Snail kite | |
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Adult male | |
Adult female, Panama | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Accipitriformes |
Family: | Accipitridae |
Genus: | Rostrhamus Lesson, 1830 |
Species: | R. sociabilis |
Binomial name | |
Rostrhamus sociabilis (Vieillot, 1817) | |
Subspecies [2] | |
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Range of R. sociabilis All-year resident Breeding only range Area of breeding and vagrancy |
The snail kite (Rostrhamus sociabilis) is a bird of prey within the family Accipitridae, which also includes the eagles, hawks, and Old World vultures. Its relative, the slender-billed kite, is now again placed in Helicolestes, making the genus Rostrhamus monotypic. Usually, it is placed in the milvine kites, but the validity of that grouping is under investigation.
Snail kites are 36 to 48 cm (14 to 19 in) long with a 99–120 cm (39–47 in) wingspan. They weigh from 300 to 570 g (11 to 20 oz). [3] [4] There is very limited sexual dimorphism, with the female averaging only 3% larger than the male. They have long, broad, and rounded wings, which measure 29–33 cm (11–13 in) each. Its tail is long, at 16–21 cm (6.3–8.3 in), with a white rump and undertail coverts. The dark, deeply hooked beak, measuring 2.9–4 cm (1.1–1.6 in) is an adaptation to its diet. The tarsus is relatively long as well, measuring 3.6–5.7 cm (1.4–2.2 in). [4]
The adult male has dark blue-gray plumage with darker flight feathers. The legs and cere are red. The adult female has dark brown upperparts and heavily streaked pale underparts. She has a whitish face with darker areas behind and above the eye. The legs and cere are yellow or orange. The juvenile is similar to an adult female, but the crown is streaked. Adults have red or orangish-brown irises, while juveniles have dark brown irises. [5]
It flies slowly with its head facing downwards, looking for its main food, the large apple snails. For this reason, it is considered a molluscivore.
Lerner and Mindell (2005) found R. sociabilis sister to Geranospiza caerulescens , and that those two along with Ictinea plumbea were basal to both the Buteogallus and Buteo clades. They concluded that Rostrhamus belonged in Buteoninae (sensu stricto) and not in Milvinae, but noted that more investigation was needed. [6]
The snail kite breeds in tropical South America, the Caribbean, and central and southern Florida in the United States. It is resident all-year round in most of its range, but the southernmost population migrates north in winter and the Caribbean birds disperse widely outside the breeding season.
It nests in a bush or on the ground, laying three to four eggs.
The snail kite is a locally endangered species in the Florida Everglades, with a population of less than 400 breeding pairs. Research has demonstrated that water-level control in the Everglades is depleting the population of apple snails. [7] However, this species is not generally threatened over its extensive range.
In fact, it might be locally increasing in numbers, such as in Central America. In El Salvador, it was first recorded in 1996. Since then, it has been regularly sighted, including immature birds, suggesting a resident breeding population might already exist in that country. On the other hand, most records are outside the breeding season, more indicative of post-breeding dispersal. In El Salvador, the species can be observed during the winter months at Embalse Cerrón Grande, Laguna El Jocotal, and especially Lago de Güija. Pomacea flagellata apple snails were propagated in El Salvador between 1982 and 1986 as food for fish stocks, and it seems that the widespread presence of high numbers of these snails has not gone unnoticed by the snail kite. [8]
Due to the drainage and habitat destruction of the Everglades, they were one of the first species put on the US Fish and Wildlife Service's endangered species list [9] on 11 March 1967. [10] The snail kite continued to decline, reaching a population of less than 800 in 2007. Their population gradually rebounded after the invasive snail species Pomacea maculata began to flourish in the Everglades wetlands and served as a new food source for the snail kites, reaching a count of 3,000 snail kites in 2022. Everglades conservation efforts over the course of 30 years and costing over US$20 billion also contributed to restoring native vegetation of the snail kites' habitats and flow of water in marshes. [9]
This is a gregarious bird of freshwater wetlands, forming large winter roosts. Its diet consists almost exclusively of apple snails, especially the species Pomacea paludosa in Florida, and species of the genus Marisa . [11] [12]
Snail kites have been observed eating other prey items in Florida, including crayfish in the genus Procambarus , crabs in the genus Dilocarcinus, black crappie, small turtles and rodents. [13] [12] [11] It is believed that snail kites turn to these alternatives only when apple snails become scarce, such as during drought, [14] but further study is needed. On 14 May 2007, a birder photographed a snail kite feeding at a red swamp crayfish farm in Clarendon County, South Carolina. [15] [16]
The presence of the large introduced Pomacea maculata in Florida has led the snail kites in North America to develop larger bodies and beaks to better eat the snail, a case of rapid evolution. [17] These non-native snails provide a better food source than the smaller native snails and have had a positive effect on the kites' populations. [18]
The Accipitridae is one of the three families within the order Accipitriformes, and is a family of small to large birds of prey with strongly hooked bills and variable morphology based on diet. They feed on a range of prey items from insects to medium-sized mammals, with a number feeding on carrion and a few feeding on fruit. The Accipitridae have a cosmopolitan distribution, being found on all the world's continents and a number of oceanic island groups. Some species are migratory. The family contains 255 species which are divided into 70 genera.
Everglades National Park is an American national park that protects the southern twenty percent of the original Everglades in Florida. The park is the largest tropical wilderness in the United States and the largest wilderness of any kind east of the Mississippi River. An average of one million people visit the park each year. Everglades is the third-largest national park in the contiguous United States after Death Valley and Yellowstone. UNESCO declared the Everglades & Dry Tortugas Biosphere Reserve in 1976 and listed the park as a World Heritage Site in 1979, and the Ramsar Convention included the park on its list of Wetlands of International Importance in 1987. Everglades is one of only three locations in the world to appear on all three lists.
Kite is the common name for certain birds of prey in the family Accipitridae, particularly in subfamilies Milvinae, Elaninae, and Perninae. The term is derived from Old English cȳta, from the Proto-Indo-European root *gū- , "screech."
The black-shouldered kite, also known as the Australian black-shouldered kite, is a small raptor found in open habitats throughout Australia. It resembles similar species found in Africa, Eurasia and North America, including the black-winged kite, a species that has in the past also been called "black-shouldered kite". Measuring around 35 cm (14 in) in length, with a wingspan of 80–100 cm (31–39 in), the adult black-shouldered kite has predominantly grey-white plumage and prominent black markings above its red eyes. It gains its name from the black patches on its wings. The primary call is a clear whistle, uttered in flight and while hovering. It can be confused with the related letter-winged kite in Australia, which is distinguished by the striking black markings under its wings.
The limpkin, also called carrao, courlan, and crying bird, is a large wading bird related to rails and cranes, and the only extant species in the family Aramidae. It is found mostly in wetlands in warm parts of the Americas, from Florida to northern Argentina, but has been spotted as far north as Wisconsin. It feeds on molluscs, with the diet dominated by apple snails of the genus Pomacea. Its name derives from its seeming limp when it walks.
The lizard buzzard or lizard hawk, is a bird of prey in the family Accipitridae. It is native to Sub-Saharan Africa. Despite its name, it may be more closely related to the Accipiter hawks than the Buteo buzzards.
The grey-headed fish eagle is a fish-eating bird of prey from South East Asia. It is a large stocky raptor with adults having dark brown upper body, grey head and lighter underbelly and white legs. Juveniles are paler with darker streaking. It is often confused with the lesser fish eagle and the Pallas's fish eagle. The lesser fish eagle is similar in plumage but smaller and the Pallas's fish eagle shares the same habitat and feeding behaviour but is larger with longer wings and darker underparts. Is often called tank eagle in Sri Lanka due to its fondness for irrigation tanks.
The Mississippi kite is a small bird of prey in the family Accipitridae. Mississippi kites have narrow, pointed wings and are graceful in flight, often appearing to float in the air. It is common to see several circling in the same area.
The white-collared kite is an Endangered species of bird in tribe Pernini and subfamily Perninae of family Accipitridae, the diurnal raptors. It is endemic to northeastern Brazil.
The slender-billed kite is a South American bird of prey in the family Accipitridae. It is found along a scattered range in forested parts of tropical northern and central South America, and far eastern Panama. The species was recategorized into and has once again been removed from the genus Rostrhamus.
The hook-billed kite, is a bird of prey in the family Accipitridae, which also includes many other diurnal raptors such as kites, eagles, and harriers. It occurs in the Americas, including the Rio Grande Valley of Texas in the United States, Mexico, the Caribbean, Central America, and tropical South America.
The square-tailed kite is a medium-sized bird of prey in the family Accipitridae, which also includes many other diurnal raptors such as kites, eagles and harriers.
Florida State Road 7 (SR 7) is a major north–south artery in South Florida connecting U.S. Highway 41 in the Little Havana section of Miami with 60th Street in Loxahatchee. All but the northernmost 6.5 miles (10.5 km) is instead signed as US 441, and has been since 1950.
The Cuban kite is a bird of prey in the family Accipitridae which also includes many other diurnal raptors such as kites, eagles and harriers. It is endemic to Cuba.
The letter-winged kite is a small, rare and irruptive bird of prey that is found only in Australia. Measuring around 35 cm (14 in) in length with a wingspan of 84–100 cm (33–39 in), the adult letter-winged kite has predominantly pale grey and white plumage and prominent black rings around its red eyes. Its name derives from its highly distinctive black underwing pattern of a shallow 'M' or 'W' shape, visible when in flight. This distinguishes it from the otherwise similar black-shouldered kite. This species is also the only nocturnal species within the order Accipitriformes despite few differences found in its visual anatomy to other closely related kites.
The black-collared hawk is a species of bird of prey in the family Accipitridae. It is monotypic within the genus Busarellus. It has a widespread range of presence, from western Mexico to Uruguay. Its natural habitats are subtropical or tropical moist lowland forests, subtropical or tropical swamps, and swamps.
The rufous-thighed kite is a species of bird of prey in subfamily Accipitrinae, the "true" hawks, of family Accipitridae. It is found regularly in Argentina, Bolivia, Brazil, Guyana, Paraguay, and Suriname and as a vagrant in Colombia, French Guiana, and Venezuela.
Snail is usually one of almost all members of the molluscan class Gastropoda which have coiled shells.
Pomacea canaliculata, commonly known as the golden apple snail or the channeled apple snail, is a species of large freshwater snail with gills and an operculum, an aquatic gastropod mollusc in the family Ampullariidae, the apple snails. South American in origin, this species is considered to be in the top 100 of the "World's Worst Invasive Alien Species". It is also ranked as the 40th worst alien species in Europe and the worst alien species of gastropod in Europe.
Pomacea maculata is a species of large freshwater snail with an operculum, an aquatic gastropod mollusk in the family Ampullariidae, the apple snails.