BIOLOGICAL DATA AND HABITAT REQUIREMENTS
WILDLIFE SPECIES: Buteo jamaicensis | Red-Tailed Hawk 



TIMING OF MAJOR LIFE HISTORY EVENTS : 
Age at sexual maturity - Red-tailed hawks are generally sexually mature
at 2 years of age [38].

Breeding season - The breeding season generally occurs from late January
to September depending on geographic area [16,22,38,46].  Full clutches
may be expected as early as February in warmer parts of California and
in other states bordering Mexico and/or the Gulf coast.  For most of the
contiguous United States, clutches are laid in March.  In the northern
states and southern Canada, clutches are laid from March to early May.
In interior Alaska clutches are laid from April to late May [38].

Clutch size and incubation - Red-tailed hawks lay two to four eggs, with
three most common [16,22,38,46].  Clutch size may vary with prey
availability [38].  The eggs are incubated for 28 to 34 days [22,38].
If the first clutch is destoyed, red-tailed hawks may lay a replacement
clutch within 3 or 4 weeks [38].

Fledging - Nestlings fledge in 42 to 46 days [16,20,22,38].  Males
fledge earlier than females [38].  Fledglings continue to be fed by
parents and remain within the nesting territory for 30 days or more
after fledging [20].

Migration - Red-tailed hawks migrate as individuals.  Some established
breeders (especially in the southern United States) remain on or near
their territories all year.  Near Fairbanks, Alaska, a mature red-tailed
hawk spent three consecutive winters in the same territory [38].

Spring migration starts in February and March in northern Mexico and the
southern United States.  Early arrivals reach the northern states while
the ground is still under snow.  Along the Canadian border in the Great
Lakes region some red-tailed hawks are still migrating in late May and
June [38].  Western red-tailed hawks arrival in Yellowstone National
Park in the spring is probably dependent on the appearance of the ground
squirrels, which come out of hibernation about the first of April [52].

Fall migration from Canada and the adjoining northern states begins in
August and continues through early October.  Eastern red-tailed hawks
begin to migrate south from New England and other northern parts of
their range early in September [52].  Further south, red-tailed hawks
begin migrating from early October to mid-December [38].

Longevity - Red-tailed hawks have been reported to live up to 16 years
in the wild and 29 years in captivity [22].  The average longevity for a
red-tailed hawk that survives to maturity is 6 to 7 years [38].


PREFERRED HABITAT : 
Red-tailed hawks occupy a wide variety of open to semiopen habitats.
They generally avoid tundra and dense, unbroken woodland [1,9,25,13].
Open to semiopen coniferous, deciduous and mixed woodlands, woodland
edges, grasslands, parklands, rangelands, river bottomlands, and
agricultural fields with scattered trees are preferred.  Forest
clearings, alpine meadows, estuaries, and marshes are also commonly used
[6,8,22,34,39].  Hardwood draws surrounded by native prairie are
important habitats in the Great Plains [9].  In Wyoming and Montana,
red-tailed hawks nested in several habitats, but nests were most
numerous in riparian zones.  Upland draws with adjacent grassland or
agricultural tracts were also commonly used [51].

Nesting habitat - Red-tailed hawks usually nest in a tall tree in or at
the edge of woodlands, or in an isolated tree in an open area [1,9,13].
Red-tailed hawks frequently select the largest and tallest tree
available [1,13].  In treeless areas red-tailed hawks nest on rocky
cliffs or talus slopes, or in shrubs or cacti [13,28].  In the Sonoran
Desert, red-tailed hawks often nest in large saguaro (Carnegiea
gigantea) with projecting limbs [38].  Red-tailed hawks also nest on
artifical nest structures, the crossbars of utility poles, and towers
[25,38,44].  They sometimes add to an existing raven, crow (Corvus
spp.), gray squirrel (Sciurus spp.), or buteo (Buteo spp.) nest [38].
The nest is generally constructed next to the trunk of a tree in a
crotch or fork from 30 to 90 feet (9-27 m) above the ground [13,46].
Where tall trees are unavailable nests may be located almost on the
ground.  Red-tailed hawk nests are at most 6 feet (0.9 m) above the
ground in paloverde (Cercidium spp.) [38].  Nests are often reused from
year to year provided that the nests are not occupied by earlier nesting
raptors [20,51].  The mean distance between occupied nests in Wyoming
and Montana was 1.5 miles (2.4 km) [51].

Red-tailed hawks nest in a wide variety of tree species [8,43,44,45,51].
In central Missouri, 99 percent of red-tailed hawk nests were in
deciduous hardwoods.  Sycamore (Platanus occidentalis) was the most
frequently selected species (40%).  Other species included white
oak (Quercus alba), 32 percent; black oak (Q. velutina), 19.1 percent;
shingle oak (Q. imbricaria), 1.9 percent; eastern redcedar (Juniperus
virginiana), 1.9 percent; red oak (Q. rubra), 0.9 percent; American elm
(Ulmus americana), 0.9 percent; green ash (Fraxinus pennsylvanica), 0.9
percent; shagbark hickory (Carya ovata), 0.9 percent; mockernut hickory
(C. tomentosa), 0.9 percent; and eastern cottonwood (Populus
deltoides), 0.9 percent [45].

In Snohomish County, Washington, only black cottonwood (Populus
trichocarpa) and red alder (Alnus rubra) were utilized for nesting. No
nests were found in conifers [43].  In the highlands of southeastern New
York and northern New Jersey, red-tailed hawks built nests in 10
different species of trees, with the majority in oaks (82%) [44].  In
Wyoming and Montana, the majority (51%)of red-tailed hawk nests were
found in coniferous trees.  Forty-seven percent of the nests were found
in deciduous trees and 2 percent were located on cliffs [51].  In
British Columbia, coniferous trees (48%; 8 species) were used slightly
more that deciduous trees (44%; 4 species).  Black cottonwood (38%),
Douglas-fir (Pseudotsuga menziesii) (19%), and ponderosa pine (Pinus
ponderosa) (19%) were used most often [8].
 
Only 13 percent of the red-tailed hawk nests in a study area in
Wisconsin were located in closed-canopy woodlots.  Fifty-eight percent
of the nests were located in open groves, generally less than 1 acre
(0.4 ha) in size.  Twenty-nine percent were located in isolated trees
along fencelines and ditchbanks. The majority of the nest trees were on
well-drained upland sites [19].  Houston and Bechard [21] documented the
increase of nesting red-tailed hawks following the expansion of trees
into the prairie regions of Saskatchewan [44].

Foraging habitat - Red-tailed hawks generally forage in open habitats
containing lagomorphs, small rodents, and snakes.  During the nesting
season red-tailed hawks usually forage within 1.9 miles (3 km) of the
nest [25].  They are often observed hunting in clearcuts and
non-forested areas [35].  Red-tailed hawks usually search for prey from
elevated perches [20,23,38].  Consequently, they commonly occupy areas
that provide a relative abundance of potential perching sites [23].
James [23] found that 40 percent or more or the average red-tailed hawk
home range contained at least 10 perches per 40 acres (16.2 ha).  Snags
are commonly used for perches [12,14,31].  Red-tailed hawks in central
Iowa tend to select perches in groves of trees and along woodland edges
[53].  Foraging habitat in the Midwest is limited by large expanses of
cereal crops [9].

Winter habitat - Winter habitat for red-tailed hawks is generally the
same as the nesting habitat, except that high elevation areas are not
used [25].  Wintering red-tailed hawks in Illinois avoided plowed fields
and showed a preference for high perches in areas with groups of trees
or small woodlots [9].


COVER REQUIREMENTS : 
Red-tailed hawk nests are generally built on sites that provide a
commanding view of the area and unobstructed access to the nest.  Nests
are typically high in a tree that is taller than those surrounding it.
Some researchers have found that red-tailed hawk nests are often located
well up a slope or on a ridge or hilltop [38,44].  However, Speiser and
Bosakowski [44], reported that in the highlands of southeastern New york
and northern New Jersey red-tailed hawks most often nested between lower
and middle slopes, seldom near the top of a slope and never directly on
a ridgetop.  Red-tailed hawks seem to prefer trees with open crowns
[38].  Roost trees for raptors are usually large enough to provide
safety from any predatory threat from the ground.  They are typically
the largest trees in the stand; the crown near the top or the middle
portion of the tree is open and have stout lateral limbs with easy
access [50].  Red-tailed hawks are probably more efficient predators in
open areas than in areas with high vegetative cover.


FOOD HABITS : 
Red-tailed hawks are versatile, opportunistic predators [38].  Prey
items of red-tailed hawks are numerous.  Generally, any animal the size
of a jackrabbit (Lepus spp.) or smaller, including domestic animals, is
potential prey.  Red-tailed hawks primarily eat small mammals but also
eat birds, reptiles, and some insects [13,16,20,38].  In Wyoming,
Wisconsin, and Michigan, researchers found that mammals accounted for 93
percent, 85 percent, and 40 percent, respectively, of the prey species
taken [22].

Some prey items reported to be taken by red-tailed hawks include meadow
voles (Microtus pennsylvanicus), red-backed voles (Clethrionomys
gapperi), short-tail shrews (Blarina brevicauda), deer mice (Peromyscus
maniculatus), chipmunks (Tamias spp.), tree squirrels (Sciurus spp.),
ground squirrels (Citellus spp.), pikas (Ochotona princeps), prairie
dogs (Cynomys spp.), jackrabbits, cottontails (Sylvilagus spp.), skunks
(Mephitis spp. and Spilogale spp.), raccoons (Procyon lotor), woodchucks
(Marmota spp.), ring-necked pheasants (Phasianus colchicus), grouse, and
various songbirds [5,20,22,30,38].


PREDATORS : 
Information was not found in the literature regarding predation on
red-tailed hawks or their clutches.  However, species that kill other
raptors and destroy their clutches probably also kill  red-tailed
hawks.  Some raptor predators include great horned owls (Bubo
virginianus) and golden eagles (Aquila chrysaetos).  Other potential
predators include coyotes (Canis latrans), bobcats (Lynx rufus), skunks,
and crows.


MANAGEMENT CONSIDERATIONS : 
Unlike many other raptor species in North America, red-tailed hawk
populations have increased over much of their range due to fragmentation
of forests into small woodlots and increases in woodland edge [9].
Because of these habitat changes, red-tailed hawks have replaced
red-shouldered hawks (Buteo lineatus) throughout much of the
red-shoulderd hawks' former breeding range [41].  

To manage a stand for red-tailed hawks, 500 to 1,000 overstory trees per
acre (1,235-2,470/ha) with not more than 40 percent of the trees 8
inches (20 cm) d.b.h. is recommended [35].  Clearcutting is often
detrimental to the nest site but may be benefical to local populations
of red-tailed hawks by providing foraging habitat [35].  Snags and cull
trees should be retained as perch sites for red-tailed hawks [14,31,50].
Additionally, trees that contain nests should be retained whenever
possible.  Protecting habitat used by the prey base may also benefit
red-tailed hawks [50].  Although red-tailed hawks are tolerant of human
activities, construction of home sites degrades the quality of woodlands
by reducing habitat for some prey species [9].  In southeastern New York
and northern New Jersey, no red-tailed hawk nests were found near
high-density suburban housing developments [44].


REFERENCES : 
NO-ENTRY

Related categories for Wildlife Species: Buteo jamaicensis | Red-Tailed Hawk