Prairie Falcon

Taxobox
name = Prairie Falcon


image_width = 250px
image_caption = Adult bird showing underwing pattern. Photograph by Nick Anich.
status = LC
status_system = iucn3.1
regnum = Animalia
phylum = Chordata
classis = Aves
ordo = Falconiformes
familia = Falconidae
genus = "Falco"
species = "F. mexicanus"
binomial = "Falco mexicanus"
binomial_authority = Schlegel, 1850
synonyms ="Gennaia mexicana"
"Hierofalco mexicanus"

The Prairie Falcon ("Falco mexicanus") is a medium-sized falcon of western North America.

It is about the size of a Peregrine Falcon or a crow, with an average length of 40 cm (16 in), wingspan of 1 metre (40 in), and weight of 720 g (1.6 lb). As in all falcons, females are noticeably bigger than males.

It breeds from southern Manitoba, Saskatchewan, Alberta and south-central British Columbia south through the western United States – roughly between the eastern edge of the Mountain Time Zone and the Cascade Mountains, as well as the Central Valley of California – to the Mexican states of Baja California, Durango, and northern San Luis Potosí. It is much less migratory than the other North American falcons, but in winter it does withdraw somewhat from the northernmost and highest-elevation parts of its breeding range and spreads west to the deserts and Pacific coast of California, east to about the 100th meridian, and south to Baja California Sur, Jalisco, and Hidalgo.

Description

Plumage is warm gray-brown (sometimes called "sandy") above and pale with more or less dark mottling below. The darkest part of the upper side is the primary wing feathers; the lightest is the rump and tail, particularly the outer tail feathers. The head has a "moustache" mark like a Peregrine Falcon's but narrower, and a white line over the eye. A conspicuous character is that the axillars ("wingpits") and underwing coverts are black, except along the leading edge of the wing. This creates an effect of "struts" from the body along each wing.

Juveniles resemble adults except that they have dark streaks on the breast and belly and darker, less grayish upperparts.

Calls, heard mostly near the nest, are described as repetitive "kree kree kree…", "kik kik kik…", and the like, similar to the Peregrine's but higher-pitched.
[
United States Air Force Academy.] Experts can separate a distant Prairie Falcon from a Peregrine (generally the only similar species in its range) by its shape and flight style. The Prairie Falcon has a longer tail in proportion to its size; a more tubular, less stocky body; and the wing joint farther from the body. Its wingbeats are described as strong and shallow like the Peregrine's and having the same quick cadence, but stiffer and more mechanical.

ystematics

The Prairie Falcon outwardly resembles the Peregrine as well as the Old World "hierofalcons", especially the Saker Falcon. It was often considered the only New World member of the latter group. However, this is implausible for reasons of biogeography, and more recently, "Falco mexicanus" is considered an early aridland offshoot of the Peregrine Falcon lineage, much as the hierofalcons represent a later [Earlier results that suggested the hierofalcons to be the most ancient group of living falcons (Helbig "et al." 1994, Wink "et al." 1998) based on mtDNA cytochrome "b" sequence data were in error due to presence of a numt in the hierofalcons (Wink & Sauer-Gürth 2000).] divergence that similarly adapted to arid habitat. Thus, the similarities between the Prairie Falcon and the hierofalcons are a good example of convergent evolution, the present species and such Old World forms as the Saker and Lanner Falcons being not close relatives but ecological equivalents. [Helbig "et al." (1994), Wink "et al." (1998), Griffiths (1999), Wink & Sauer-Gürth (2000), Wink "et al." (2004), Nittinger "et al." (2005)]

Ecology and reproduction

The habitat is open country, especially arid, in summer including alpine tundra to shortgrass prairie and high desert. In winter it is more widespread, ranging to low deserts and occasionally to towns.

The Prairie Falcon eats mostly small mammals (especially in summer) and birds caught in flight. Like the Merlin, it often hunts by flying fast and low, at a height of only a metre or so, hoping to find surprised prey as it comes over the terrain or around a bush. Its cruising speed is estimated at 72 km/h (45 mph) and it accelerates in the chase. It also pursues prey sighted from a perch, again often flying very low. It typically catches birds by pursuing them in level flight and grasping them, less often knocking them down in spectacular dives like the Peregrine.

This species nests on cliff ledges, so breeding adults are local during the breeding season. The clutch averages four eggs, which are subelliptical and pinkish with brown, reddish-brown, and purplish dots. The incubation period is 31 days, beginning with the first egg. Incubation becomes more intense after later eggs are laid, somewhat evening out hatching times. As is typical for falcons, the female does most of the incubating and brooding, and the male brings most of the food, with the female also hunting after the young are 12 to 14 days old. The young fledge from 36 to 41 days after hatching and remain with the family for a short time before dispersing.

Relationship with humans

This species is often used in falconry. Although it is considered hard to train and unpredictable, it's the most popular falcon in the United States, due to its abundance and relative ease to acquire. It is also valued for its aggressiveness (Observers of wild birds and veterinarians agree with falconers that it's one of the most aggressive raptors). It is sometimes hybridized with Peregrine Falcons and Gyrfalcons.

The population is estimated to be stable or increasing at over 5000 pairs, with perhaps 200 pairs breeding at the Snake River Birds of Prey National Conservation Area in Idaho .

Footnotes

References

*|year=2004|id=49517|title=Falco mexicanus|downloaded=12 May 2006 Database entry includes justification for why this species is of least concern
* (2000): "The Sibley Guide to Birds". Alfred A. Knopf, New York. ISBN 0-679-45122-6
* (1989): "Hawks in Flight". Houghton Mifflin. ISBN 0-395-51022-8
* (1999): Phylogeny of the Falconidae inferred from molecular and morphological data. "Auk" 116(1): 116–130. [http://elibrary.unm.edu/sora/Auk/v116n01/p0116-p0130.pdf PDF fulltext]
* (1994): Phylogenetic relationships among falcon species (genus Falco) according to DNA sequence variation of the cytochrome b gene. "In:" aut|Meyburg, B.-U. & Chancellor, R.D. (eds.): "Raptor conservation today": 593-599. [http://www.uni-heidelberg.de/institute/fak14/ipmb/phazb/pubwink/1994/4.%201994.pdf PDF fulltext]
* (1995): "A Guide to the Birds of Mexico and Northern Central America". Oxford University Press, Oxford & New York. ISBN 0-19-854012-4
* (2005): Out of Africa? Phylogenetic relationships between "Falco biarmicus" and other hierofalcons (Aves Falconidae). "Journal of Zoological Systematics and Evolutionary Research" 43(4): 321-331. doi|10.1111/j.1439-0469.2005.00326.x [http://www.uni-heidelberg.de/institute/fak14/ipmb/phazb/pubwink/2005/28.2005.pdf PDF fulltext]
* (2000): Advances in the molecular systematics of African raptors. "In:" aut|Chancellor, R.D. & Meyburg, B.-U. (eds): "Raptors at Risk": 135-147. WWGBP/Hancock House, Berlin/Blaine. [http://www.uni-heidelberg.de/institute/fak14/ipmb/phazb/pubwink/2000/29.%202000.pdf PDF fulltext]
* (1998): Molecular systematics of holarctic raptors (Order Falconiformes). "In:" aut|Chancellor, R.D., Meyburg, B.-U. & Ferrero, J.J. (eds.): "Holarctic Birds of Prey": 29-48. Adenex & WWGBP. [http://www.uni-heidelberg.de/institute/fak14/ipmb/phazb/pubwink/1998/31.%201998.pdf PDF fulltext]
* (2004): Phylogenetic relationships in the Hierofalco complex (Saker-, Gyr-, Lanner-, Laggar Falcon). "In:" aut|Chancellor, R.D. & Meyburg, B.-U. (eds.): "Raptors Worldwide": 499-504. WWGBP, Berlin. [http://www.uni-heidelberg.de/institute/fak14/ipmb/phazb/pubwink/2004/27.2004.pdf PDF fulltext]

External links

* [http://www.birds.cornell.edu/AllAboutBirds/BirdGuide/Prairie_Falcon.html Cornell Lab of Ornithology - Prairie Falcon]
* [http://www.birdsofprey.blm.gov/nat-res/prfa.htm Extensive page from the Snake River Birds of Prey National Conservation Area]
* [http://www.ohiofalconry.org/prairiefalc.html Brief page from Ohio Falconry]
* [http://www.birdwatching-bliss.com/falcon-photos.html Picture of Prairie Falcon nestlings and other falcon photos]
* [http://www.mbr-pwrc.usgs.gov/id/framlst/i3550id.html USGS Patuxent Bird Identification InfoCenter - Prairie Falcon]
* [http://www.sdakotabirds.com/species/prairie_falcon_info.htm South Dakota Birds and Birding - Prairie Falcon Information and Photos]
* [http://vireo.acnatsci.org/search.html?Form=Search&SEARCHBY=Common&KEYWORDS=prairie+falcon&showwhat=images&AGE=All&SEX=All&ACT=All&Search=Search&VIEW=All&ORIENTATION=All&RESULTS=24 Prairie Falcon -- VIREO photo gallery]