Elanoides forficatus

A slim diurnal raptor (hooked bill, strong talons) with narrow pointed wings and a black, strongly forked tail; head, breast, belly, and underwing coverts are white, flight feathers and back are black; young are streaked on the head and breast; average length 58 cm, wingspan 122 cm (NGS 1983).

No other sympatric bird has all of the following characteristics: white head and belly, black wings with white underwing coverts, and a deeply forked black tail.

This species occupies diverse vegetation types, from sea level to elevations up to 1,850 meters; occasionally individuals wander up to 3,000 meters (Stiles and Skutch 1989). Key features of habitat include tall, accessible trees for nesting and open areas for foraging; arid areas are avoided (Meyer 1995). In the United States, nesting and foraging habitats include various pine forests and savannas, cypress swamps and savannas, cypress-hardwood swamps, hardwood hammocks, mangrove (Avicennia) swamps, narrow riparian forests, prairies, and freshwater and brackish marshes. In the tropics, this kite occurs in humid lowland and upland forests, riparian forests, cloud forests, and pine forests (Meyer 1995, Stiles and Skutch 1989).

Nests are near the tops of trees that are higher than the surrounding stand, presumably to provide easier access to the nest (Brown et al. 1997, Snyder 1974, Meyer 1995, Meyer and Collopy 1995). In south Florida, nest trees were significantly taller than random trees (Meyer and Collopy 1995). Nests most often are 8-38 meters above the ground (Brown et al. 1997, Snyder 1974, Stiles and Skutch 1989). The average nest height in South Carolina was 23 meters; in Florida mean nest height ranged from 18.2-21.7 meters (Cely and Sorrow 1990, Meyer and Collopy 1995).

Pines are the preferred nest trees. Of 151 U.S. nests, 86 percent were in pines, 7 percent in cypress (Taxodium spp.) and 7 percent in mangrove (Meyer 1995). Most nests in South Carolina, Mississippi, and Louisiana were in loblolly pine (Pinus taeda; Cely and Sorrow 1990, Meyer 1995). Elsewhere in Louisiana and Texas, nests have been found in cottonwood (Populus deltoides) and water oak (Quercus nigra; Brown et al. 1997, Meyer 1995). In south Florida, 51 percent of nests were in slash pine (Pinus elliottii), 37 percent in cypress, 12 percent in Australian pine (Casuarina equisetifolia) and 6 percent in bay (Persea spp.; Meyer 1995).

This species roosts communally (up to 30 individuals) at night during the nesting period and prior to migration (Bensen 1992, Haverschmidt 1977, Millsap 1987, Meyer 1995, Meyer 1998, Meyer and Collopy 1995).

Potential predators, especially of eggs and young, include common crow, turkey vulture, black vulture, red-shouldered hawk, peregrine falcon, sharp-shinned hawk, bald eagle, osprey, short-tailed hawk, red-tailed hawk, great horned owl, barred owl, raccoon, and monkeys (Gerhardt et al. 1991, cited in Meyer 1995, Meyer and Collopy 1995, Short 1974, Snyder 1974).

Strong winds, especially those associated with storms, can blow young from the nest or topple tall trees used for nesting (Cely and Sorrow 1990, Snyder 1974).

Nesting occurs in loose colonies, in groups of 2-5 nests, generally 75-700 meters apart (Meyer 1995). In south Florida, nearest nests averaged 673-730 meters apart (Meyer and Collopy 1995). Individuals often nest near sites that were used previously for nesting by swallow-tailed kites. In south Florida, 77 percent of nests sites were re-used and at 23.5 percent of these the original nest was re-used after being re-furbished. However, because birds were unmarked it is not known if sites were re-used by previous residents (Meyer and Collopy 1995).

Nesting occurs February-May in Costa rica and from early March-early June in the United States (Meyer 1995, Meyer and Collopy 1996, Stiles and Skutch 1989). Clutch size ranges from two to four eggs but is typically two (Terres 1991). The average of 151 U.S. clutches was 2.12 eggs, that of 11 Florida clutches was 1.91 eggs, and that of 18 Guatemala clutches was 1.83 eggs (Gerhardt et al. 1997, Meyer 1995). Incubation, conducted principally by the female, takes approximately 28 days in Florida and averages 31.5 days in Guatemala. Incubation begins when the first egg is laid and hatching is asynchronous (Gerhardt et al. 1997, Snyder 1974). The young are brooded by both sexes, although principally by the female. The nestling period is 36-42 days (Snyder 1974). There is no evidence of second-clutching even after nest or egg failure (Meyer 1995). Brood reduction sometimes occurs when younger nestlings starve or are killed outright by larger nestlings (Gerhardt et al. 1997, Meyer 1995).

Estimates of nesting success (percent of nests that fledged greater than or equal to 1 young) include 33 percent for Guatemala (Gerhardt et al. 1997), 41-80 percent for Florida (Meyer and Collopy 1995), and 72 percent for South Carolina (Cely and Sorrow 1990). Productivity estimates (number of young fledged per nest) for these same studies vary from 0.33 (Guatemala), 0.48-1.27 (Florida), to 1.14 (South Carolina). In Florida, nest success varied by species of nest tree: 78 percent for cypress, 60 percent for slash pine and 17 percent for Australian pine. In addition, nests in more flexible trees failed more often due to wind than nests in more rigid trees (Meyer and Collopy 1995).