Feeding

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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: "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 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 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.

coleopteran orthopteran
unspecified 187 unspecified 120
carabid 39 locustid
cicindelid unspecified 34
unspecified 18 Arphia crassa 1
Cicindelasp. 2 Melanopluscf.differentialis, 2
hydrophilid Schistocercacf.lineata 1
unspecified 18 Xanthippuscorallipes 2
Hydrous sp. 1 tettigoniid
scarabaeid unspecified 3
unspecified 1 Daihiniasp. 1
Canthonsp. 3 homopteran
silphid cicadid
Necrophorussp. 1 unspecified 15
Tibicencf.pruinosa 1
lepidopteran(unspecifiedmoth), 3

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.

                                                                                                                                                                                                                                                                                                           

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