[Pg 503]

University of Kansas Publications

Museum of Natural History

---

Volume 12, No. 11, pp. 503-519



  October 25, 1963  

Observations on the Mississippi Kite

in Southwestern Kansas

BY

HENRY S. FITCH

 

 

 

University of Kansas

Lawrence

1963

[Pg 504]

University of Kansas Publications, Museum of Natural History



Editors: E. Raymond Hall, Chairman, Henry S. Fitch,

Theodore H. Eaton, Jr.



Volume 12, No. 11, pp. 503-519

Published October 25, 1963



University of Kansas

Lawrence, Kansas



PRINTED BY

JEAN M. NEIBARGER, STATE PRINTER

TOPEKA. KANSAS

1963









29-7863

[Pg 505]

The Mississippi kite (Ictinia mississippiensis) is one of the common
raptors of Kansas, occurring regularly and abundantly in summer
in that part of the state south of the Arkansas River. In 1961, in an
attempt to find out more about the ecology of the species in Kansas,
I made several trips to parts of the state where kites could be found
in numbers, notably to Meade County State Park in the southwestern
part of the state, 7½ miles south and five miles west of
Meade. Little has been written regarding the species in this extreme
northwestern part of its breeding range, where it thrives
under ecological conditions much different from those that prevail
elsewhere in its range. Also, the social behavior and food habits
have been given relatively little attention.

In my field study I was helped by my son, John H. Fitch, who
climbed to many kite nests and spent many hours observing in the
field. My daughter, Alice V. Fitch, likewise aided me by keeping
nests under surveillance. Dr. Claude W. Hibbard of the University
of Michigan and Mr. Harry Smith, superintendent of Meade State
Park, also kindly provided much useful information concerning
the history of the colony of Mississippi kites at the Park. Mr.
William N. Berg analyzed pellets, and Dr. George W. Byers kindly
checked many of the identifications, and provided generic and
specific determinations for some of the insects.

In general, the range, habits and ecology of the Mississippi kite
are already well known through the publications of Audubon
(1840), Chapman (1891), Bendire (1892), Ganier (1902), Wayne
(1910), Nice (1931), Bent (1936), Sutton (1939) and Eisenmann
(1963). The breeding range is the southeastern United States,
chiefly within the Austroriparian Life-zone, but extending northwest
through much of Oklahoma and into southern Kansas. The
species is highly migratory. Wintering Mississippi kites are known
from Argentina and Paraguay (Eisenmann, op. cit.:74), and most of
the population probably winters in southern South America, but
records outside the breeding range are few.

The Mississippi kite is perhaps one of the most social raptors. It
is highly gregarious, not only in its migrations but in breeding
[Pg 506]
colonies. All breeding pairs seen were closely associated with other
individuals, with no territorial hostility; signs of intraspecific intolerance
are rare, even where the kites are abundant. In the nesting
season many of both sexes perch together in the same tree, and
groups tend to keep together as they forage.

Secondary sexual differences are slight. Seven males in the University
of Kansas Museum of Natural History collection average
351 (342 to 360) millimeters in length, and six females average 361
(348 to 370) millimeters. Sutton (op. cit.:44) collected 16 breeding
kites near Arnett, Oklahoma in 1936 and 1937 and recorded that
eleven males averaged 245 (216 to 269) grams and five females
averaged 311 (278 to 339) grams. As indicated by Sutton, the
head is paler in the adult male than in the female, and at close range
this difference will serve for identification of the sexes. The difference
in size is scarcely noticeable in the field.

Habitat

In Kansas this kite seems to prefer open and even barren terrain,
in contrast with its habitat in forests of the southeastern states.
Typical habitat of Kansas is that of the High Plains, dominated by
a short-grass climax of blue grama (Bouteloua gracilis) and buffalo
grass (Buchloë dactyloides), with sagebrush (Artemisia sp.),
prickly pear (Opuntia sp.) and other somewhat xerophytic vegetation.
In the Gypsum Hills of south-central Kansas near the
Oklahoma border, the Mississippi kite finds habitat conditions exceptionally
favorable. This is an area of broken topography, dissected
by small steep-sided ravines, often with brush and scrubby
trees on the slopes.

At Meade County State Park groves of cottonwoods (Populus deltoides)
provided abundant places for perching and nesting. At
this locality an artesian well provided an abundant year round
water supply, which was impounded into an artificial lake half a
mile long and a little less than a quarter mile wide. Water was
also impounded in a series of small ponds maintained for the benefit
of fish and waterfowl. Along with other improvements extensive
plantings of cottonwoods and other trees were made with relief
labor in the nineteen thirties. Trees were scarce on the area originally,
but by 1961 there were almost continuous groves in an area
nearly two miles long and three quarters of a mile wide encompassing
the lake and ponds and adjacent areas. In conversation
at the Park in August 1961, Dr. C. W. Hibbard told me of his
observations on the colony of kites since 1936 when his paleontological
[Pg 507]
field work in that area was begun. He indicated an area of
less than two acres west of the artesian well to which the colony
had been limited in its nesting in 1936, because at that time few
trees were available as nest sites. In subsequent years, as the trees
in the artificially established groves increased in size and height, and
other trees became established naturally where the impoundments
had created favorably moist conditions, the nesting colony expanded
in all directions, and the number of kites increased tremendously.
When my observations were made in 1961, the nesting
area was co-extensive with the cottonwood groves, and there were
literally thousands of trees within the area that provided adequate
sites for nests.

Numbers

The maximum number of kites seen flying at one time at the
Park was 44, on August 22, 1961. Probably almost all there were
adults, because fledglings, even though able to fly strongly by this
date, were still spending most of their time perched. The colony
of kites was usually scattered over at least two square miles, and
at most times some were perched, others were flying low and
solitarily, hence it is improbable that the total population or a high
percentage of it could be seen together at any one time or place.
More than 40 nests were located in 1961, and probably at least as
many more were overlooked. There must have been a breeding
population of at least 100 kites, and probably as many as 150 in the
Park in 1961. H. B. Tordoff recorded on the label of K. U. Mus.
Nat. Hist. no. 30514, taken on September 1, 1951, in Barber County,
Kansas, that it was one of at least 200 at a communal roost.

Feeding

The Park and its vicinity stood out as a veritable oasis in an
almost treeless region of open rolling topography, with a short-grass
type of vegetation dominating. The kites displayed versatility in
their choice of places to forage. Often they soared over the cotton-*wood
groves, the lake, or the ponds, but at other times they flew
far out over the plains, and seemed to prefer such open situations.
A small herd of buffalo was maintained at the Park, and their closely
grazed pastures of several hundred acres were favorite foraging
grounds for the kites. Often the kites and buffalo were seen in
close association, and at times the kites must have benefited from
the movements of the buffalo, serving to flush certain insects such
as grasshoppers. The latter were probably the chief food source
of the kites in the heavily grazed pastures. Bent (1936:67) stated:
[Pg 508]
"A flock of from 3 to 20 will sail about a person, a horseman or a
team, traveling through grassy flats or bushy places, and seize the
cicadas as they are scared up." Dr. Hibbard told me that on one
occasion when he had caught a number of cicadas, he fed them to
a pair of kites by tossing them into the air one by one, and each
was seized by a kite which was flying nearby waiting expectantly.

Mississippi kites are noted for their buoyant and seemingly almost
effortless flight, and their prey is caught while they are on
the wing. In extended flights the kites soar, drift and circle with
frequent easy flapping, at variable heights. Sometimes they are
several hundred feet above the ground. Doubtless the height is
influenced by the types of insects that are flying, and where they
can be found most readily. Even at close range the catching of
prey by a kite is likely to be overlooked by an observer. After
being snatched from the air, the prey is usually eaten while the kite
is still in flight, and the movements of the head in pecking at the
objects held in the talons are much more noticeable than the slight
veering from the course of flight that signals the actual capture.
Kites were often watched while they were hunting in the open
areas around the Park. On June 1, 1961, my son and I observed
16 perched together in a small tree. From time to time each kite
would leave the tree in a short flight low over the surface of a
nearby pool, where it would snatch up prey, probably a dragonfly
in many instances, and would return to a perch to feed. Most of
the time one or several kites were in flight while the majority were
perched. Similar observations were made on smaller groups
perched on fence posts along the edges of large pastures. Gregarious
tendencies were evident from the fact that two or more of
the kites perched fairly near together on separate but sometimes
adjacent fence posts. Each kite in turn would glide from its post,
skim low over the ground surface for a few seconds, seize its prey
with a sudden slight swerving, and return to the fence (usually to
a different post from the one it had left) to feed upon the insect
captured. Grasshoppers of many species were abundant in the
area. It seemed that grasshoppers were flushed from the ground
by the bird flying near them and were picked off before they were
well underway. In any case the prey was taken from the air rather
than from the ground in all observed instances. Ganier (1902:86)
mentioned seeing one of these kites alight on the ground in a
cotton field, where it stayed for more than a minute, but perching
on the ground is unusual.

Most often kites that were catching their prey by skimming close
[Pg 509]
to the ground did not return to a perch but ate while they were
flying. Associations of groups on posts at edges of fields, in trees
or in flight were ephemeral as each bird seemed driven by a restless
urge to be in motion. The kites generally gave the impression of
catching their prey effortlessly and casually in the course of their
flights. However, on July 20, 1961, one flying over a pond was
seen to swoop three times in rapid succession at a dragonfly without
catching it. The kite then flew higher, circled, and swooped three
times more at the dragonfly, catching it on the last attempt. Most
of the insects preyed upon are slower and less elusive than dragonflies,
which are largely immune to the attacks of flying predators
because of their great prowess in flight.

Only on rare occasions could the kind of prey captured be observed
in the field. Food habits were studied by collecting pellets
of the kites at the Park, and analyzing them. The pellets were
usually disgorged early in the morning while the kites were still
on their night roosts in large cottonwoods. Often several kites
roosted in the same tree. The pellets were of characteristic appearance,
elliptical, approximately 15 millimeters in diameter, 30 millimeters
long, pinkish or purplish, composed of insects' exoskeletons
compacted, and comminuted to about the consistency they would
have after passing through a meat grinder.

A total of 205 pellets was collected—37 on August 20, 1960;
56 on July 18, 1961; 60 on August 4 and 5, 1961, and 52 on August
21 to 23, 1961. A total of 453 separate items was tentatively identified.
Obviously the material was far from ideal for the identification
of prey, which had to be reconstructed from minute fragments.
The kites are dainty feeders and discard the larger and less digestible
parts such as wings, legs, and heads. Often it was uncertain
how many individuals or how many kinds of insects were represented
in a pellet. Probably most pellets contained many individuals
of the same species, but these were not separable. Hence,
only 2.2 items per pellet were found, whereas Sutton found an
average of 22.2 items in each of the 16 stomachs that he examined.

Best information concerning kinds of prey utilized was obtained
soon after the fledglings had left the nest; on various occasions
these still clumsy young dropped nearly intact insects that were
delivered to them by the adults. These insects, recovered from
beneath the perches, were the basis for all specific and generic
determinations; other material was determinable only to order or
to family.

One of the most significant outcomes of the examination of pellets
[Pg 510]
was the finding that vertebrates were scarcely, if at all, represented
in the food. Three pellets contained shreds that seemed to be
mammal hairs, but in the absence of other remains, the diagnosis
is somewhat doubtful. Many species of small mammals, birds,
reptiles and amphibians were common in the Park or its vicinity,
but insects made up nearly all the recorded prey. Audubon (1840:73)
mentioned lizards and small snakes in the food and gave a
dramatic but perhaps imaginative account of a kite swooping and
snatching a lizard (anole) from the topmost branch of a tree. Goss
(1891:251) stated: "I have seen them swoop down, and, with their
claws, snatch lizards from the ground, rocks and old logs, sometimes
stopping to eat them, but, as a rule, feeding on the wing." Bendire
(1892:179) stated that the food was mostly insects "probably
varied with a diet of small rodents, lizards and snakes." Wayne
(1910:71) stated that the food consisted almost entirely of insects
and lizards. Bent (1936:67-68), after stating that small snakes,
lizards and frogs were sometimes taken, cited a statement in the
notes of G. W. Stevens that the latter had found the remains of
toads, mice and young rabbits in nests with young. However,
Sutton (op. cit.:51) in a detailed analysis of the stomach contents
of 16 kites in Oklahoma, found only insects and remains of one
small fish among a total of 358 prey items. Predation on vertebrates
must be rare, and perhaps requires further verification in view of
the rather vague character of the records so far published.

The following list includes both the prey found beneath perches
of fledglings and that identified from pellets, the latter mostly from
adult kites.

[Pg 511]
At Meade State Park I gained the impression that much of the
foraging is carried on near the nest. The short time lapse between
successive feedings was one indication, and from time to time while
keeping nests under observation, I saw kites that were individually
recognizable as the owners coursing back and forth in the vicinity.
However, only a few individuals were recognizable. For several
minutes before and after delivering food, such an adult was often
seen soaring within 200 to 300 yards of the nest, or sometimes
much closer. A somewhat different impression was received on
August 23, 1961, at Natural Bridge, south of Sun City, Barber
County, Kansas, where I observed two pairs of kites feeding fledglings.
One fledgling was seen to be fed ten times in a 1½ hour
period. The transfer of food from the adult usually required less
than a minute. Then the adult would leave the tree, in a ravine,
and drift away. Circling and soaring, it seemed to be wandering
aimlessly, but within two or three minutes it was usually out of
sight over the horizon. In what appeared to be slow, lazy, flight
it usually drifted off to the west, to more upland areas of short grass
and sage brush. Once, watching from a high knoll I succeeded in
keeping it in view for almost five minutes, and during most of this
time it appeared to be between one and two miles away, but it
finally moved off even farther. Dr. Hibbard mentioned seeing
kites in the vicinity of the Jinglebob Ranch eight to ten miles from
the Park, and he believed that these individuals had come from
the Park since there was no suitable habitat in the intervening
areas. Actually, the distance could have been covered in a few
minutes' flying time, but it is unlikely that these individuals were
feeding young at the Park, else they would not have wandered so
far. On several occasions groups of from three to 20 individuals
were seen in open terrain as much as four or five miles from the
Park.

Breeding Cycle

Probably kites arriving from their northward migration are already
paired. In those observed at the Park in the first week of
June, there was no indication of courtship, or of sexual rivalry. On
June 1, 1961, incubation had begun. The birds had arrived some
three weeks earlier, according to Smith. Although arriving from
the south long after most raptors have begun their nesting, the
kites are not further delayed by establishment of territories and
choosing of mates, and nesting is underway soon after their arrival.
[Pg 512]
According to Sutton (1939:45) the nest-building is an exceedingly
leisurely process. In the first two weeks after their arrival he observed
that the kites only occasionally bring a twig to the nest,
usually repairing last year's structure rather than starting a new one.
Sutton recorded egg-laying on May 17 and 18 and hatching on
June 18 in northwestern Oklahoma, and the timing of these events
must be similar in Meade County, Kansas.

Shortly before sunset on June 1 a pair was observed at close
range from a parked automobile as the kites perched on roadside
fence posts about 50 feet apart at the Park boundary. At this
time the birds lacked their usual restlessness and were perching
quietly, neither preening nor attempting to find prey. With no
preliminaries the male flew to the female and lit on her back to
copulate. The female was receptive but did not crouch in a horizontal
position. The mounting lasted for approximately a minute.
During the first 30 seconds the male was fully occupied with balancing
and positioning himself, and copulation occurred only during
the latter half of the mounting. During this interval cloacal contact
was effected three times, but was only momentary each time. The
birds were silent. After the male left, the female continued to
perch until flushed by my movements.

Judging from the nests that were examined, the kites of the
Meade Park area are well synchronized in their nesting, as all
arrive at approximately the same time. Bent (1936:66) stated that
if a kite's nest is robbed, the birds will lay a second set, either in
the old nest or a new one, about two weeks later. All young seen
at Meade State Park seemed to represent an age range of considerably
less than two weeks, and, presumably, no renestings were
involved.

Nests were variable in size. Some were remarkably small in
relation to size of the kites, and would scarcely have been credited
to this species, had not the kites been seen sitting on them. Nests
were from 10 to 18 (average 14) inches long and from 10 to 14
(average 11.7) inches wide, in forks or crotches of branches. The
branches supporting the nests were from 1½ to 10 inches in diameter.
The nests were constructed of twigs of approximately pencil size.
Of 37 nests at the Park, 29 were in cottonwoods, six were in willows,
and two were in elms. The figures probably reflect the relative
numbers of each of these species of tree rather than any clear-cut
preference of the kites. By the time nesting has begun the trees
have leafed out, and the nests are well concealed.

[Pg 513]
At the time of my visit to the Park, July 18 to 22, nestlings were
well grown, and were beginning to feather out. On August 4 and
5 the young were well feathered, but flight feathers were not fully
grown and the young remained in the nest or perched on nearby
branches. On August 21 to 24 the young were fully fledged, and
were able to fly strongly but they still spent most of their time
perching and those of a brood tended to stay near together, usually
in the nest tree.

In a total of 26½ hours of observation, 148 feedings were observed—on
the average one per 10.7 minutes. The interval changed from
an average of 12.8 minutes for 62 feedings on July 19 to 21, to 8.5
minutes for 59 feedings on August 4, and to 10.8 minutes for 27
feedings on August 21. The longer interval on July 19 to 21 may
have resulted from the greater furtiveness of the adult kites at this
stage in their nesting cycle. Nests usually were watched through
field glasses at distances of 50 to 100 feet. Ordinarily kites are not
disturbed by the presence of a person at these distances, but when
delivering food to the nest they seemed somewhat distracted and
sometimes stopped only momentarily then left, still carrying the
food. Usually they swooped at the observer when leaving; rarely
they swooped at him as they approached the nest. All observations
were between 10 a.m. and 5 p.m., and there was no obvious trend
according to time. Earlier and later in the day the rate of delivery
is probably less. The kites are notably late risers, and their activity
increases gradually after sunrise; in late afternoon activity tapers
off again. In 89 feedings, the average visit to the nest lasted 51
seconds but this average included a few relatively long stops, up to
four minutes in length, and 60 per cent of the visits were for intervals
of 30 seconds or less.

Insects often protruded from the bills of the adult kites delivering
food, but most of the food was carried in the throat. Sometimes
the gorge was much distended, although nothing protruded from
the mouth. The adult upon alighting sometimes would pass food
to the nestling, and sometimes would disgorge a mass of food in
the nest in front of the nestling. When the young were small, the
adult after having disgorged a food mass, remained to pick up the
food, bit by bit, and place it in the mouth of the nestling. However,
after the young were partly feathered out the adult merely left the
food for them. The nestling sometimes would peck at the disgorged
material for several minutes after the adult left before all
of the food was eaten.

[Pg 514]
The small nestlings are generally silent, but when handled or
otherwise disturbed, they give soft lisping peeps. By early August,
when the young have ventured from the nest bowl to nearby
branches, they become vocal and their calls can be heard more
often than those of the adults. The call of the adult has been well
rendered by Sutton (1939:43) with the syllables "phee phew"—a
whistle in which the first syllable is short (lasting only about one-fourth
of a second) with a rising inflection, clipped off short, while
the second syllable has a downward inflection, and is drawn out to
two or three times the length of the first syllable. The call of the
fledgling is soft, with a lisping quality; that of the adult is much
like it but is sharper and more piercing. Fledglings call frequently
while waiting to be fed, but as an adult approaches with food, the
calls are given in rapid succession and slurred to a high thin
squablike squeaking or squealing.

When fledglings are able to fly and have left the nest, the adults
generally pass food to them directly, rather than dropping the
regurgitated mass, which might fall to the ground and be lost. On
August 22 a fledgling was seen following an adult in flight, and was
also seen to eat while it was flying. At this stage, when an adult
fed one young of a brood, the other would sometimes fly to the
spot in an attempt to share the meal. However, the transfer of
food was usually rapid and the adult would leave within a few
seconds. Young often were seen to fly out from the nest tree and
maneuver in the vicinity, flying in a roughly circular course perhaps
100 feet in diameter and then returning to the nest tree, thereby
familiarizing themselves with their surroundings.

According to the consensus of published accounts, there are
usually two eggs per clutch, occasionally one or three. However,
Ganier (1902:89), who studied the species in Mississippi, wrote:
"Of all the nests I have examined [number unspecified] only one
was found to contain more than a single egg." Nice (1931:69)
recorded 19 sets of two each and seven of one each in Oklahoma.
In the course of my observations, 12 clutches of two were recorded.
A group of four fledglings were observed concentrating their activities
at a nest more than 200 feet from any other known nests;
possibly all belonged to the same brood, but this was not definitely
determined.

Many of the nests that were in use in 1961 appeared to be relics
from earlier years, as the material was darkened and disintegrating,
but probably a new layer of sticks had been added on the top.
[Pg 515]
Bent (op. cit.:65) mentioned this kite's habit of frequently using
the same nest in successive years. On one occasion as I drove over
a little-used road in the Park and passed a cottonwood grove where
kites were nesting, one of the birds swooped down and struck the
top of the automobile. In a subsequent conversation, Harry Smith
asked me if this had happened, and said that this particular kite
had struck his truck frequently when he drove past its nest. This
had occurred at the same place in three successive years, and Smith
was convinced that the same kite had used the nest each year,
although the bird was not recognizable except by its unusually
aggressive behavior. On dozens of occasions in the course of my
observations kites swooped at me when I was near their nests,
but, except for this one individual, they always veered away at a
distance of several feet or several yards.

At the time of my visit to the Park in early June, kites were
relatively silent and secretive in their behavior. Approximately half
of those that were incubating flushed when a person walked near
the tree, but others continued to sit on their eggs until a person
had climbed to within a few feet of the nest. Upon being flushed,
such a kite, in 50 per cent of observed instances, swooped at least
once at the intruder, but some of the kites would soar overhead,
watching without making any active defense. At the time of my
next visit, July 18 to 21, when the kites were feeding well grown
nestlings, behavior at the nest was much different. As soon as a
nest was located the parents began scolding and swooping. At
the first nest observed, a group of eight kites had congregated
within two minutes to scold and harass the intruders. Even kites
whose nests were kept under observation frequently, never became
fully reconciled to the intrusion but there was much difference
between individuals in this respect. Some were reluctant to deliver
food and, having secured prey, would fly about in the vicinity
without coming to the nest.

Mortality Factors and Defense

Joint defense against a common enemy was noted on July 21,
1961, when 21 kites were seen swooping at a Swainson's hawk
perched near the top of a large cottonwood, where it was partly
protected by foliage and branches. When I flushed the hawk, it
was pursued and harassed by the kites, some of which followed
it for nearly a quarter mile although there were no nests of the
kites nearby. On August 4 a group of six kites was seen heckling
[Pg 516]
a fledgling Swainson's hawk, which crouched among thick foliage
in the top of a tall cottonwood, as the kites swooped at it, sometimes
brushing it with their wings when they swept past. Dr. Hibbard
mentioned an instance in which a horned owl was flushed, and was
chased and heckled by a red-tailed hawk and by a group of kites.
The latter seemed to regard the owl as the greater enemy, but
ordinarily any large raptor arouses their hostility.

Because of their exceptionally swift and skillful flight, the adult
kites have few natural enemies, but the eggs or nestlings are vulnerable
to such enemies as crows, jays, the larger hawks and owls,
and to certain mammalian predators, notably raccoons. Also, many
nests probably are destroyed by the sudden and violent summer
storms that are characteristic of the High Plains. Bendire (1892:178)
cited observations by Goss that in a hailstorm in Barber
County, Kansas, eggs were destroyed in many kites' nests and some
of the nests were almost completely demolished. Several nests
found by me to have incubating eggs in the first week of June were
abandoned or had disappeared completely by July 18, but the
cause was not evident. One nest that was under observation on
July 22 had nestlings approximately two-thirds grown on that date,
but on August 4 only a few sticks remained, and the carcass of a
fledgling dangled from a limb ten feet below the nest. Even at
the Park where firearms are prohibited, kites are sometimes shot
by ignorant or malicious persons. In general, Kansas ranchers
recognize the harmless and beneficial habits of kites, appreciate
their esthetic appeal and protect them, but many persons use them
as convenient targets, with utter disregard for the Federal laws
protecting them. Because of the strong popular prejudice against
raptorial birds in general, laws protecting them are usually not
enforced. Law enforcement officers do not take action even when
clear-cut violations come to their attention. Arrest and prosecution
for the killing of any kind of raptor is almost out of the question
in Kansas.

Ratio of Immatures to Adults

In the juvenal plumage flight feathers of the kites are brown,
barred with white, much different in appearance from the dark,
slaty plumage of adults. Bent (op. cit.:67) stated that these barred
flight feathers are retained through the second summer, and he
quoted Mr. G. W. Stevens as having found kites breeding in this
immature plumage. On June 2, 1961, I attempted to determine
the ratio of these yearling kites to others in the population at the
[Pg 517]
Park. Most of the kites seen were in flight too far away to discern
definitely whether or not they were juveniles, and records were
limited to those seen at relatively close range. In a total of 108
records only 11 pertained to these yearlings and the remaining 97
were identified as of adults. Beyond doubt in the course of my
counts some individuals were recorded repeatedly, therefore the
counts are not entirely acceptable. However, on each occasion that
kites were seen in numbers in early summer, the adults greatly outnumbered
the juveniles. The approximate nine to one ratio of
adults to yearlings seems much too high. Even if the difference
is much less than indicated, the high ratio of adults to yearlings
would seem to imply that the adults have a long life expectancy.
A rather improbable alternative is that some of the yearlings remain
in winter quarters or wander elsewhere rather than accompanying
the adults on the return migration to their breeding grounds. Still
another alternative is that the breeding season of 1960 was relatively
unsuccessful, but this idea is negated by my own observations at
the Park in late 1960, as recently fledged young were numerous then.

At the time of my visit to the Park August 21 to 24, 1961, all young
had recently left the nests and were able to fly. However, their
behavior was so much different from that of the adults that a
reliable ratio could not be obtained. The fledglings tended to remain
in the nest tree, or to make relatively short flights near it,
while the adults occupied with catching of prey for themselves and
their young, spent much of their time aloft. The adults were hence
far more conspicuous than the fledglings. However, it is my impression
that the fledglings were from one-third to one-fourth as
numerous as the adults. If this ratio is correct, and if all adults had
bred, from two-thirds to three-fourths of the eggs and/or nestlings
must have been destroyed. This rate of loss seems reasonable in
view of the known histories of nests observed in June and again
in July, and of the fates of birds' nests in general.

Summary

Mississippi kites were studied in southwestern Kansas in the
summer of 1961, at various localities, especially at Meade State
Park. At this locality, near the northwestern limit of the breeding
range, the kite thrives in typical High Plains habitat dominated by
a short-grass type of vegetation, but availability of trees suitable
for nests is a limiting factor. Since maturing of extensive groves
of cottonwoods and other trees planted at Meade State Park, the
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colony of kites has increased tremendously and the breeding population
probably exceeded 100 in 1961.

The kites are social in all their activities and do not maintain
territories. The sexes differ little in appearance, but males are
slightly smaller than females and have paler heads. Food consists
almost entirely of flying insects, and these are usually eaten while
the kite is in flight. Kites that are feeding nestlings may travel up
to two miles from the nest or perhaps considerably farther in the
course of their foraging. For 148 feedings of nestlings the observed
intervals averaged 10.7 minutes. Most published references to the
food habits mention predation on small vertebrates, especially
lizards, but including also snakes, toads, rodents, and even rabbits.
In my study a total of 205 pellets were collected and 453 insects
were tentatively identified but the total number of insects in the
pellets was much larger. No vertebrates were identified from this
sample and among 358 prey items identified from kite stomachs
collected in Oklahoma, by Sutton, vertebrae of a small fish were
the only vertebrate remains. Further verification of predation on
mammals, reptiles and amphibians by this species is needed. Of
the insects distinguished in pellets, beetles including carabids, cicindelids,
hydrophilids, scarabaeids, and silphids were most numerous
(270) and grasshoppers (164) were second; also there were
16 cicadas and three moths.

Kites arrive in Kansas about the second week in May. Often
old nests are repaired and used over again. Hatching is about
mid-June. Normally there are two eggs per clutch. By mid-August
the fledglings are learning to fly. By the latter part of August they
are learning to capture their insect prey, and in early September
southward movement of the entire population begins.

Eggs and/or young in many nests are destroyed by hail or high
wind in the sudden violent storms that are characteristic of the
High Plains. Mississippi kites are often shot by misguided persons,
and benefit little from the protection supposedly provided by Federal
law. However, the adults probably have few natural enemies.
The high ratio of older adults to yearlings indicates that the life
expectancy is long. Through their second summer the kites retain
their barred immature plumage, and can be readily distinguished
from adults. Only ten per cent of the kites recorded in 108 June
sight records at the Park were in juvenile plumage.

Literature Cited

Audubon, J. J.

Bendire, C. E.

Bent, A. C.

Chapman, F. M.

Eisenmann, E.

Ganier, A. F.

Goss, N. S.

Nice, M. M.

Sutton, G. M.

Wayne, A. T.

Transmitted June 3, 1963.

[The End]