Elanoides forficatus (Linnaeus)
Fork-tailed Hawk, Swallow-tailed Hawk, Snake Hawk, Fish Hawk.
Breeder. Uncommon and local in summer, and rare in early fall in Inland Coastal Plain and Gulf Coast regions. Occasional in spring and summer in Tennessee Valley and Mountain regions. HIGH CONSERVATION CONCERN.
A medium-sized (48-61 cm [19-24 in.]) raptor readily identified by long pointed wings, and deeply forked tail. Sexes similar; head, neck, underparts, and under-wing coverts white; back, upper-wing coverts, and all wing and tail feathers black, but appear bluish in direct sunlight. Scapulars, marginal coverts, and lesser upper-secondary coverts darker than back and have a blackish iridescent sheen; bill and legs dark. Juveniles similar to adults except for buff streaking on head, neck, and chest, narrow white margins on flight feathers, and considerably shorter tail (Meyer 1995; Meyer and Collopy 1995, 1996). Typical call a series of two to four notes, klee-klee-klee-klee, usually given when disturbed around nest and roost sites, and during agonistic encounters or courtship. Other vocalizations include tew-whee, eeep, and a soft chitter (Meyer 1995). Two subspecies recognized but debated, E. f. forficatus and E. f. yetapa, with only the nominate race occurring in the southeastern United States (Meyer and Collopy 1996).
Northern subspecies (E. f. forficatus) formerly bred throughout the Southeast and along the major drainages of the Mississippi Valley as far north as Minnesota, and as far east as Ohio, encompassing as many as 21 states.Today, breed locally only in seven southeastern states from South Carolina south to the upper Florida Keys, and west along the Gulf Coastal Plain to Louisiana and eastern Texas (Meyer and Collopy 1996). In Alabama, found primarily in the floodplain forests along the lower Alabama and lower Tombigbee Rivers, and Mobile-Tensaw River Delta (Soehren 1998). May also be found in similar habitats along Conecuh, and possibly Pea, Choctawhatchee, and lower Chattahoochee River floodplains. South American subspecies (E. f. yetapa)breeds from southern Mexico to northern Argentina and southeastern Brazil. Both subspecies winter locally in northern two-thirds of South America (Meyer 1995).
For nesting, requires tall, accessible trees adjacent to open foraging areas (Meyer 1995). Myriad of habitats may be used, but essential key features include uneven-aged forest stands adjacent to mosaics of freshwater wetland areas with an abundance of small prey (Meyer 1998); physical structure of landscape more important than specific plant community types. Edges of pine forest adjacent to riparian and swamp forest especially important (Meyer 1995). In Alabama, prefers to nest in tall deciduous trees on natural levees along major river floodplain systems, and in mature cypress-hardwood swamps within the Mobile-Tensaw River Delta (E. Soehren, pers. obs.).
Forage on the wing and have a diet consisting of insects, frogs, lizards, nestling birds, snakes, and small mammals. Adults generally eat large flying insects, but often feed their young small vertebrates (Meyer 1995; Meyer and Collopy, 1995, 1996).
LIFE HISTORY AND ECOLOGY:
Among the first neotropical migrants to arrive in United States. Arrival dates range from mid-February in south Florida to late March elsewhere (Meyer 1995). Arrive on breeding grounds already paired and are believed to be monogamous. Often return to same territory occupied from previous year. Courtship includes dive chasing accompanied by loud calling by both sexes. Usually, one or two nonbreeding adults associate with nesting pair and often contribute food items and nest material to breeders (Meyer and Collopy 1995, 1996). Both adults build nest, which is composed primarily of small sticks, wasp nests, lichens, and Spanish moss; usually situated in top of tallest trees within forest stand. Often nest in loose colonies that typically range between two to five nesting pairs over a broad area (Meyer 1995). Neighborhood night roosts consisting of numerous birds (primarily nonbreeding adults) are formed near nest sites and remain active throughout entire breeding cycle (Meyer 1998). Two creamy white eggs, variably blotched with dark brown to reddish brown, typically laid and incubated by both adults for approximately 28 days. Young hatch asynchronously and are brooded by both adults during first week. Following first week, male relinquishes brooding duties and commits to hunting exclusively. Male brings food items to female who in turn tears food and feeds young. As time passes, female broods less and commits more to hunting. Young fledge approximately six weeks after hatching, but parental feeding continues until onset of migration. Only one brood raised each year (Meyer 1995, Meyer and Collopy 1995, 1996). In Alabama, breeds between third week of March and first week of July (E. Soehren, pers. obs.). Following breeding, birds disperse from nesting area and spend time foraging in groups, which may vary in size depending on prey availability. Large communal roosts develop near foraging areas and remain active until migration. Same communal roost sites may be used for many years and are very important for social interaction and conditioning prior to migration (Meyer 1998). Depart from roost sites from late July to mid-August with most birds leaving by early September (Meyer 1995).
BASIS FOR STATUS CLASSIFICATION:
United States population has declined significantly in size and distribution since the early twentieth century, and trends for remaining, disjunct populations in seven southeastern states where still known to occur presently unknown. Loss of habitat, indiscriminate shooting, and low reproductive rates believed to be primary reasons for decline (Meyer 1995, 1998, Meyer and Collopy 1995, 1996). Probably no more than 5,000 individuals, including nonbreeding adults and fledged young, remain at the end of each nesting season. Greatest threat in Alabama is loss or degradation of habitat. Social behavior and strong philopatry to specific breeding and roost areas also increases susceptibility to disturbance (Meyer 1998). Currently listed as Extirpated in Arkansas, Endangered in South Carolina, Threatened in Florida, Rare in Georgia, Imperiled in Mississippi, a Species of Conservation Concern in Louisiana, and Threatened in Texas (Meyer and Collopy 1996). Also on Partners In Flight’s Watchlist designated as an extremely high-priority species in need of conservation attention. Current priority designation in Alabama based on low relative abundance, locally clumped distribution, specialized habitat requirements, and potential threats of disturbance or destruction to breeding and communal roost locations.
Eric C. Soehren