American Kestrel (Falco sparverius) Science Article 3 abstract The degree of dimorphism between males and females has been examined in a number of raptors (Storer 1966, Reynolds 1972, Balgooyen 1976, Snyder and Wiley 1976), but few studies have reported the amount of dimorphism between mated pairs of birds. If the maintenance of a size difference […]
Category: Falconiformes
EASTERN SCREECH-OWL HATCHES AN AMERICAN KESTREL
American Kestrel (Falco sparverius) Science Article 16 abstract An Eastern Screech-Owl (Otus asio) was found incubating her own egg and that of a Southeastern American Kestrel (Falco sparverius paulus) in late March 1995. Three owlets and the kestrels uccessfully hatched in early May; all appeared normal. The kestrel was not present in the nest box […]
Plasma corticosterone in American kestrel siblings: effects of age,hatching order, and hatching asynchrony
American Kestrel (Falco sparverius) Science Article 18 abstract Although it is well documented that hatching asynchrony in birds can lead to competitive and developmental hierarchies, potentiallygreatly affecting growth and survival of nestlings, hatching asynchrony may also precipitate modulations in neuroendocrine developmentor function. Here we examine sibling variation in adrenocortical function in postnatally developing, asynchronously hatching […]
Haemoproteus tinnunculus in the American Kestrel (Falco sparverius)
American Kestrel (Falco sparverius) Science Article 2 abstract Unspecified species of Haemoproteus have been recorded from American Kestrels in Texas, Colorado and Panama; and Haemoproteus elani de Mello, 1935 has been recorded from kestrels in Oklahoma. However, there are no published identifications of Haemoproteus tinnunculus in this avian host in North America. This investigation reports […]
Sex-related differences in habitat selection in wintering American kestrels,Falco sparverius
American Kestrel (Falco sparverius) Science Article 1 abstract The American kestrel, Falco sparverius, has sex-related differences in habitat use during thenon-breeding season, with females occupying more open habitats than males. Two competinghypotheses have been proposed to explain this phenomenon: (1) males and females prefer differenthabitats, and (2) males and females prefer similar habitats, but larger […]
VOCAL DEVELOPMENT IN AMERICAN KESTREL (FALCO SPAR VERIUS) NESTLINGS
American Kestrel (Falco sparverius) Science Article 7 abstract We studied the acoustical characteristics of calls made by nestling American Kestrels (Falco sparverius). A total of 563 vocal samples was obtained from 88 chicks (49 males and 39 females) from 20 broods. Thirteen frequency, three numerical, and two temporal characteristics were measured using audio spectrography. Discriminant […]
The effects of temperature and artificial rain on the metabolism ofAmerican kestrels (Falco sparverius)
American Kestrel (Falco sparverius) Science Article 5 abstract The effect of rainfall on the metabolism of birds is poorly understood. We measured the metabolism as rate of oxygen consumption (V? O2)of four male and four female American kestrels (Falco sparverius) using open-circuit respirometry. We measured V? O2 during the spring atambient temperatures (Ta) of 5, […]
Carotenoid concentration and coloration of AmericanKestrels (Falco sparverius) disrupted by experimentalexposure to PCBs
American Kestrel (Falco sparverius) Science Article 6 abstract Bright coloration in birds is typically a sexually selected trait. Expression of suchtraits is sensitive to environmental factors, so they can function as bioindicators ofenvironmental contamination. Of particular value may be carotenoid-based colorationbecause it is commonly used as a social signal and these pigments have importanthealth functions. […]
American Kestrel Use of Pine Regeneration Stands in South Carolina
American Kestrel (Falco sparverius) Science Article 15 abstract The American Kestrel (Falco sparverius) is widely distributed across mostof the United States and is one of the most abundant of all North Americanraptors. Two subspecies of kestrels occur in the southeast, F. s. sparverius andthe rarer F. s. paulus. Amanda Allen Beheler and John B. Dunning, […]
Nest Success of Southeastern American KestrelsAssociated with Red-Cockaded Woodpeckers inOld-Growth Longleaf Pine Habitat in Northwest Florida
American Kestrel (Falco sparverius) Science Article 8 abstract The Southeastern American Kestrel (Falco sparverius paulus), anon-migratory subspecies of the widespread American Kestrel, has declined tothe point that it is listed as threatened in Florida, the state in which it is mostcommon. We studied the nesting biology of Southeastern American Kestrels in1999 and 2000 at Eglin […]