ". . .if I listen hard I can make out their very
high pitched, rather starling-like squeaky song, Swi-swi-tsiee."
H. R. Ivor writes of a 3-month old male raised in his bird
observatory: "Today I heard him singing--the first time I
have ever heard an evening grosbeak sing. The song was very low
and some of the notes seemed quite sweet, but were intermixed with
some of the harsher evening grosbeak notes. I felt that there was
some resemblance between his sweeter notes and those of the autumn
song of the young rose-breast." The next year, Ivor heard the
same bird singing a song like a catbird's, also some notes similar
to the bluebirds, as well as to the high-pitched notes of the
mating song of the rose-breasted grosbeak.
The warning note of the species, given more often by a female,
is quoit; the scold note is dzee; the male's
invitation to nest, bzzt; the nestling's food-call, see-see-see;
the fledgling's call, bee? bee, bee?, bee, etc.; and the
parent's call to the fledgling that has left the nest is chu-hee-chu,
chu-hee-chu.
Field marks.--The evening
grosbeak is a heavily-built yellow, black, and white finch between
the size of a house sparrow and a robin with a very large,
light-colored beak. The adult male has a brown head and neck, a
black crown and a band of bright yellowish-green over the eyes.
The body is mainly yellow and the tail is short, forked, and
black. The wings of males of all ages are black, each with a
conspicuous large white wing patch. Young males have a golden
crown. The body of the female is gray, suffused with yellowish
green about the nape; wings and tail are black with white
markings.
The flight is undulating, and the black and white wings are
conspicuous in flight. When newly arrived in a locality, they are
sometimes described as "wild canaries," "little
parrots," or "oversized goldfinches." Reports of
orioles seen in the north in winter usually turn out to be this
species.
Enemies.--Evening grosbeaks are
comparatively fearless in the presence of man and have proved to
be attractive and easy targets. The first evening grosbeak known
to science was the specimen an Indian boy shot near Sault Ste.
Marie, Michigan Territory, in 1823 (William Cooper, 1825). When
they appeared for the first time in the east during the great
invasion of 1889-90, D. G. Cox (1891-92) wrote from Toronto,
Ontario, "numbers of them were killed by boys with sticks and
catapults in the streets of our city." This remarkable
tameness contributes greatly to their destruction. His report
concludes: "The birds freely entered the residential parts of
the city. . . . They were quite unsuspicious and tame, and were
unmercifully and wantonly killed with clubs, catapults, revolvers,
pea-rifles, and many were taken alive with a slip-noose attached
to the end of a long stick. . . ." The birds continue to be
attractive targets for the irresponsible young.
In Ontario and elsewhere, evening grosbeaks are sometimes
highway casualties, owing to their previously mentioned fondness
for chlorided gravel with which many of the roads are sanded in
winter.
The domestic cat also takes its toll. M. J. Magee (1932)
writes: "With the number of birds around I found it
practically impossible to keep the cats away. One time I found a
place in a thicket not 100 feet away from my traps where a nice
little 'house cat' had been devouring its kills. Quite a lot of
feathers were scattered around and nine bands were found, two from
Evening Grosbeaks. . . ."
Shrikes, also, are enemies of this species. Mrs. Govan (1940)
writes:
The fifth day of the evening grosbeak invasion dawned as a
smiling but raw winter's day. With snow everywhere, my birds were
awaiting me anxiously. Apparently the grosbeak flock had reached
its peak. . . . At seven in the morning a shrike drove the
terrorized flock before him in a madly dashing wave. . . . Then,
one day, while thirty grosbeaks were feeding on the porch, a
shrike cut across the yard. Shrieking their wild alarm, the
grosbeaks hurtled upward in a blind panic. My last sight of them
that day showed them being followed in close pursuit by the
butcher bird.
Occasionally grosbeaks have been killed by striking the windows
of houses. Often this has occurred at feeding stations when a bird
has been stampeded by a hawk or a shrike.
To date there is but one report of the evening grosbeak
parasitized by the cowbird. Near Saranac Lake, New York, in
mid-June, 1949, a young grosbeak was reported at a feeding
station. B. M. Shaub writes in part: "It was said to be very
much grayer than the previous ones. This young remained in the
tree near the house and was frequently fed by the male grosbeak.
It was not until July 7 that I saw this bird and at once
recognized it as a young cowbird (Molothrus a. ater), at
least a week out of the nest. . . . On July 11 the male grosbeak
and the young cowbird were seen again, but at this time the
grosbeak's interest in the cowbird had greatly lessened and he was
reluctant to feed it and only did so after much begging for food
on the part of the cowbird."
Florence Huestis Simpson gave me an evening grosbeak killed at
a window in Todmorden, Ontario, in March 1958. On it were several
bird lice (Mallophaga) which were identified for me by K.
C. Emerson, who wrote: "The two specimens you enclosed are Philopterus
citrinellae (Schrank, 1776). The long, thin specimen mentioned
in your letter was Bruelia sp. Also found on the host are
species of the genera Myrsidea, Menacanthus, Ricinus,
and Machaerilaemus."
Evening grosbeaks, however, seem to be remarkably free from
bird lice. During the winter of 1945-46, G. Hapgood Parks (1947)
banded 874 evening grosbeaks at Hartford, Conn. "The physical
condition of most of the birds which we trapped was
excellent," he writes. "They were very uniformly plump
and vigorous. . . . Although a quick examination was made of every
bird we were able to discover only one parasite. . . ."
Although the parasite was not identified, he states that its
characteristics "were very similar to those of the common
chicken-louse." A nestling my husband found under a nesting
tree in Ontario in June 1945 had white eggs of a dipterous
parasite in the mouth and on the dorsal feather tracts and also a
deposit of eggs over the left eye.
When Gordon Lambert and Ross Baker collected a young bird not
long out of the nest in the Mattawa region of Ontario, 14
hippoboscids flew out from the bird's plumage. The fledgling was
one of four being fed by an adult, and the nest must have been
heavily infested. J. C. Bequaert has written me that the only
bird-fly taken thus far on evening grosbeaks is Ornithomyia
fringillina Curtis, and adds: "All in all, the fly is
rarely seen on this species of bird and perhaps only of accidental
occurrence on it." He reports (1954) that there have been six
published captures from the eastern race, one of which came from
Alberta (Strickland, 1938) and the others from Ontario. Mrs. Downs
has found these bird-flies on 10 juvenal grosbeaks at her banding
station in Vermont. One was taken from an adult. Most of the birds
she has handled have been free from bird-flies.
C. H. D. Clarke (1934) collected a male in Algonquin Park that
had a tapeworm (Cestoda) in its intestines and microfilaria in its
bloodstream. Of six specimens taken at Brule Lake, Algonquin Park,
in the summer of 1934, he found three, including the one above,
parasitized by blood protozoa, the second being infested by
flagellates of the genus Trypanosoma, and the third by
sporozoa of the genus Leucocytozoon. Wenyon in Hamerton
(1937) also lists Trypanosoma as a protozoal parasite in
this species. Plasmodium, the malaria parasite, has been
reported in a captive bird (Hamerton, 1939) wrongly attributed to Haemoproteus
(Herman, 1944).
Despite these records, internal parasitism in the species is
rare. A. M. Fallis examined blood slides from several banded
Ontario grosbeaks captured in Algonquin Park, 1945-48, and the
smears were negative. Mary S. Shaub of Northampton, Mass., who has
banded so many of these birds, considers them "especially
healthy" (letter). She has written me of another bander,
Dorothy Driscoll of Brookline, Mass., who made blood smears from
grosbeaks during an invasion recently and "found only one
infection in 100 smears."
Age.--As yet no one has analyzed the
wealth of banding data now available to determine the evening
grosbeak's probable longevity or its rates of mortality and
survival in the wild. M. J. Magee (1939) reported retaking three
of his banded birds in their 9th year. Elizabeth Holt Downs at her
home in Vermont banded a grosbeak July 11, 1956 as an adult
female. This bird returned regularly and was at least 10 years old
when she recaptured it June 10, 1965.
H. R. Ivor probably has the longevity record for an aviary bird
of this species. Some years ago he received from Winnipeg a
handsome adult female of unknown age which he named
"Beauty." I knew the bird well. She lived in his bird
observatory 16 1/2 years and was therefore at least 17 years old
when she died.
Fall.--In the autumn, adults and
young are "on the move." Their long wings--longer in
relation to body-size than any other finch--make them well
equipped for extensive journeyings. Until recent years, little was
known about this bird's habits in the fall; but since it has moved
eastward as a breeding species, it has been appearing in populated
regions in some years, notably in 1957, early in the fall, and is
therefore being observed more frequently. The birds show no
interest in feeding stations at this time and are reported more
often in box elder trees than in any other kind. K. F. Edwards
reported on Grand Manan Island, New Brunswick, October 11-16,
1957, a flock of 15 was feeding on cherry pits, another favored
food. Louise de Kiriline Lawrence saw five on Oct. 19, 1944, at
Rutherglen, Ontario: "They were eating cone seeds in the tops
of coniferous trees." On November 14, she watched two settle
in an aspen and sample the buds. On Oct. 27, 1947, she saw others
budding in a poplar. Thus, on occasion, this species is a fall as
well as a spring budder.
Winter.--Mr. Bent has written:
"It is when the grosbeaks come to our feeding trays in winter
that we become intimately acquainted with them and their traits.
For a number of years I have maintained a feeding shelf at my
study window, almost within an arm's reach as I sit at my desk,
and have kept it supplied with sunflower seed, hemp seed, cracked
nuts, peanuts, scratch feed, and other mixed bird food.
"During winters that they are here they flock to the
shelf, often in such numbers that there is hardly any standing
room; as long as there is room for one more to crowd in they come
and gobble up the food, with a decided preference for the
sunflower seeds; these they crack open very skillfully with their
beaks, swallow the kernel and let the shells fall where they may,
which leaves quite a mess for me to clean up. When the grosbeaks
are here in large numbers they consume an enormous amount of these
seeds, involving considerable trouble and expense to keep the
greedy birds satisfied, but they are worth it.
"Francis H. Orcutt, of Penn Yan, N.Y., writes to me on
this point: 'Other bird students with feeding stations report that
the grosbeaks are eating them out of house and home. At first, one
or two birds began feeding, now I have 40. With sunflower seeds at
49 cents a pound, I cannot afford to feed them much longer.'
"During some winters these birds are seen in enormous
numbers, hundreds or even thousands of them; some seasons, we see
only a few, and in other years none at all. Probably the abundance
or scarcity of food supply may explain this irregularity."
Mr. Bent refers the reader to: Butler (1892), Elon H. Eaton
(1914), Arthur H. Norton (1918), Bagg and Eliot (1937), and
Brackbill (1947) for records of invasions of this race from
Wisconsin to New Brunswick, in the years since the discovery of
the species. For a very complete picture of the years 1950-1955,
the reader is referred to "Evening Grosbeak Survey News"
edited by Dr. and Mrs. B. M. Shaub, which tells of the penetration
of the grosbeaks south to Georgia.
Some winters, as in 1956-57, the grosbeaks stay north and only
a comparatively few appear south of the 45th parallel. The evening
grosbeak is well equipped to resist the cold, for beneath the
contour plumage is a warm gray down. It wears its own
"eiderdown" for the same reason that the eider duck
wears his--insulation against the cold. The feet are very short,
so short that they may be tucked under the feathers in cold
weather. The unfeathered part of the leg is covered in the front
with scales or scutellae. The underside of the feet, including the
toes, are padded with tylari, corneous cushions in ridges, which
give the feet grip on icy branches, leading J. Murray Speirs to
comment: "The grosbeaks are equipped with their own snow
tires."
One morning in North Bay, Ontario, when the temperature was 35o
below zero, anxious to find out what the grosbeaks did on an
extremely cold day, I went out. A flock of 12 were located,
feeding on Manitoba maples. Above each bill, the breath of the
bird could be seen like a little wreath. All were males. My notes
read: "I noted that they looked noticeably larger than usual,
as their feathers were fluffed out as far from the body as
possible, so that they were encased in warmth. Their feet were
tucked into the warm down and could not be seen at all. One of
them reached far out for a pair of the winged seeds, and broke
through the silver ice, with which the seeds were encrusted, with
a loud snap. In spite of the icy frosting over the trees and
seeds, apparently they were getting all the food they needed, and
even piped prettily, choo-wee, chorr-wee, to each
other."
Evening Grosbeak*
Coccothraustes vespertinus [Eastern
Evening Grosbeak]
Contributed by Doris
Huestis Speirs
*Original Source: Bent,
Arthur Cleveland and collaborators (compiled and edited by Oliver
L. Austin, Jr.). 1968. Smithsonian Institution United States
National Museum Bulletin 237 (Part 1): 206-237. United States
Government Printing Office
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