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Observations of the I first became enamored with the American Swallow-tailed Kite during a trip to Everglades National Park in April of 2004. While stopping at the visitor’s center at Flamingo, I saw my first Kite performing aerial acrobatics above the trees across the parking lot. I had never before seen such grace and beauty in the flight of a bird. I spend the next couple of years learning everything I could about this bird and how to best photograph it. The American Swallow-tailed Kite is a raptor belonging to the elanid family of Kites. It measures 19 to 26 inches (48 to 66 cm) with a wingspan of around 48 inches (122 cm) and weighs about 1 pound (17 oz). Its colors are a contrasting deep black and bright white, with some of the black feathers showing some iridescence. The flight feathers and tail are all black with most of the rest of the bird being white. It has a large forked tail giving it its name. The scientific name, Elanoides forficatus, is a Latin-Greek hybridization of elanus (meaning kite) and eidos (meaning “to resemble”) and forfex (meaning scissors). Other common names previously used include Fork-tailed Kite, Swallow-tailed Hawk, and Scissor-tailed Kite. The current accepted common name American Swallow-tailed Kite is meant to distinguish it from its smaller cousin the African Swallow-tailed Kite (or Scissor-tailed Kite), Chelictinia riocourii.
The Swallow-tailed Kite once ranged as far north as Minnesota and Oklahoma, but due mainly to habitat loss because of changes in land use, its range is now primarily restricted to the southeastern United States and parts of Texas. They are also found throughout Central America and tropical South America. Their breeding range is from the southeastern United States to eastern Peru and northern Argentina. The U.S. and Central American populations winter in South America, where they are resident year round. In South Carolina the species is considered endangered, and it is listed as threatened by the state of Texas. It is considered rare in the state Georgia, but for much of its current range the population is considered stable and it is listed as a species of least concern. I was first able to observe Swallow-tailed Kites closely when a colony of them nested near Doctors Hospital and the University of Miami in Coral Gables, Florida during March of 2006. Swallow-tailed Kites build their nests on the tops of tall trees, usually bordering a water source. The preferred tree is the Slash Pine (Pinus elliottii). In southeastern Florida this has been replaced by the Australian Pine (Casuarina equisetifolia) usually bordering a canal or lake. Australian pine is not a true pine tree and was introduced to Florida in the late 1800’s to prevent soil erosion along ditches, canals, and beaches. Their proximity to canals and their height, growing up to 90 feet, have made them irresistible to the Swallow-tailed Kite as a favored nesting location. Nests built on Australian Pine fail more often than those built on traditional Slash Pine, due to the weaker and brittle nature of the tips of Australian Pine branches. Strong winds from thunderstorms and hurricanes readily damage nests built on Australian Pine. Indeed that appears to be the case with the colony that nested in Coral Gables. A series of early summer thunderstorms bringing 60 mile per hour winds and golf ball sized hail caused the colony to abandon their nests.
Swallow-tailed Kites will return to and even refurbish old nests, but they often abandon them early on in favor of building a new nest, sometimes nearby the old one. Both the male and female gather material to build the nest. Small sticks and Spanish Moss (Tillandsia usneoides) are gathered in flight by swooping down on trees. In southeastern Florida, most of the material is gathered from nearby oak trees (Quercus). The material is carried in the feet and is transferred to the bill before landing. During the nest building phase courtship continues with the male bringing food back to the female while she is perched near the nest. Pairs will copulate throughout the nest building phase, until eggs are laid and incubation begins. Both the male and the female take turns incubating the eggs, but the female usually takes the bulk of the work. One bird will usually return to the nest with additional nesting material to relieve the other. One to three eggs are laid and incubation takes 28 to 31 days. There is only one clutch per year, even when nest failure occurs early in the breeding season. In 2008, the same colony of Kites was nesting on Australian Pines at the Riviera Country Club in Coral Gables, Florida. The location was on private property and I was not able to get permission to observe them. However, in 2009 a pair of Swallow-tailed Kites nested in an Australian Pine near Davie, Florida. Again the location was on private property, but by asking permission from the land owner the Everglades Photographic Society was able to secure permission to observe and photograph the nest.
The Kites were first observed gathering twigs and Spanish Moss from oak trees in the nearby parking lot in mid-April. Nest building had already begun, and by April 22, eggs had been laid. The female began spending most of her time in the nest, and was only relieved by the male for short periods of time. Swallow-tailed Kites sometimes lay two eggs and raise one young. The first chick to hatch will kill the younger chick, usually within the first two weeks. This is known as obligate siblicide, and this has been observed in Florida more frequently than in other areas.
On May 23, I first observed the male returning to the nest to seemingly regurgitate food, but the chick was still not visible. During the first week the chick was not visible in the nest and the parents would return to feed it through regurgitation. As time went by the chick became more and more visible and soon the male was bringing back recognizable prey items. The male does most of the hunting, returning to the nest with food for both the female and the chick. When the female leaves the nest to hunt it is usually just for her, rarely returning with anything for the chick to eat.
Their diet consists mainly of large insect, small birds, small mammals, reptiles, and amphibians usually taken from tree tops. The Kites in southeastern Florida seem to feed mainly on bird nestlings, often raiding the nests of American Crow (Corvus brachyrhynchos), Northern Mockingbird (Mimus polyglottos), Red-winged Blackbird (Agelaius phoeniceus), Mourning Dove (Zenaida macroura), and White-winged Dove (Zenaida asiatica). The two types of prey most often brought back to this nest site were iguana hatchlings and Rock Dove nestlings. The Green Iguana (Iguana iguana) is now firmly established in Florida, after starting off as illegally released pets. The Rock Dove (Columba livia) is your typical feral pigeon that can be found in nearly all urban locations around the world. The Swallow-tailed Kites of southeastern Florida have adapted well to feeding on these non-native species.
Swallow-tailed Kite chicks will fledge in 5½ to 7 weeks after hatching. By June 1, the chick was now clearly visible in the nest when it raises its head to feed. The small bird is all covered with white down feathers. On June 11, the black primary feathers were now visible as pin feathers growing on the wing. Images taken on June 20 showed that much of the down feathers have now been replaced by adult feathers. The top sides of the wings were now black, very similar to the adults. Most of the primary feathers and the tail have grown in, but the secondary flight feathers still needed to grow.
On June 21 the adults began copulating again. There isn’t enough time to raise a second clutch before migration begins, so these copulations must be some way of reaffirming the bond between the adult birds. The copulations usually occur in the morning and are often repeated several times over the course of several hours. The ritual is initiated by the female as she leans forward and vocalizes to the male.
By June 27 the chick will occasionally stand at the side of the nest and practice flapping its wings. It still lacks some coordination, but that is changing rapidly. The adult Kites will try to entice the young Kite to the edge by not immediately delivering food to the nest. Instead they circle the nest with the prey in their beaks, causing the young Kite to become excited and move toward the edge of the nest. On June 30 under wet and windy conditions the Swallow-tailed Kite chick stepped out of the nest onto an adjoining branch; his first of many forays out of the nest. During his time out of the nest he’ll face the wind and practice flapping his wings. After four days of small forays onto branches beside the nest, the fledgling Kite, without hesitation, took a leap of faith out of the nest on July 4th. During his brief first flight, he circled the Australian Pine that has served as a home these past few months. Landing safely on one of the branches, he’ll repeat these short flights a couple of times a day for several days to build his flight confidence. His landing needs some work too. During one of these flights the young Kite landed on a branch that could not support his weight, and he ended up hanging upside down for several minutes, before flying off to a more secure limb.
With each passing day the young Kite’s flights become more numerous and go longer distances, but he still returns to the nest tree after each flight. On July 8th the juvenile began incorporating new flight maneuvers into his practice. The first involves folding one wing during flight allowing him to dive and turn quickly, a maneuver adult Swallow-tailed Kites use to catch insects in flight. The second involves skimming the tree tops with his feet; which again adult Kites do to capture prey. On the same day he also landed on an oak tree, the first time he’s ever made a landing outside of the Australian Pine with the nest. The adult male continues to bring back food for the juvenile Kite, but the feedings have become less frequent and start later and later in the day. When the chick was newly hatched feedings began as early as 7:00 AM (EDT), but now feedings don’t start until almost 9:00 AM (EDT).
It is late afternoon on July 11, and the juvenile Kite is now observed riding high into the thermals for the first time. This is the flight skill he will rely on to make the long migration to their wintering grounds. By using the rising warm air to gain altitude, Swallow-tailed Kites can make long journeys without having to expend much energy flapping their wings. After July 13th the Swallow-tailed Kites along with the fledgling stopped making regular appearances at the nest site. They would return from time to time and could be seen flying around the area, but we could no longer count on the predictability that made observations easy. On July 18th the Kites were seen preening at the nest site along with a fourth Swallow-tailed Kite. After a chick has fully fledged, Swallow-tailed Kites lose their territoriality and begin congregating with others of their species. The fledgling Kite soon departed with both parents. The adult Kites will always be nearby and will continue to feed him, but he’ll also learn to hunt for his own food; by plucking dragonflies hovering in the air. He’ll need all of these skills; because in late July and early August they will join up with many families of Swallow-tailed Kites at one of the traditional roosting locations in Florida. They will gather there just before they begin the migration across the Gulf of Mexico, over to Central America, and ultimately onto their wintering grounds in South America.
Photographing the American Swallow-tailed Kite presents a unique set of challenges. The first of which is that this bird is the most acrobatic flier of all the raptors, requiring good flight tracking technique. Second, the deep contrast between the bright white and dark black often presents an exposure problem. Overexpose the image and too much detail is lost in the white areas, while underexposure causes a loss of detail in the black feathers. I’ve found that metering off the blue sky and then adjusting the camera’s setting for around +2/3 exposure works best. Keep in mind that you need to have a high shutter speed and enough depth of field to properly capture a bird in flight. The use of fill flash with a flash extender can also help open up the details in the darker under parts of this bird. The Swallow-tailed Kite is a favorite among birders and photographers. Its dramatic silhouette and aerial ballet make it a joy to watch. It is truly the most graceful of birds to behold in the sky. |
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