Agassiz Association. Wilson Ornithological Chapter.

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xanthocephalus) .
The Yellow-headed Blackbirds were by far the most
abundant breeding form of the swamp. In the part examined
there were probably several hundred nests; in the remaining
half of the sw^amp the number is only a matter of conjecture.
The nests which we examined were practically identical in
location, being built in the wild rice growing some distance
from the shore. They were woven in basket shape about
three or more stems from eighteen inches to two and one-half
feet above the water. The water in the region of the nests
was about hip deep and they seemed to be confined to a belt



56 The Wilson Bulletin — No. 87

of this depth around the part of the swamp studied. This
lay quite close to the south and east shores and was, as far
as our investigations exteiided, the deepest part. A belt of
water of this depth about one hundred yards Made lay in a
half moon shape along these shores while the center was much
shallower, being in many places not over eighteen inches deep.

The period of nidification was represented in the colony in
nearly all of its stages from nests in which the clutch was
not yet completed to almost fully grown fledglings. The
cries of the young could be heard on all sides but it w^as
difficult to distinguish one from his surroundings after he
was in the weeds. One of the surprises of the study was
that of learning the extremely early age at which the young
left the nest. In the first ])rood studied, the young left
before the end of the first day's observations. At the time
they were in the pin feather stage of development and very
few of tlie feathers had even begun to show beyond the
sheath. That these nestlings did not leave any earlier on
account of the blind was proved by the finding of a number
of others in the same stage sitting on the broken down reeds
scattered through the swamp. It seemed to us at first as if
the obscurity of the reeds was much safer for the young than
the nests, which were at times rather conspicuous, but later
developments served to shake our faith in this explanation.

On the morning of June 29 at 4 :00 A. ]\I. the blind, erected
between the Blackbird and Bittern nests, was entered by Mr.
Howard Graham and the writer. Watch was kept on both
nests and we soon had proof that the parents had not
deserted them. The female Yellow-head fed one of the nest-
lings at 4:35, or about thirty minutes after the blind was
entered. Constant observations were carried on until 4:30
P. M., at which time the wind blew the reeds about so violently
that it was impossible to see either nest more than a fraction
of the time. The action of the wind also made it difficult to
see out of the opening in the blind at all times, so the work
was closed for the day. This nest will be called nest A.

July 3 the blind was placed in position at another YelloAV-
head's nest containing three young. The work was begun at



Bird Study in a Nebraska Swamp 57

7:30 A.M. on July 4 and continued until 4:30 P.M., when
observations were again stopped by the wind. At the end of
the day the blind was taken back to the Bittern's nest to
continue the work there. This nest will be referred to as
nest B.

In spite of the comparatively small amount of data secured
in these two short studies, several facts were noted. In both
eases the female did all the feeding, neither male approaching
the nest. The males were apparently in little fear of the
blind as they sat in the weeds only a few feet from it and
uttered the harsh notes characteristic of the species. On
several occasions the chosen perch was one of the stakes used
to anchor the boat. This of course does not prove that the
male never feeds but it is worthy of record that with scores
of Yellow-heads of both sexes feeding and foraging about the
blind we never saw a male carrying any insects away
althougli many females were often found to do so. The
males were seen hunting but always promptly devoured the
insects caught. The total number of feedings recorded was
thirty-eight for nest A and twenty-five for nest B. Table I
will show the character of the food given to the two broods.

TABLE I.

Nestling Food ix Nests A and B.

Food. Nest A. Xest B. Total.

Unidentifieil *lo 1 16

Dragon fly ^ 4

Larvae i 4

Mayfly 27 19 46

Grasshoppers 4 4

Totals 50 24 74

The amount of data here presented is too small to permit
of any conclusions concerning the food of the nestlings of
the species and yet several important facts are revealed by
the study.

*An attempt to continue the observations after the wind became bad
explains the large number of unknowns. At nest B the blind was closed
as soon as the wind made it impossible to see the nest.



58 The Wilson Bulletin — No. 87

It will be noted that mayflies constituted 62.16 per cent of
the total and it is not improbable that most of the sixteen
unidentified forms were also mayflies as the blowing about of
the reeds prevented our determining the insect fed. This
evidence tends to support strongly the statement made in a
previous paper* that the food of the nestlings is largely
determined by the accident of nest location.

The surroundings of these nests presented no variety. For
a considerable distance about the nest, the conditions of shade,
moisture, vegetation, and temperature were the same, and
the insect species were of course limited to those forms
favored by such conditions. As far as we could discover,
mayflies and dragon flies were the only forms commonly
found. These were clinging to the stems and leaves of the
aquatic plants and the blackbirds secured them from these
places. They seldom went far from the nest in their hunting
and much of the time we could see them climbing about
picking up insects until two or three were captured, when
they flew to their nests with them.

In the sanitation of the nest the same care was found as in
other species, the excreta never being allowed to touch the
nest. It was taken directly from the young and carried away.
It was rarely devoured, being disposed of in this manner
only once in the two days. In nest B the three nestlings
received about equal shares, being fed nine, eight, and seven
times, respectively. The one which received the greatest
number of feedings died in the afternoon and was carried
away by the female on the last visit at 3 :51 P. M. In nest A
the young left the nest during the day and of course no com-
parison between their food is possible.

The method by which the young left the nest was inter-
esting. At 5:38 A.M. one of the young clambered to the
edge of the nest, seized one of the supporting reeds with each
foot and climbed up them a short distance above the nest,
advancing each foot alternately. After going about eighteen
inches, the bending of the stalks under his weight brought

*Nest Life of the Catbird. Dumetella caroUnensis. By Ira N.
Gabrielson. Wilson Bui., Vol. XXV, Dec, 1913,



Bird Study in a Nebraska Swamp 59

them in contact with others onto which he went. After
traveling in the tops for a little way, he commenced to work
toward the water, and reaching a broken reed rested a while.
In a few moments he proceeded along this reed to another
and was soon out of sight. The second nestling left at
7 :00 A. M. in the same manner, and the third started several
times but returned and was still sitting on the edge of the
nest when the blind was closed for the day.

I had one glimpse of some of the dangers to which the
young Yellow-heads are exposed. One of the young from a
neighboring nest was sitting on a reed about two inches above
the water when the jaws of a hungry pickerel rose from the
water and the nestling disappeared. It was done so quickly
that if I had not been looking directly at the bird it would
never have attracted my attention. It is probable that others
meet the same fate. Several times I noted fledglings that had
just left the nest fall into the water. They managed to
crawl out on a convenient reed but some may lose their lives
in this way.

RED-WINGED BLACKBIRD. (Agelaius phoeuiceus phoeniceus).

During the season of 1913 the Redwings were few in
number, only four nests being found in the part of the
swamp examined. As a usual thing the nests are placed in
the flags or cat-tails, but all of these were in small willows
from three to eight feet high, growing just in the edge of
the water. No others of this usually abundant species were
noted, and apparently the four pair were all that were in the
southeastern half of the swamp. In all swamps where I have
found both of the marsh blackbirds the same distribution has
been noted ; i. e., the Yellow-heads occupied the body of the
swamp and the Red-wings the edges. As far as my experi-
ence goes the former always builds over deep water. The
latter, however, is more variable, building along the edge or
farther out in the swamp indiscriminately when the Yellow-
head is absent, and occasionally nesting in fields quite remote
from any water.



60 The Wilson Bulletin — No. 87

At noon on July 3, a small blind was erected at a Red-
wing's nest which contained four yonng. The nest was dis-
covered Jnly 1 and held at that time three young and one egg.
At 2 :30 P. M. of the third, an attempt was made to begin the
study but the birds had not yet become reconciled to the
presence of the blind and would not approach at all. At
7 :30 A. M. of the fourth, observations began and were con-
tinued until 4:30 P.M., when the high wind began to inter-
fere to such an extent as to make further work unproiitable.
As we approached, the male greeted us with his "Con-qua-
ree" from the top of the blind, and he continued to use it
during the day as a perch, either hopping about the top or
swinging on one of the guy ropes. The female did all the
feeding throughout the period of observation, the male con-
tenting himself with watching the nest from one of his
perches on the blind. At the approach of any person he left
his perch and circled about his head, keeping it up until he
had passed some distance beyond the nest.

During the day the young were fed fifty-one times. One
of the four was dead at the time the work was started but
remained in the nest until 3:00 P.M., when the female seized
it and carried it away.

TABLE II.

Food of Nestling Eed-avinged Blackbirds.
Food. Number.

Unidentified 12

Wirewoi-ms H

Cricket 1

Beetle 3

Mayfly 2

Fly 3

Green worms ^

Grasshopper 20

Moth 3

Spider 1

Tomato worms ^

Measuring worm 1

Total 76



Bird Study in a Nebraska Swamp 61

The noteworthy thing about these data is the great variety
of food used. Apparently the factor of nest location has
again been the one which determined the nestling food. The
conditions of shade, soil, vegetation, and moisture are varied.
The nest was located at the water's edge, and at this point
the land sloped I'apidly up from the swamp and was covered
by a heavy growth of willows and wolfberry bushes. There
were at least four readily distinguishable zones in which the
conditions mentioned varied : first, the water surface, filled
with flags, arrowhead lilies, and, further out, cat-tails and
wild rice, furnished mayflies, dragon flies, with an occasional
grasshopper; second, the shore line, a zone of from three to
five feet in width covered with decaying vegetation and bits
of sticks, contained principally beetles and crickets; third, a
narrow strip of grass covered territory lying between the shore
and the bushes; and fourth, the bushes. The last two zones
contained great numbers of insects of various species with
grasshoppers the inost numerous. These two furnished the
greater part of the insects fed and seemed to be the favorite
hunting ground of the female. The result of these varying
conditions is the use of a variety of species as food instead of
practically only two or three as the Yellow-heads did. The
Red-wings foraged within a comparatively small area about
the nest. The female never- became quite reconciled to the
presence of the blind and always came to the nest in a quick
nervous way and, after inspecting it, fed hurriedly. The
young did not raise the posterior end of the body in voiding
the excreta and the parent was compelled to probe in the
nest for it. Always on leaving the nest the female uttered a
call much like that of the cowbird and one that I never
before had heard a Red-wing use.

AMERICAN BITTERN (Botuurus Untiginosus) .

As far as we could discover tliere was only this one pair
nesting in the swamp. The nest, which was discovered on
June 28, contained five young several days old. The nest
was built in water about three feet deep in a heavy growth
of I'ushes. It was simply a floating platform of reeds with



62 The Wilson Bulletin — No. 87

no attempt to make a nest depression in the top. It was
loosely woven about several upright stems which served to
anchor it in place. Leading away from the nest were two
distinct paths which ended from twenty to thirty feet away.
The parent never flew directly to the nest but dropped into
the end of one of these paths and came stalking cautiously
to it. In leaving she always followed the other path and
took wing from the end of it. The paths were marked by a
broken and trampled line of vegetation and ended in a small
platform. Our boat was placed directly across the path for
leaving, and we had an opportunity to watch the building of
a new one. On the first visit noted she walked off through
the wild rice to the east of the nest, grasping the upright
stalks with her feet and climbing from one to another. Her
weight broke numbers of them and made the beginning of
the trail. After going about twenty-five feet, she commenced
to break other stalks down and lay them in a pile. Some
were already in the water and she soon had a platform
capable of sustaining her weight. The reeds were seized in
the beak and broken with a quick sidewise jerk of the head.
When the platform was finished, she stepped upon it and
stood there for a time before she flew away.

During the watch on the twenty-ninth we saw her feed
only once and then did not get to see the entire process as
she entered quietly while we were watching the blackbirds
and had nearly finished feeding when we noticed her. We
were afraid the young would suffer for food on that day and
undertook to feed them. If there was one conspicuous thing
about the life in the swamp, it was the frogs — little fellows
some of them with the remains of a tail still visible. The
shore from three to five feet from the water's edge was
simply carpeted with them and a person walking along the
shore apparently sent almost the entire surface leaping into
the water. It was an easy matter to secure a number with
the aid of a stick, and we soon had between fifty and sixty in
a couple of cans. When these had all disappeared down the
five gaping throats in two feedings, about an hour apart, we
thought we understood the necessity for such great numbers



Bird Study in a Nebraska Swamp 63

of frogs. As Graham remarked, "It's a good thing tliere is
such a fine crop of frogs and only this one Bittern family
around. If the frogs were any less or the Bitterns any more
plentiful, there would be a famine in the Bitteru tribe."

Only the female came to the nest, although the male was
often heard "pumping" in the surrounding reeds. We noted
one fact in connection with the Bittern's hunting not noted
in any other bird studied, and that was the distance from
the nest of the regular hunting grounds. All other birds
studied forage in the immediate vicinity of the nest while
the Bittern went across the end of the swamp at least a half
a mile from it. The nearest shore line and the place where
we obtained the frogs was not more than a liundred yards
away and the frogs fairly swarmed there. She was never
noted feeding along this shore but flew across the swamp to a
grass grown point covered with about two inches of water.
One day I went around to this point and concealed myself
in the willows to watch while Mr. Graham remained in the
blind. The Bittern soon came flying from the direction of
the nest and dropped into the grass a short distance from me
and immediately became stationary. The frogs, which were
as thick here as on the other shore, soon forgot her presence
and began to swim about or climb over the bogs. When one
came within reach, out shot the long neck and beak and seized
him. He was hammered against a bog a few times and
swallowed. After securing a number in this fashion she
stepped up onto a bog and went to sleep. After a short rest
she flew a little waj's down the shore and went to hunting
again. After her hunt and rest this time she flew heavily
across the swamp toward the nest. Her disinclination to
hunt on tlie nearer shore probably arose from the fact that
it was frequented by boys much of the time and not from
any aversion to hunting near the nest.

It was not until July 1 that we secured a good description
of the complete feeding process. The following extract is
from the note book used on that occasion: "At 9:55 A.M.
I heard the flapping of heavy wings and the female settled
down into the rushes about twenty feet from the nest. She



64 The Wilson Bulletin — No. 87

consumed ten minutes in covering that distance, advancing a
few steps and then remaining "Motionless for a time. When
only four or five feet away, she stopped for five minutes,
remaining, as far as I could see, absolutely motionless, and
then, apparently satisfied, stepped up to the nest. She pro-
gressed by grasping the upright stems of the aquatic plants
and when she stopped to listen looked as though she were on
stilts. As soon as she reached the nest, the young commenced
jumping at her beak, continuing this until one succeeded in
seizing it in his beak at right angles to the base. A series of
indescribable contortions followed, the head of the female
being thrown jerkily in all directions and the muscles of the
neck working convulsively. Finally her head and neck were
placed flat on the nest for several seconds and then slowly
raised again. As it came up the food came slowly up the
throat into the mouth. As the food passed along the beak,
the open beak of the young bird followed its course along
until it slid into its mouth and was quickly swallowed. The
young one then released his hold and the parent stood with
the muscles of the neck twitching and jerking. The remaining
young kept jumping at the beak until one secured a hold
on it, when the process was repeated. By 10:30 all five of
the brood had been fed. Each one after receiving the food
staggered across the nest and lay down with the head and
neck flat on the weeds and remained in this position for some
time before showing any signs of life again." After the
feeding the parent walked away and built the platform
described elsewhere. She rested here until 11 :15 and then
flew away. On the sixth of July the young had become well
feathered out although the natal down was still conspicuous
on the head and neck. It was impossible to do any more work
with them after this time as they began going out in the
swamp to meet the parent, receiving the food there and
returning to the nest. On July 1 the nest was under observa-
tion from 8:00 A.M. until 4:30 P.M. and the young were
fed three times during that period, making from five to eight
feedings the probable number for the day. Each time all
five young were given a mass of food about the size of an



Bird Study in a Nebraska Swamp 65

English walnut. In its quick passage from the parent to the
young it was not possible to determine much as to its nature
except to discern an occasional frog's leg. When last noted
they were still being fed by regurgitation. It would be inter-
esting to know how long this method of feeding is continued
but we were unable to follow the fortunes of this Bittern
family any further.

An observation made in 1910 may be of some interest in
this connection. While a piece of wild hay was being cut,
a nest of this species was uncovered and four of the five
young were killed before the team could be stopped. A small
patch of hay was left standing about the nest and the young
one placed in it. At this time he was fully feathered out
but was unable to fly. The next day the parent was noted
flying into the patch of hay without anything in her beak.
After she left I walked over and approached the young one,
who immediately started to run. Seeing that he could not
escape he stopped and disgorged the contents of his stomach.
An examination showed one garter snake about sixteen inches
long, a meadow mouse and three cra;yfish, all partially
digested. This observation seemed to prove that at this age
the young were still being fed by regurgitation.

During the time the nest was under observation, a number
of interesting facts were noted in connection with behavior.
One thing which struck us very forcibly was the apparent
readiness of the parent to abandon the young at the approach
of any person. She made no attempt to defend them but
stalked stealthily away at any slight noise or movement.
This made it necessary to sit absolutely motionless in the
boat while she was at the nest and as she frequently remained
for an hour or more it became decidedly uncomfortable. Any
slight movement would cause the boat to tip and at this she
was gone in a flash. Several times she approached to within
a few feet of the nest and was frightened away by some
slight motion of the blind. On these occasions she generally
remained away for from three to four hours. This is not
always true of the Bitterns as I have liad them remain on
the nest and almost allow me to touch tliem and have had



66 The Wilson Bulletin — No. 87

them try to frighten me away by ruffling up the feathers
and making a funny hissing sound.

The actions of the young were very interesting and were
in direct contrast in many ways to all other young birds
with which we were familiar. No sound was ever made on
the approach of the parent beyond a slight hissing, barely
audible in the blind four feet away. This was very different
from the young Yellow-headed Blackbirds on all sides of
them, who could be heard almost constantly begging for food.
During the absence of the parents, however prolonged, no
outcry M'as ever made by the young Bitterns unless one of us
went out of the blind and tried to touch one of them. When
we did this they backed away from us, uttering a curious
hissing sound and pecking viciously at our fingers. It was
interesting to note the change in their actions after the parent
left the nest. For perhaps ten minutes they remained in the
position assumed after feeding, as described above. At the
end of that time they commenced to raise their heads and
look around. For the next hour they sat contentedly on the
shaded side of the nest, occasionally dipping the tip of the
beak into the water but never drinking anything. In the
next half hour they began to grow uneasy and to keep watch
for the parent. Every blackbird that flew above the nest
caused each head to rise to its full height and silently watch
his flight across their horizon. At times they seized each
others' beaks in the same manner as the parent's was held.
At other times they seized the reed stems crosswise and pulled
vigorously on them, sometimes working the mandibles as if
chewing. This continued until the return of the parent,
when all would assemble on one side of the nest and watch
her approach through the reeds. No sanitary measures were
noted, and the nest became a rather unpleasant smelling
place before our work was finished.

LEAST BITTERN. (IxohrycJius exiUs.)

The Least Bittern nest, which was located on June 26,
contained five eggs. On July 4 two eggs had hatched and
on the sixth all but one. The blind was put in place on the



Bird Study in a Nebraska Swamp 67

evening of the sixth, and we watched this nest most of the
day on the seventh. In marked contrast to the timidity of
the Bittern, these birds were devoid of fear. Wliile we
hauled the boat and blind in place and drove stakes to anchor
it, the female sat quietly on the nest. And when we removed
the blind, the male gave an exhibition of equal fearlessness
by sitting on the nest through it all and pecking angrily at
our fingers when we tried to touch him. On July 7 at 8 :00
A.M. I entered the blind. The female was on the nest and
did not leave until I stepped into the boat, causing the blind
to tip suddenly toward her. At this she stepped off from the
nest and walked some five or six steps. After remaining there
watching the blind for about thirty minutes she returned.


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