Elanus leucurus

Geographic Range

The White-tailed Kite is native to North America along the pacific coast region as well as southern Texas and southern Florida. There has been rare sightings all throughout the southern states, in areas it has previously not inhabited. The white-tailed kite is also native to most of Mexico and Central America (Sibley, 2014). This raptor is non-migratory, but is known to wander widely which explains the random sightings throughout the southern United States. Breeding ranges include south eastern Texas, northern Coahula, and northern Nuevo Leon (Dixon and Dixon, 1957).

• Biogeographic Regions
• nearctic nearctic
  • native native
• neotropical neotropical
  • native native

Habitat

White-tailed Kites can be found in a variety of habitats throughout North and Central America including grasslands, open fields, marshes, open groves, orchards, and river valleys. They commonly perch on posts, exposed branches, and in treetops (Dixon and Dixon, 1957)(Sibley, 2014). They typically nest in, but are not limited to, live oak, avocado, orange, cottonwood, and sycamore trees about 20-50 feet above ground (Pickwell, 1930). White-tailed Kites choose habitats that contain a high density of rodents and small mammals (Dixon and Dixon, 1957).

• Habitat Regions
• temperate temperate
• tropical tropical
• terrestrial terrestrial

• Terrestrial Biomes
• savanna or grassland savanna or grassland
• chaparral chaparral
• scrub forest scrub forest

• Wetlands
• marsh marsh

• Other Habitat Features
• agricultural agricultural
• riparian riparian

Physical Description

The adult White-tailed Kite can be identified by its all white body and head, and grey wings with black shoulder patches. Noticeable wing features while in flight include pointed wing tips, grey to black primaries, black primary coverts, and white secondaries and coverts. They have a long tail which is all white. Another easily identifiable feature of the White-tailed Kite is its red eyes surrounded by grey-black patches. The White-tailed Kite is not a sexually dimorphic raptor, males and females look similar. Juveniles can be identified by their cinnamon brown washed breast and crown as well as having speckled brown shoulder patches.

• Other Physical Features
• endothermic endothermic
• bilateral symmetry bilateral symmetry

• Sexual Dimorphism
• sexes alike

Reproduction

Male White-tailed Kites will attempt to pair with a female by hovering near her in a "V" formation and calling, and perching near her and bring prey to feed her. It has been recorded that Kites start pairing in December. A pair will choose a nest site together. The female will build the nest, but the male may also participate by bringing back nesting material. Many times, nests are hidden from below and exposed from above. Nests are described as loose structures compiled from dead branches and twigs lined with straw and grass. Usually, the nesting and incubation period begins around January and lasts until September. A pair may nest a second time during the breeding season and continue into the next season, or find a new partner.

• Mating System
• monogamous monogamous

The average clutch size is four eggs. Eggs are white and speckled with warm brow, between 1.5 and 1.8 inches long, and around 1.3 inches in length. The incubation period usually lasts between 30 and 32 days. During incubation, the male will often bring food to the female. Hatchlings are covered with tan-yellow down feathers. To wean the young out of the nest, the parents will viciously fly into them to drive them out. Offspring are able to fly 30-35 days after hatching, but are known to return to the nest for some time to sleep or eat. Monogamous pairs may nest a second time in the same breeding season. However, they may not continue as a pair for future breeding seasons.

• Key Reproductive Features
• iteroparous iteroparous
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual sexual
• oviparous oviparous

During the incubation period, the male White-tailed Kite will perch nearby and bring the female food. Hatchlings are helpless after they emerge from the egg. New hatchlings are brooded by the female, while the male does the foraging and brings the female food to feed to the young. As the young mature, the male will drop prey into the nest while the young feed independently. The female Kite is constantly guarding the nest and will attack any raptor who seems to be a threat. Occasionally, the male will join in on the attacks.

• Parental Investment
• altricial altricial
• male parental care male parental care
• female parental care female parental care
• pre-fertilization
  • provisioning
  • protecting
    • male
• pre-hatching/birth
  • provisioning
    • male
  • protecting
    • male
    • female
• post-independence association with parents

Behavior

White-tailed Kites are often seen in flight, rapidly beating their wings, over open fields looking for prey. They are known for a behavior called "kiting", where they hold a stationary position in the air while fluttering their wings. White-tailed Kites are territorial, however, they are tolerable towards other nearby Kites. Rarely, a male Kite will challenge another male entering its territory by locking talons and tumbling towards the ground. Generally, White-tailed Kites are more social compared to other raptors. In addition, they have been known to partake in roosting behaviors during the non-breeding season. The Kites will gather at dusk in the highest points in trees in groups up to 100 individuals, as recorded.

• Key Behaviors
• arboreal arboreal
• flies
• motile motile
• territorial territorial
• social social

Home Range

White-tailed Kites home range is usually very small and depends highly on food availability. They choose to nest near open areas on the edge of forests with large amounts of small mammals. They are fairly communal and aren't too territorial. Nests have been found to be as close as 200 meters apart.

Communication and Perception

White-tailed Kites are known to make rough, grating calls in a variety of lengths. They can also be heard making quiet, whistled "yelp" or "keep-keep-keep" calls and plaintive "kreep" calls. They acknowledge or announce presence with a low "kewp". Many times, the male makes this call as he approaches the female with food and likely the female responds in the same manner. Both sexes give this call under many circumstances where there is presence of the other sex including preening. White-tailed Kites communicate unease feelings with "eee-grack". The "eee" is a high pitched whistle, while the "grack" is low, guttural, and raspy. This sound is made during copulation, hunting, or the presence of another bird or human. There seems to be no apparent difference in sounds between males and females.

• Communication Channels
• acoustic acoustic

• Perception Channels
• visual visual
• tactile tactile
• acoustic acoustic
• chemical chemical

Food Habits

White-tailed Kites are carnivorous, feeding mostly on small rodents such as field mice Mus musculus , shrews Soricidae , young rabbits Oryctolagus cuniculus , rats Rattus , pocket gophers Geomyidae , and especially voles Microtus . In rare occasions, they will feed on other birds, frogs, lizards, and insects. Kites hunt by facing the wind and hovering above the ground while scanning for movement. When a prey item is detected, the White-tailed Kite will dive down and grab it with its talons with its wings held up.

• Primary Diet
• carnivore carnivore
  • eats terrestrial vertebrates
  • insectivore insectivore

• Animal Foods
• birds
• mammals
• amphibians
• reptiles
• insects

Predation

The main predators of White-tailed Kites are crows and other raptors. Crows ( Corvus brachyrhynchos ) have been known to scavenge White-tailed Kite nests, destroying their eggs or even killing their young. If a Kite is threatened, they will let out a plaintive whistle attack a predator aerially, causing the predator to leave in a hurry.

• Anti-predator Adaptations
• aposematic aposematic

Ecosystem Roles

Elanus leucurus is a bird of prey, they feed on small mammals. White-tailed kites help manage the rodent populations including voles microtus , harvest mice Micromys minutus , and pocket gophers Geomyidae . They may occasionally prey on snakes Serpentes , lizards Lacertilia , frogs Anura , and insects Insecta which helps maintain those populations. It has also been recorded on many occasions that crows Corvus will feed on the White-tailed kite's eggs and young.

Economic Importance for Humans: Positive

White-tailed kites feed on small rodents that are abundant in agricultural fields such as voles Microtus , harvest mice Reithrodontomys megalotis , house mice Mus musculus , meadow mice Micromys californicus and pocket gophers Geomys bursarius . Farmers who own these fields benefit from this predation since small rodents usually do a great amount of damage to them.

• Positive Impacts
• controls pest population

Economic Importance for Humans: Negative

There are no known adverse effects of Elanus leucurus on humans.

Conservation Status

The White-tailed kite was on the verge of extinction between 1930-1940 due to habitat loss, egg collections, and shooting. However, their populations have since rebounded (Iko et al., 2003) (Warner and Rudd, 1975). It is thought that this population increase may be the result of their ability to inhabit areas where they have previously not occupied and the introduction of house mice from Europe (Warner and Rudd, 1975). Rodent prey are also more abundant in areas where wetlands have been converted to agricultural fields, aiding in the White-tailed Kite's recovery (Iko et al., 2003). Now, the current status of White-tailed Kite is of least concern according to the IUCN Redlist and they are protected under the US Migratory Bird Act.

Additional Links

Encyclopedia of Life

Contributors

Mandy Mellinger (author), Northern Michigan University, Alec Lindsay (editor), Northern Michigan University, Tanya Dewey (editor), University of Michigan-Ann Arbor.

References

Clark, W., R. Banks. 1992. The Taxonomic Status of the White-Tailed Kite. The Quarterly Magazine of Ornithology , 104 / 4: 571-816. Accessed January 28, 2020 at https://sora.unm.edu/sites/default/files/journals/wilson/v104n04/p0571-p0579.pdf .

Dixon, R., J. Dixon. 1957. Natural History of the White-Tailed Kite. The Condor , 59 / 3: 156-165. Accessed January 28, 2020 at https://www.jstor.org/stable/1364721 .

Hawbecker, A. 1942. A Life History Study of the White-Tailed Kite. The Condor , 44 / 6: 267-276. Accessed January 31, 2020 at https://academic.oup.com/condor/article/44/6/267-276/5251402 .

Iko, W., C. Kester, C. Bern, R. Stendell, R. Rye. 2003. Comparison of the white-tailed kite food web dynamics among various habitats in California using stable isotope analysis . Boulder, CO: Geological Society of America. Accessed April 20, 2020 at https://pubs.er.usgs.gov/publication/70006805 .

Moore, R. 1941. Habits of the White-tailed Kite. The Auk , 58 / 4: 453-462. Accessed January 31, 2020 at https://academic.oup.com/auk/article/58/4/453-462/5239199 .

Pickwell, G. 1930. The White-Tailed Kite. The Condor , 32 / 5: 221-239. Accessed January 28, 2020 at https://www.jstor.org/stable/1363394 .

Schlatter, R., B. Toro, J. Yanez, F. Jaksic. 1980. Prey of the White-Tailed Kite in Central Chile and Its Relation to the Hunting Habitat. The Auk , 97 / 1: 186-190. Accessed January 28, 2020 at https://academic.oup.com/auk/article/97/1/186/5188621 .

Sibley, D. 2014. The Sibley Guide to Birds: Second Edition . Random House LLC, New York, New York: Alfred A. Knopf.

Warner, J., R. Rudd. 1975. Hunting by the White-Tailed Kite (Elanus leucurus). The Condor , 77 / 2: 226-230. Accessed January 28, 2020 at https://www.jstor.org/stable/1365804 .

Watson, F. 1940. A Behavior Study of the White-Tailed Kite. The Condor , 42 / 6: 295-304. Accessed January 31, 2020 at https://www.jstor.org/stable/1364162 .

Cornell University. 2019. "White-tailed Kite Identification" (On-line). All About Birds, The Cornell Lab of Ornithology. Accessed February 16, 2020 at https://www.allaboutbirds.org/guide/White-tailed_Kite/id .

National Audubon Society. 2020. "White-tailed Kite" (On-line). Audubon. Accessed February 16, 2020 at https://www.audubon.org/field-guide/bird/white-tailed-kite# .