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Marsh Wren
Cistothorus palustris
[Prairie Marsh Wren]
[Published
in 1948: Smithsonian Institution United States National Museum
Bulletin 195: 248-259]
***
The prairie marsh wren is naturally not evenly distributed
throughout its wide range. Marshes of the type it requires are
often widely scattered, or entirely lacking over large areas.
Small, isolated marshes of less than an acre in extent are usually
avoided, but where the larger marshes contain suitable vegetation
the wrens may be very numerous and their nests more so.
The favorite haunts of the prairie marsh wren are the large
freshwater marshes of the interior, where there is a dense growth
of cattails (Typha angustifolia and T. latifolia),
bulrushes (Scirpus lacustris), sedges (Carex), or
wild rice (Zizania aquatica), which are often mixed with
tall marsh grasses of various kinds, or with a scattering growth
of button bush (Cephalanthus) and other small bushes. In
eastern Massachusetts we sometimes find them along the banks of
tidal rivers, where the water is brackish and where there is a
thick growth of tall reeds and salt-marsh grass. I have found
them, also, in pure stands of wild rice bordering a sluggish
inland river.
Dr. Charles W. Townsend (1905) tells of a large marsh in Essex
County, Mass., in which "the growth of rushes and grasses is
rank and tall, and among these a multitude of Long-billed Marsh
Wrens live and build their nests. The rush-like plants in which
they breed are chiefly as follows, belonging to several widely
separated families: great bulrush (Scirpus lacustris),
horse-tail (Equisetum limonsum), sweet flag (Acorus
calamus), blue joint grass (Calamagrostis canadensis),
reed canary grass (Phalaris arundinacea)."
Spring.--Very little seems to be
known about the migrations of the marsh wrens. Elon H. Eaton
(1914) says: "Evidently they migrate at night, and high in
the air, so as to see their way and escape their enemies more
successfully." They arrive in central New York from May 4 to
16.
Dr. Wilfred A. Welter (1935) has given us such a fine life
history of the prairie marsh wren, based on extensive observations
at Ithaca, N. Y., and at Staples, Minn., that I cannot do better
than to quote from the results of his work. At both places he
found that the average date for the arrival of the males was May
10 and that the females came between May 20 and 28. Males begin to
select and defend their breeding territories soon after their
arrival. He says:
The preferred habitat is not, as one might suppose, a dense
tangled mass of dried and broken cattails, remnants of the
preceding season, but a comparatively open area with a few
tattered stalks and an abundance of some species of Carex.
. . .
Fighting over territorial rights between males is, to a
large extent, a matter of out bluffing the opponent. A male
approaching too closely to the boundary of another's area is
challenged by the song of the rightful owner. This is usually
sufficient for the intruder, but sometimes the challenge is
accepted by the visitor giving voice to his emotions and
continuing to transgress upon the area in question. The first male
in this case fluffs out his feathers to impress the other and, if
necessary, flies at his opponent. The usurper usually reciprocates
by flying at his neighbor a time or two and then, at least in all
instances observed, becomes the vanquished and departs from the
scene of battle. . . .
In an area 400 by 650 feet in the Renwick Marsh at the head
of Lake Cayuga eight males took up residence in the spring of
1931. . . . The cattail-sedge association was greatly preferred to
the grass association by the male birds in selecting territories.
. . . Typha angustifolia is much preferred to T.
latifolia as a nesting site. . . .The male territories in the
favored area were noticeably smaller than in the grassy area. A
single monogamous male occupied a territory of from 13,000 to
15,000 square feet, while in the grass association this was
extended to approximately 30,000 square feet. The territory of a
polygamous male, on the other hand, was considerably larger than
that of a monogamous male nesting in the same sort of vegetation.
. . . This difference in size can readily be accounted for by the
fact that the female birds do not tolerate each other during the
nesting season. As a result those males intent upon leading dual
lives must separate the objects of their affection as widely as
possible.
Courtship.--The courtship of the
marsh wren is expressed in song and in display. According to Dr.
Welter (1935), "song does not seem to be as important in
attracting the female as display. Of course the song originally
attracts the prospective mate into the territory and then display
becomes first in importance. When the females begin to arrive from
the south the males sing almost constantly." The songs at
this time often average about 25 per minute, but during nest
building the songs are less numerous and the intervals between
singing periods become longer.
"The display of the male is quite simple but interesting.
when the female is near he will take up his station at a foot or
two above her, fluff out his breast feathers and under tail
coverts, and jauntily cock his tail over his back so that it
almost touches. He now resembles a tiny ball of feathers perched
among the reeds. As he becomes more animated he beats his
partially folded wings up and down rapidly and sways his head
dizzily from side to side. The female probably will fail to notice
him, or at least she will not indicate any interest, and, after
pursuing her and displaying for several minutes, he will burst
into song and fly to another portion of the territory."
The sexual organs of the male are well developed when he
arrives, but those of the female are not, so that she has to avoid
him until she is ready. Dr. Welter continues:
During the period of nest construction she reaches the
height of her development and is ready for the mating act. When
the male approaches her at this time, singing, she climbs up a
cattail stalk and gives the trill which has already been
described. Then she beats her wings rapidly, points her bill
toward the zenith, and places her tail well over her back. The
male goes through the courtship display previously described. At
the proper time he climbs upon the back of his mate, beats his
wings rapidly as the cloacae come in contact and copulation is
completed. The whole procedure takes but a few seconds. Both
remain in the immediate vicinity for a short time, the male with
feathers fluffed out and tail up, the female quiet and demure.
It is usually the male who tries to induce the female into
copulation but on one occasion the female was observed going
through the behavior leading to the mating act to entice the male.
In this instance the act had been completed 25 minutes previously.
The male, not giving the proper response, was chased by the female
among the cattails and it is not known whether she was successful
or not.
Dr. Welter believes that the male is "essentially
polygamous while the female is not." Several of the
territories were inhabited by one male and two females, and in one
doubtful case it was thought that a male had three mates. There
was another doubtful case of polyandry, where a female had no
regular mate, and her nest was placed between the territories of
two mated males.
Nesting.--The prairie marsh wren
nests in wet marshes, where the water is from a few inches to 2 or
3 feet deep, along the banks of tidal rivers where the water is
brackish (in Massachusetts), along sluggish inland streams, around
the shores of ponds, and in inland marshes or sloughs. It seems to
prefer to build its nest in the narrow leaf cattail (Typha
angustifolia), seldom using the broadleaf species (T.
latifolia). Early in the season, before the green flags have
grown to sufficient height, I have found the nest in some thick
bunch of the dead flags of the previous season, but the new green
flags are much preferred. The nests are usually placed 1 to 3 feet
above water, seldom higher, and are securely fastened to two or
more stems of the cattails.
Nests are less often placed in bulrushes (Scirpus),
sedges (Carex), wild rice (Zizania), tall marsh
grasses, or even small bushes. In North Dakota we found these
wrens nesting around the edges of the sloughs in either dead or
green cattails, or in the bulrushes. Near Lake Winnipegosis,
Manitoba, we found a nest firmly attached to the canes of
bulrushes, 4 feet above the water; it was within 4 feet of a
canvasback's nest and was lined with down from the nest of the
duck. The nest is said to be shaped like a coconut, or globular,
but some that I have seen have been egg shaped with the pointed
end at the bottom. The entrance is a small round hole, usually
near the top.
Dr. Welter (1935) gives an elaborate account of the building of
the brood nest, which is done almost entirely by the female, and
which requires 5 to 8 days, beginning 6 to 15 days after her
arrival. He writes:
The initial effort in building consists of lashing the
supporting plants together and in this way form a cup-like
foundation upon which the remainder of the nest rests. Carex
and Calamagrostis are the chief materials used in this part
of the structure. The outer walls which are composed for the most
part of long strips of cattail leaves and stems and leaves of
sedges and grasses is the roughest part of the structure.
Water-soaked materials, often more than a foot long, are used here
as they are more pliable and can more easily be woven together.
The first strands are woven around the long axis and others, as
the nest assumes shape, are put in at various angles. Some of
these strands are fastened to the supporting structure by actually
weaving these stems into the nest. some of the growing leaves are
also woven into the outer walls. If the support is a sedge or a
grass, leaves may form a good share of the periphery. An opening
is left on one side about two-thirds of the distance from the
bottom of the nest. At this stage a dummy would be complete. The
walls average at least a half inch in thickness and the external
measurements of the entire structure approximate seven and five
inches for the vertical and horizontal diameters, respectively.
Inner diameters average five and three inches.
The outer shell is a small part of the completed structure,
and only 2 days are required to build it. The remainder of the
work is done from the inside and one must take a nest to pieces to
get an idea of its arrangement. Grass and sedge leaves and small
stems are used to form the second layer. This gives the walls
firmness and tends to fill in the large air spaces which are
necessarily present among the coarse materials of the outer walls.
The next layer to be added seems to function as an
insulating region. Cattail down, feathers, small unidentified
rootlets, entire plants of Lemna, and decayed fragments of Typha
and Carex are the materials most often used. These are also
placed into the structure in a wet condition so that, when dry,
they form a compact and tight-fitting region which serves as a
non-conductor of heat, cold, and moisture.
The innermost region is composed of finely shredded pieces
of the vascular materials of the plants forming the outer layers.
A large proportion of it is very fine strips of sedges and grasses
of the preceding year. Feathers of almost any available sort are
used here. Those from the following birds have been identified:
Red-winged Blackbird, Virginia Rail, American Bittern, Pheasant,
Ruffed Grouse, and domestic chicken. The projection at the opening
is a part of this inner lining. This "door-step" or sill
is always present in the female nest but is lacking in the nests
of the male. It is possible, therefore, to determine the sex which
built a given nest by checking for the presence of this sill. This
projection forms the floor of the opening and extends farther into
the nest than any other part of the lining. . . .
One wonders what the function of this door-step might be.
Perhaps it serves as a protection to the eggs and young as the
nest, owing to the uneven growth of the supporting plants, often
assumes a distorted position which would allow the contents to
roll out were it not for this structure. In like manner when the
nests are placed in sedges or grasses winds alter the nests to
such an extent that the young or eggs would be endangered if no
sill were there to prevent the catastrophe.
Several observers have reported mud in the lining of the nests,
but Dr. Welter and others have failed to note it; perhaps some mud
may be brought in accidentally with material secured from the
muddy floor of the marsh; it seems doubtful if the wrens ever
carry in mud intentionally.
The long-billed marsh wrens are notorious for building extra or
dummy nests, which are almost never occupied as brood nests. These
are built by the males, mainly during the 10 days or so
intervening between the arrival of the males and the coming of the
females. Anywhere from 1 to 10, usually not more than half a
dozen, are more or less incompletely constructed by a single male
within the limits of his territory. We do not fully understand the
reason for these extra nests; several theories have been advanced
to account for the habit, which is not wholly confined to this
species, but none of the theories appears wholly satisfactory. The
most plausible theory seems to be that it gives the birds an
outlet for surplus energy during the period of sexual activity,
for it almost always ends soon after the females arrive and mating
takes place. These male nests are never as fully completed as are
the brood nests; they usually do not go beyond the first stage
mentioned above, and are often abandoned before they reach even
that stage of completion. There is little evidence that they are
ever used as brood nests, or as sleeping places for the males, or
as territorial land marks.
A. D. DuBois mentions in his notes a nest that was of the
"usual construction except that the top of the nest was
covered by green leaves bent over and woven together over the top.
All the previous nests observed here, having the green leaves
woven over (nearly a dozen so noted) were empty nests."
Milton B. Trautman (1940) noted that, out of 208 nests,
observed at Buckeye Lake, Ohio, 161 had their openings facing
toward the south or west. There was one colony, "which was an
exception, for 11 of 19 nests opened toward the northeast."
Eggs.--The marsh wren's set may
consist of 3 to 10 eggs; the larger numbers are rare; 5 or 6 seem
to be the commonest numbers. They are generally ovate, sometimes
more rounded and rarely more pointed; they are not glossy unless
heavily incubated. Marsh wrens' eggs are unique in color, the
general effect being dull brownish, "Verona brown," to
"snuff brown," or the color of dry, powdered baking
chocolate. The ground color varies from "snuff brown" to
pale "pinkish cinnamon"; it is generally evenly
sprinkled with minute dots, or very small spots of darker shades
of brown, often partially, or wholly, obscuring the ground color;
these markings are sometimes concentrated into a ring or cap at
the large end. F. W. Braund tells me that "light or stony
gray" eggs are often found in Ohio. I have seen eggs with a
pinkish ground color and reddish brown spots that resembled the
eggs of the house wren, but these are rare. Very rarely an egg, or
a whole set of eggs, is pure white and unmarked.
The measurements of 40 eggs average 16.5 by 12.4 millimeters;
the eggs showing the four extremes measure 17.8 by 12.1,
17.6 by 13.3, 15.0 by 13.0, and 17.6 by 11.2
millimeters.
Young.--The incubation
period, as noted by several observers is about 13 days, and the
young remain in the nest for about the same length of times, or a
day longer, if not disturbed; Dr. Welter (1935) says 14 days.
Incubation seems to be performed wholly by the female, and she
feeds the young while they are in the nest; the male assists in
this afterward. Following are some of Dr. Welter's observations on
the young:
The type of food delivered to the young by the female is
determined to a certain extent by the age of the nestlings. At
first this consists of very small juicy morsels such as mosquitoes
and their larvae, larval Tipulids, midges, and other delicate
forms. The mother brings a whole beakful of food to the nest at
one time and parcels it out to the hungry occupants. . . . During
the morning and evening approximately 10 trips are made per hour
with food, but during midday this number is somewhat reduced.
As the nestlings grow the insects brought to the nest become
appreciably larger in size. Ground, diving, and long-horned
beetles, caterpillars of various assortments, sawflies and other
hymenoptera, and other accessible forms now constitute the diet of
the ever-hungry young. Sometimes the insect is so large that the
young bird experiences difficulties in swallowing it. In such
instances the female takes the hexapod to the side of the nest,
chops and tears it into several smaller morsels, and then brings
it back for a second trial which is usually a success. . . .
Even when the nestlings are very young, little time during
the day is given to brooding. Usually after a feeding or two the
young are brooded for a few minutes and then feeding is resumed.
My records show a total brooding of 18 minutes per hour when the
young are 2 days old. As the nestlings increase in size the
brooding periods become shorter and the intervals between such
periods become longer, so that, after the first week, they are
discontinued during the hours of daylight. . . .
The excreta, enclosed in their envelopes, are removed by the
female after feeding. These droppings are usually carried some
distance from the nest and deposited, but occasionally the female
has been observed eating them. . . .
When the young are small the fecal material is deposited in
the bottom of the nest. As the nestlings increase in size,
however, they maneuver about until they assume a position facing
away from the entrance, and the dropping is ejected on the
periphery of the nest. During the later period of nest life the
young succeed in ejecting the excrement with such force that it is
carried over the side of the nest and drops to the ground. . . .
Other waste materials, such as eggshell, infertile eggs, or any
young that might die in the nest are carried away. The young
increase in weight very rapidly, from about 0.87 gram at hatching
to about 11.08 grams at the end of the twelfth day. Meantime the
nest has become enlarged and worn as the young increase in size.
The young may leave the nest on the twelfth day, if disturbed, but
normally not until the fourteenth day. Occasionally one will
return to the nest for shelter, but they usually spend the nights
perched in the dense flags. The parents care for them for at least
2 weeks, though after the first 10 days they are able to secure
some of their own food. The family group remains together through
the summer and wanders about at some distance from the nesting
place.
It seems to be the consensus that two broods are raised in a
season, but not a third. Dr. Welter (1935) found no evidence of a
third brood. "The female begins her second nest abut 2 weeks
after the young of the first have left the nest. The majority of
the nests, then, in the regions studied would be started between
July 15 and August 1, with the last week in July the most active
period." Probably while the female is building the second
nest the male is busy with the first brood and is not very active
in building dummy nests.
Plumages.--Dr. Welter (1936) has
published another excellent paper on the development of the
plumage in the young marsh wren and on subsequent molts, to which
the reader is referred for details; it is fully illustrated with
drawings and photographic halftones. It is evident from the
photographs that the young bird is practically fully feathered in
the juvenal plumage before it leaves the nest, though the wings
are not fully developed and the tail is still rudimentary. Dr.
Dwight (1900) says that the natal down is white. In the juvenal
plumage the young wren is much like the adult, but the crown is
uniformly dull black, without the dividing brown area; the white
streaks on the back are very faint or lacking; and the white
superciliary stripe is indistinct. Dr. Dwight says that the first
winter plumage is "acquired by a partial postjuvenal molt
beginning about the middle of August which involves the body
plumage, the wing coverts, probably the tertiaries, but not the
rest of the wings nor the tail," young and old becoming
practically indistinguishable. Dr. Welter (1936) differs from Dr.
Dwight, as to the extent of this molt, saying: "Juvenals
collected during the fall of 1931 which are now in the Cornell
Collection show a molt of both rectrices and remiges." These
two authorities also differ as to the prenuptial molt. Dr. Dwight
says that the nuptial plumage, in both adults and young birds,
"is acquired by a complete prenuptial moult as indicated by
the relatively unworn condition of the feathers when the birds
arrive in May." He had no positive evidence of the molt,
however. Dr. Welter could "find no evidence of a prenuptial
molt in the series of specimens examined." The plumage of
birds living in such dense vegetation must be subjected to rather
severe abrasion, which might require a renewal of plumage
oftener than once a year; and it may be that the prenuptial molt
takes place during the late winter or very early spring, before
the birds arrive on their breeding grounds. Dr. Witmer Stone
(1896) agrees with Dr. Dwight's view, and I have seen some half a
dozen specimens, taken in North and South Carolina, Florida, New
Mexico, and Mexico, between February 23 and March 28, that show
various stages of a complete prenuptial molt. Whether these are
adults or young birds I do not know.
Food.--The marsh wren feeds almost
entirely on insects and their larvae, which it obtains on the
marsh vegetation or on the floor of the marsh. Dr. Welter (1935)
says that "much of the food is obtained near or from the
surface of the water. . . . It is not unusual to observe the bird
as he sights a juicy morsel fly into the air and capture it in the
manner of a flycatcher. Insects as large as dragonflies are taken
in this way. . . . Coleoptera and Diptera assume the highest rank
while various other orders are represented to a lesser degree.
Carabidae and Dytiscidae occur more frequently among the beetles
than any other forms while a large percentage of the Diptera
belong to the Tipulidae."
F. H. King (1883) reports from Wisconsin that "of 14
stomachs examined one ate 1 ant; one, a caterpillar; one, 3
beetles; three, 3 moths; one a small grasshopper, one, 5
grasshopper eggs; one 1 dragonfly; and one a small snail."
Mosquito larvae are probably prominent in the food, as are larvae
of other flying insects, diminutive mollusks, and aquatic insects.
Forbush (1929), referring to Massachusetts, says that "in the
salt marsh at high tide, it feeds on insects which crawl up on the
grass and reeds, and at low tide it feeds largely on minute marine
animals which it finds on or near the ground."
Behavior.--The marsh wren is much
more often heard than seen. As we drift along some quiet stream
bordered by extensive cattail marshes, we hear all about us the
gurgling, bubbling songs, or the chattering, scolding notes of the
birds, but not one is in sight in the dense jungle of flags.
Perhaps one may explode into the air, rising a few feet above the
cattails with an outburst of enthusiastic song and drift down
again into cover; or we may see one make a longer flight from one
part of the marsh to another, buzzing along on slow, direct,
steady flight with rapid wing beats. If we watch quietly,
curiosity may prompt one to come peering at us with furtive
glances from the shelter of his retreat, clinging with feet wide
apart to two swaying stems like a little acrobat doing the
"splits"; his tail is held erect or pointed saucily
forward and his head is lifted so high that head, body, and tail
seem to form a feathered circle. He climbs nimbly up and down the
reeds like a feathered gymnast, now gliding down to the base to
pick some food from the water, now gleaning along the stems, and
again swinging jauntily from a swaying top. He is the embodiment
of active energy, always in motion, never still for a moment,
always chattering, scolding, or singing. He is a shy and elusive
little mite; if we make the slightest motion while watching his
antics, he vanishes instantly into the depths of his reedy jungle.
Although most of the marsh wrens probably live in harmony with
their neighbors in the marsh, some, perhaps many, have formed the
bad habit of sucking the eggs of least bitterns and red-winged
blackbirds, as reported by several observers. For example, Dr.
Chapman (1900) saw one of these wrens puncture all the eggs in two
nests of least bitterns, and he attempted to photograph the bird
in the act; the wren did not eat the contents of the eggs, though
it may have returned to do so later; it looked like a case of pure
viciousness. And Dr. A. A. Allen (1914) says that "of 51
nests of the Redwing observed in a limited area, the eggs of 14
were destroyed" by marsh wrens, "and it is not at all
uncommon to find one or more of the eggs of a nest with neat,
circular holes in one side, such as would be made by the small,
sharp beak of a wren." One that he watched "began to
drink the contents much as a bird drinks water. After a few sips,
it grasped the eggshell in its beak and flew off into the marsh,
where it continued its feast." Dr. Welter (1935) evidently
thinks that such behavior is exceptional for he says: "Many
nests of other species of birds were under observation in the
marsh and at no time were punctured eggs found or other
indications of egg eating by the Marsh Wren observed."
Voice.--Wilson (Wilson and
Bonaparte, 1832) evidently did not admire the vocal powers of the
marsh wren, saying that "it would be mere burlesque to call
them by the name of song," for "you hear a low,
crackling sound, something similar to that produced by air bubbles
forcing their way through mud or boggy ground when trod
upon"; this is a fair description of some of the notes, but
he apparently was not referring to the full song, parts of which
are quite musical. F. Schuyler Mathews (1921) says that the song
"ripples and bubbles along in a fashion similar to that of
the Winter or House Wren, but with a glassy tinkle in tone not
characteristic of the songs of the other species and a tempo
perceptibly more rapid than that of the House Wren's music."
Dr. Charles W. Townsend (1905) writes: "The song begins with
a scrape like the tuning of a violin followed by a trill with
bubbles, gurgles, and rattles, depending no doubt on the skill or
mood of the performer, at times liquid and musical, at other times
rattling and harsh, but always vigorous. It ends abruptly but is
generally followed by a short musical whistle or trill, as if the
Wren were drawing in its breath after its efforts. I have heard
one sing fifteen times in a minute."
Dr. Welter's (1935) description is only slightly different; he
dissects the song into three parts; first a grinding sound
consisting of two to five notes with somewhat the quality of the aac
notes of the white-breasted nuthatch; then comes the more musical
"warble-like" part, which reminds him "of a sewing
machine of the older sort being run rapidly, but of course it is
less metallic and more musical. It has much of the spontaneity of
the House Wren's song but is otherwise quite distinct. This middle
section begins at a low pitch, climbs upward, and then descends
again." The third section he calls a trill which is again
"quite low but lacks the harshness of the beginning of the
song. . . .
"This entire song is given during May and most of June.
Toward the end of the month, however, the last part is often
omitted and often neither the beginning nor the end is
heard." The song period seems to cease entirely in August,
but the full song has been heard in October, which may mean that a
second song period occurs in fall.
The marsh wren is a persistent singer, chiefly during the early
morning and the evening hours, but during the height of the season
it sings all day and often at night. Only the male sings. He sings
while clinging to the reeds or while moving among them; he
indulges in his most delightful flight song while flying above the
vegetation from one part of his territory to the other; or, rising
in the air to a height of several feet, he flutters down to cover
again in full song.
This wren also has several alarm, call, or chattering notes.
According to Dr. Welter (1935)--
the "kek kek" or "tshuk" is given by the
female. The male's note sometimes resembles this also but can
usually be distinguished by its more grating nature and may be
described as "rrek." A series of notes is usually given
together so the "rrek's" do not sound very distinct as
they roll into each other producing a chattering. The "kek"
notes, however, while also given together, maintain their
identity. The female has a hissing sound that she gives if too
closely pressed by the male. Preceding copulation the female has
been heard to give a trill like that at the end of the male's
song.
The call notes of the young are quite similar to those of
the adult. The nestling, when the female arrives with food, gives
a beady "peep" or "peet." At first these notes
are scarcely audible but as the young become older and stronger
the "peet" is clearly heard. As the young leave the nest
the "peet" gradually develops into a "queck."
It is much more squeaky than the adult "kek" and also
lacks the woody quality. The notes of the juvenal become more and
more like those of the adult until they are indistinguishable.
He says that the songs of the young males begin late in August
and are entirely different from those of the adult. They reminded
him at first of "the efforts of a not altogether successful
Catbird," but they were "given in a more rasping manner.
The grating notes of the beginning and the trill at the end are
usually omitted by young birds."
Mr. Trautman (1940) "timed an isolated singing male whose
territory was in a small stand of cattail and found that between
10 p.m. and 3 a.m. his average was 9 songs a minute."
Another, in a similar situation, sang at the rate of 11 songs a
minute between 1:40 a.m. and 2:50 a.m. on a moonlight night. The
singing slowed down during the middle of the day, between 10 a.m.
and 2 p.m., to 4 songs a minute. "The amount of singing done
by these birds declined sharply after mid-August, and by September
5, only an occasional, half-hearted song could be heard."
Aretas A. Saunders writes to me: "The song of this bird is
rather low-pitched and guttural, or sometimes squeaky. It consists
of a series of rapid notes, so rapid as to call the result a
trill, but more frequently slow enough to count the number. In 26
of my records, without trills, the number of notes varies from 8
to 16 and the average number is 12. In a majority of the songs the
notes are all equal in time, but some have portions where the
notes are more rapid in part of the song. These portions are
sometimes the beginning and sometimes the end, or occasionally the
middle of the song.
"The pitch of the notes varies from C'' to C'''. One
record is all on one pitch (B'''). A number of others are all on
one pitch except the first or the final note, but others vary in
numerous ways. The greatest variation in pitch in any one song is
2 1/2 tones, and the average 1 1/2 tones. I have occasionally seen
a bird sing a flight song, when the song is somewhat more
prolonged than I have described, but I have never succeeded in
getting a record of this song.
"In spite of the simplicity of this song the individuals
vary it considerably. I have recorded five different songs from
one individual. The quality sometimes changes from guttural to
squeaky in the same song. The time of songs varies from 1 1/5 to 2
seconds, though flight songs are probably longer."
Field marks.--One hardly needs
field marks to recognize a long-billed marsh wren, for it is wren
like in appearance and behavior, and no other wren lives in such
wet marshes. If perchance it is seen in the drier part of a marsh
or meadow, it can be distinguished from the short-billed marsh
wren by the blackish, unstreaked crown, the white line over the
eye, and the black upper back streaked with white.
Enemies.--Hawks and owls would
have difficulty in capturing these active little birds as they
dive into their dense retreats. Red-winged blackbirds are often
seen chasing wrens for reasons stated above. Dr. Welter (1935)
mentioned three small mammals, meadow mice, jumping mice, and
Bonaparte's weasels, as probably guilty of destroying some eggs
and young. He says that Dr. A. A. Allen has seen bronzed grackles
eating the young and has found bumble bees occupying the nests.
Fleas, lice, and hippoboscid flies sometimes damage the young.
Fall.--Dr. Welter writes: "There
is no marked exodus of birds from the marsh at a given time in the
fall. At first the young of the year remain in family groups but,
as the time of departure approaches, there is an apparent flocking
together of young birds, usually near the water's edge. At
this time 25 or 30 birds may be observed together feeding near the
surface of the water. . . . The first birds to leave are the
adults and some of the young of the first brood." No adults
were found after September 10; the birds that remain after that
date are young birds, mostly those of the second brood, either in
juvenal plumage or molting out of it. "As these birds
complete the molt they, too, depart for their winter homes so
that, by October 20, only a few scattered individuals remain. By
the first of November these, also, have departed."
Elon H. Eaton (1914) describes the departure thus:
On one occasion while I was concealed in a blind watching
for ducks to enter the marsh, I saw the last representative of
this species leave the marshes at the foot of Canandaigua Lake. It
was a cool night late in October when the moon was at the full.
The little fellow uttered a feeble warble which attracted my
attention and then rose from near my station, fluttering higher
and higher into the air until lost at an elevation of about 300
feet, where I caught my last glimpse of him against the full moon.
The following morning when I visited the marsh no more wrens were
left. Evidently they migrate at night, and high in the air, so as
to see their way and escape their enemies more successfully.
Winter.--Most of the prairie marsh
wrens migrate in fall and spend the winter in Mexico or along the
Gulf coast to western Florida. But some few individuals remain in
their summer haunts all winter in the shelter of the dense cattail
marshes. There are winter records for Massachusetts, Connecticut,
New York, and Ohio. It may be that they are more common in winter
than we realize, for they are silent and remain well hidden in the
marshes where they are hard to find.
Marsh Wren*
Cistothorus palustris [Prairie
Marsh Wren]
*Original Source: Bent,
Arthur Cleveland. 1948. Smithsonian Institution United
States National Museum Bulletin 195: 248-259. United States
Government Printing Office
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