Planet of Birds

American Kestrel (Falco sparverius) Science Article 22 abstract No abstract Steenhof, K. and B.E. Peterson. 1997, J. Raptor Res. 31(3):274-297. Download article download full text (pdf)

American Kestrel (Falco sparverius) Science Article 23 abstract Antibody-mediated immune function in adult and recently fledged (30 to 33 d old) American kestrels (Falco sparverius) was examined in birds exposed directly, or only in ovo, to polychlorinated biphenyls (PCBs). In 1998, 9 mature male and 9 female kestrels were fed PCBs, whereas 9 females and […]

American Kestrel (Falco sparverius) Science Article 20 abstract Reports of birds exhibiting unusual incubation behaviors are perhaps not surprising, giventhe wide variety of physical properties that can elicit incubation responses in birds (seeBaerends and Drent 1982). Birds that normally are solitary nesters occasionally have beendocumented sharing the same nest site (Terres 1982, Fournier and Hines […]

American Kestrel (Falco sparverius) Science Article 19 abstract During 1983 and 1984 one adult member of 20 pairs of breeding kestrels was removedfrom the wild during the third week of incubation. We measured several variables, e.g., relative prey abundance, female body condition, territory size, amount of adjacent habitat, and time of removal at each experimental […]

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 […]

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 […]

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 […]

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 […]

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 […]

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 […]