Audubon's crested caracara (Caracara plancus audubonii) in Florida. Courtesy J.N. Layne | |
The number of Florida caracaras is believed to have undergone a substantial decline from the early historic level in the 1950's and 1960's (Layne in press), with the total state population estimated at 250 in the early 1950's (Sprunt 1954) and fewer than 100 birds in the late 1960's (Heinzman 1970). Based on the appar-ent continuing decrease in its numbers, Florida's population of Audubon's crested caracara was federally listed as threatened in 1987 (Federal Register 1987). As part of a general study of the life history, ecology, and behavior of the caracara in Florida, I monitored its distribution and population status from 1972 to 1991. |
Fig. 1. Breeding range of Audubon's crested caracara in Florida based on records from 1987 to 1991; range boundaries shown by Howell (1932), and main species' range in western United States. | |
The breeding range of Audubon's crested caracara in Florida (Fig. 1), based on records from the most recent 5-year period of the study (1987-91), did not differ significantly from that during 1973-76 (Layne 1978). Caracaras were documented in 20 counties in central peninsular Florida, with most locations in the same 5-county area as in the earlier years. Counties with 10% or more of the 183 estimated locations during 1987-91 included (number of locations in parentheses) Glades (41), Highlands (34), Okeechobee (23), and Osceola (18). The data indicate no obvious change has occurred in the overall range or core area of the distribution of the caracara in Florida from that shown by Howell (1932). As there had been relatively little alteration of the natural habitats of the state up to that time, Howell's range map is assumed to reflect the early historical distribution. |
References | |
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Federal Register. 1987. Endangered and threatened wildlife and plants: threatened status for the Florida population of Audubon's crested caracara. Federal Register 52(128):25229-25232. Heinzman, G. 1970. The caracara survey, a four year report. Florida Naturalist 43:149. Howell, A.H. 1932. Florida bird life. Florida Department of Game and Freshwater Fish, Tallahassee. 479 pp. |
Layne, J.N. 1978. Audubon's caracara (Caracara cheriway auduboni). Pages 34-36 in H.W. Kale II, ed. Birds, rare and endangered biota of Florida. Vol. 2. University Press of Florida, Gainesville. Layne, J.N. Audubon's crested caracara (Polyborus plancus audubonii). In J.A. Rodgers, H.W. Kale II, and H. Smith, eds. Birds, rare and endangered biota of Florida. 2nd ed. University Press of Florida, Gainesville. In press. Sprunt, A., Jr. 1954. Florida bird life. Coward-McCann, New York. 527 pp. |