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Accipiter cooperii

(Big Blue Darter)

Overview

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Interesting Facts

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Common Names

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Click on the language to view common names.

Common Names in Dutch:

Coopers sperwer

Common Names in English:

Big Blue Darter, Chicken Hawk, Cooper's Hawk, Hen Hawk, Mexican hawk, quail hawk, striker, swift hawk

Common Names in French:

epervier de Cooper

Common Names in German:

Rundschwanzsperber

Common Names in Japanese:

クーパーハイタカ

Common Names in Spanish:

Gavil, Gavilán de Cooper

Description

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Physical Description

Adult : Head : dark gray or black on top Crown: usually blackish, distinctly darker than back Ear Tufts: deep red to yellow Face : Cere: yellow Eye Color: red Facial Skin : yellow Bill: black with gray base Body: Belly: reddish bars Breast: reddish bars Underparts: more finely barred, on average, than Sharp-Shinned Hawk Legs : Leg Color: yellow Tail: dark bars and a white band on tip Shape : rounded.Immature: Head: dark gray or black on top Crown: usually blackish, distinctly darker than back Ear Tufts: deep red to yellow Face: Cere: yellow Eye Color: red Facial Skin: yellow Bill: black with gray base Body: Belly: reddish bars Breast: reddish bars Underparts: more finely streaked than immature Sharp-Shinned Hawk Legs: Leg Color: yellow Tail: dark bars and a white band on tip Shape: rounded.

Color:

Adults have a dark gray to black crown; black back and wings ; dark and light banding on the tail; thick white band at the tip of the tail; reddish barring on the white chest and belly; white undertail coverts. Immatures have variable brown streaking throughout the body; dark and light banding on the tail.

Adult: Red eye · Black cap · Blue-gray back and upperwings · White breast, belly and underwing coverts marked by fine, thin, reddish bars · White undertail coverts · Tail, blue gray above and pale below, barred with black bands · Flight feathers, blue-gray above and pale below, with dark bars

Immature: Yellow eye · Brown head with indistinct pale supercilium · Brown cap, nape, back, and upperwings · White underparts marked by thin black streaks, concentrated on chest · Tail, brown above and pale below, barred with dark bands · White terminal band

Size/Age/Growth

About 14 to 21 inches long, with a wingspan of 27 to 36 inches. Adults weigh about 12.3 ounces .

Habitat

In the Southeast, non-breeding habitat use is similar to breeding habitat use.

The Cooper’s hawk breeds primarily in riparian areas and oak woodlands and apparently is most common in montane canyons (Garrett and Dunn 1981; Hamilton and Willick 1996). It frequents landscapes where wooded areas occur in patches and groves and often uses patchy woodlands and edges with snags for perching (Beebe 1974). Dense stands with moderate crown-depths are usually used for nesting (Zeiner, et al. 1990). Migrant and wintering birds are generally more catholic in their choice of habitats and may be found with regularity in developed (e.g. , suburban) areas. They hunt in broken woodland and habitat edges, catching predominantly avian prey in air , on the ground , and in vegetation. This species is seldom found in areas without dense tree stands or patchy woodland habitat (Zeiner, et al. 1990). Within the range in California, it most frequently uses dense stands of live oak, riparian deciduous, or other forest habitats near water (Zeiner, et al. 1990). The Cooper’s hawk tends to nest in stands with lower densities of taller and larger trees and a greater proportion of hardwood cover than conifer species when compared to other accipiters (Trexel, et al. 1999).

The Cooper’s hawk apparently reduces the niche overlap with the northern goshawk by using areas with greater shrub cover, flatter terrain, and locations that are closer to roads, forest openings, and human habitation (Bosakowski, et al. 1992).

The Cooper’s hawk is tolerant of human disturbance and habitat fragmentation and breeds in suburban and urban settings (Murphy, et al. 1988). The urban sites have included isolated trees in residential neighborhoods with commercial and recreational activities less than 150 meters distant and houses 20 to 30 meters distant. Typically, there is some forest edge habitat included within their home range even if nesting within an urban setting and this forest edge may serve as the primary hunting site (Rosenfield and Bielefeldt 1993).

Vegetation: tropical deciduous forests, gallery forests, tropical lowland evergreen forest, pine-oak forests • Minimum Elevation: 600 meters • Maximum Elevation: 3,000 meters • Foraging Strata: Canopy • Center of Abundance: Upper subtropical: higher slopes, 500-1,600 m.; subtropics. • Sensitivity to Disturbance: Medium

Typically found at an altitude of 0 to 3,787 meters (0 to 12,425 feet).[1]

Ecology: List of Habitats :

Biology

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Diet

Avian prey items, especially passerines , comprise 70 percent of the number of food items and 58 percent of the dietary biomass delivered to Cooper’s hawk broods at two nests surrounded by a mixed grass prairie with mammalian prey making up the remainder (Peterson and Murphy 1992). In general, during breeding and non-breeding, the species uses avian prey predominantly, sometimes taking fish and mammals (Terres 1980). In comparison to the northern goshawk, the Cooper’s hawk takes more avian prey (Bosakowski, et al. 1992; Whaley and White, 1994). The Cooper’s hawk catches small birds, especially young birds during the nesting season , and small mammals; it also takes reptiles and amphibians .

The Cooper’s hawk hunts in broken woodland and habitat edges ; it catches prey in the air , on the ground , and in vegetation. Sometimes it runs prey down in dense thickets. It uses cover to hide, attack, and approach prey; ut also soars and makes low, gliding search flights (Zeiner, et al. 1990). It forages by dashing through the woods in a low, swift flight, around trees , through the brush and reaches out in the air or on the ground to catch avian prey with the talons (Terres 1980). After catching its prey, the Cooper’s hawk may fly with the prey to a water source in order to drown it (Terres 1980).

Reproduction

The Cooper’s hawk breeds primarily in riparian areas and oak woodlands and apparently is most common in montane canyons (Garrett and Dunn 1981; Hamilton and Willick 1996). It usually nests in second-growth conifer stands, or in deciduous riparian areas, usually near streams . Nesting and foraging usually occur near open water or riparian vegetation (Zeiner, et al. 1990). Throughout much of the west, the Cooper’s hawk nests in stands of cottonwoods along stream courses especially where the tree stands are fairly large (Call 1978). Denser stands of trees with moderate crown-depth are used for nesting. It appears that the vertical structure of the nest site tree is more important to the nest-site selection than the horizontal structure (Wiggers and Kritz 1991).

A study comparing nesting habits of Cooper’s hawk and sharp-shinned hawk, found that Cooper’s hawks “tend to nest in stands with lower densities of taller and larger trees with a greater proportion of hardwood cover” (Trexel, et al. 1999). It apparently does not tolerate nesting sharp-shinned hawks in the vicinity of its nest (Terres 1980).

In urban settings in Tucson, Arizona, Cooper’s hawks have been found nesting mainly in eucalyptus (70.8%), aleppo pine (25.0%) and cottonwood trees (4.2%) (Boal, et al. 1998). Nest trees were found to be taller and of greater diameter than randomly sampled trees and thus had more canopy cover and the nest trees were often the largest tree in the nest site. Although nest sites were always in heavily forested areas, they were significantly closer to forest openings and wetland, were usually on level ground and were never located on a ridgeline or steep upper slope (Bosakowski, et al. 1992a).

It locates its nest on a horizontal limb of a pine or hardwood, near the trunk or in the crotch of a hardwood tree species, usually 10 to 60 feet above the ground and sometimes uses an old nest of a crow (Harrison 1978). It also often nests just below the lowest live limbs (Zeiner, et al. 1990). The nest is typically a platform of sticks and twigs lined with bark (Call 1978). Cooper’s hawk eggs are laid in February through June and the clutch size is 3 to 6; usually 4 to 5 (Brown and Amadon 1968). Eggs are incubated mostly by the female for approximately 24 days (Terres 1980). In rural Wisconsin, Rosenfield, et al. (1995) found a minimum intergeneration turnover time of six years for breeding Cooper’s hawks.

Dispersal : Although it is mostly a year-long resident, some Cooper’s hawks from more northern areas, migrate into California. The Cooper’s hawk may also move downslope and south from areas of heavy snow and return to the general nesting area in the spring (Zeiner, et al. 1990). The mean distance from the natal site to the breeding site is 12 kilometers for males and 14.4 kilometers for females. Adult birds frequently reoccupy nesting areas and breeding site fidelity is assumed (Rosenfield and Bielefeldt 1993). The Cooper’s hawk may reuse the same nest site for multiple years (Call 1978).

The breeding season begins in early April and extends until late May. Breeding habitat is usually deciduous or conifer woods with nearby water. The nest is commonly in a tree about 35 - 45 feet ( m ) above the ground. The male and female build a platform-style nest near the trunk of the tree out of sticks and twigs and line it with wood chips, bark strips, and down . The female lays 3 - 6 (usually 4 - 5) eggs that she incubates for 32 - 36 days. The male usually feeds the incubating female. The young are semi-altricial and fledge 27-34 days after hatching . The female provides most of the care for the young at the nest. The male young usually fledge sooner than their female siblings. The young birds return to the nest for about 10 days after fledging to be fed. They become independent of the adults at about 8 weeks after they hatch .

Migration

Some migrate

Behavior

The species is a year-long, diurnally active bird (Zeiner, et al. 1990).

Survival: One banded individual was recorded as being shot at 7 years 5 months old (Terres 1980). The maximum reported age is 12 years (Rosenfield and Bielefeldt 1993). The yearly fledgling success is about 2 young/ pair with nesting success of 57 percent to 93 percent (Craighead and Craighead 1956; Rosenfield and Bielefeldt 1993). Mortality rates have been estimated as 72 percent to 78 percent in the first year, 34 percent to 37 percent thereafter (Rosenfield and Bielefeldt 1993).

Socio-Spatial Behavior: Nest sites within stands of oaks are located approximately 1.6 miles apart and thus are distributed widely but sparsely within woodland habitat (Zeiner, et al. 1990). The seasonal home range size has been estimated at 784 hectares with the daily home range averaging 231 hectares (Murphy, et al. 1988). Cooper’s hawks may require a minimum of 15 acres of suitable, undisturbed timber for nesting (Call 1978). Rosenfield, et al. (1995) found a nesting density of 331 ha/pair in a long-term study in rural Wisconsin. Studies of urban areas have reported a maximum density of 272 ha/pair, according to this same study. In Michigan, Craighead and Craighead (1956) measured four home ranges that averaged 311 ha (768 ac) and varied from 96-401 ha (237-992 ac); they estimated that 17 other home ranges averaged 207 ha (512 ac), and varied from 18-531 ha (45-1312 ac). They reported one home range in Wyoming of 205 ha (506 ac). Males defend an area about 100 m (330 ft ) around potential nest sites prior to pair formation (Brown and Amadon 1968). Nests in Oregon were 3.2 to 4.2 km (2 to 2.6 mi ) apart (Jackman and Scott 1975). Elsewhere, nests have been reported 1.6 to 2.4 km (1 to 1.5 mi) apart (Meng 1951, Brown and Amadon 1968). Of 77 territories in California, in oak stands, mean distance between nests was 2.6 km (1.6 mi) (Zeiner, et al. 1990).

Taxonomy

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Synonyms

Accipiter cooperi • Accipiter cooperii (Bonaparte, 1828)

Notes

Name Status: Accepted Name .

Last scrutiny: 17-Oct-2001

Similar Species

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Sharp-Shinned Hawk

Members of the genus Accipiter

ZipcodeZoo has pages for 86 species and subspecies in this genus:

A. albogularis (Pied Goshawk) · A. albogularis albogularis (Pied Goshawk) · A. badius (Little Banded Goshawk) · A. badius badius (Little Banded Goshawk) · A. bicolor (Bicoloured Sparrow Hawk) · A. bicolor bicolor (Bicoloured Sparrow Hawk) · A. brachyurus (New Britain Collared Sparrow Hawk) · A. brevipes (Levant Sparrow Hawk) · A. buergersi (Chestnut-Shouldered Goshawk) · A. butleri (Nicobar Sparrowhawk) · A. butleri butleri (Nicobar Sparrowhawk) · A. castanilius (Chestnut-Bellied Sparrow Hawk) · A. chionogaster (White-Breasted Hawk) · A. cirrhocephalus (Australian Collared Sparrow Hawk) · A. cirrhocephalus cirrhocephalus (Australian Collared Sparrow Hawk) · A. cirrocephalus (Australian Collared Sparrow Hawk) · A. cirrocephalus cirrocephalus (Australian Collared Sparrow Hawk) · A. collaris (Semi-Collared Sparrow Hawk) · A. cooperi (Big Blue Darter) · A. cooperii (Big Blue Darter) · A. erythrauchen (Grey Moluccan Collared Sparrow Hawk) · A. erythronemius (Rufous Thighed Hawk) · A. erythropus (Western Little Sparrowhawk) · A. erythropus erythropus (Red-Thighed Sparrow Hawk) · A. fasciatus (Christmas Island Nighthawk) · A. fasciatus fasciatus (Australian Goshawk) · A. fasciatus natalis (Christmas Island Nighthawk) · A. francesiae (Frances' Sparrow Hawk) · A. francesii (Anjouan Island Sparrow Hawk) · A. francesii francesii (Frances' Sparrow Hawk) · A. francesii pusillus (Anjouan Island Sparrow Hawk) · A. gentilis (Eurasian Goshawk) · A. gentilis apache (Apache Northern Goshawk) · A. gentilis atricapillus (Northern Goshawk) · A. gentilis gallinarum (Northern Goshawk) · A. gentilis gentilis (Northern Goshawk) · A. gentilis laingi (Northern Goshawk) · A. griseiceps (Sulawesi Crested Goshawk) · A. gularis (Japanese Lesser Sparrow Hawk) · A. gularis gularis (Japanese Lesser Sparrow Hawk) · A. gundlachi (Gundlach's Hawk) · A. gundlachii (Gundlach's Hawk) · A. gundlachi gundlachi (Gundlach's Hawk) · A. haplochrous (New-Caledonia Sparrow Hawk) · A. henicogrammus (Moluccan Goshawk) · A. henstii (Henst's Goshawk) · A. imitator (Imitator Sparrow Hawk) · A. luteoschistaceus (Slaty-Backed Goshawk) · A. madagascariensis (Madagascar Sparrow Hawk) · A. melanochlamys (Black Mantled Goshawk) · A. melanoleucus (Black Sparrow Hawk) · A. melanoleucus melanoleucus (Great Sparrow Hawk) · A. meyerianus (Meyer's Goshawk) · A. minullus (African Little Sparrow Hawk) · A. minullus minullus (African Little Sparrow Hawk) · A. nanus (Celebes Little Sparrow Hawk) · A. nisus (Northern Sparrow Hawk) · A. nisus nisus (Northern Sparrow Hawk) · A. novaehollandiae (White Goshawk) · A. novaehollandiae novaehollandiae (White Goshawk) · A. ovampensis (Ovampo Sparrow Hawk) · A. poliocephalus (New Guinea Grey-Headed Goshawk) · A. poliogaster (Gray-Bellied Hawk) · A. princeps (New Britain Grey-Headed Goshawk) · A. radiatus (Doria's Goshawk) · A. rhodogaster (Vinous-Breasted Sparrow Hawk) · A. rhodogaster rhodogaster (Vinous-Breasted Sparrow Hawk) · A. rufitorques (Fiji Goshawk) · A. rufiventris (Red-Breasted Sparrowhawk) · A. rufiventris rufiventris (Rufous-Breasted Sparrow Hawk) · A. soloensis (Chinese Sparrowhawk) · A. striatus (Slate-Colored Hawk) · A. striatus perobscurus (Sharp-Shinned Hawk) · A. striatus striatus (Sharp-Shinned Hawk) · A. striatus suttoni (Sharp-Shinned Hawk) · A. striatus velox (Sharp-Shinned Hawk) · A. superciliosus (Tiny Sparrow Hawk) · A. tachiro (African Goshawk) · A. tachiro tachiro (African Goshawk) · A. toussenelii (Red-Chested Goshawk) · A. trinotatus (Spot-Tailed Sparrow Hawk) · A. trivirgatus (Asian Crested Goshawk) · A. trivirgatus trivirgatus (Asian Crested Goshawk) · A. ventralis (Plain-Breasted Hawk) · A. virgatus (Bersa Sparrow Hawk) · A. virgatus virgatus (Besra Sparrow Hawk)

More Info

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Further Reading

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Notes

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Contributors

Data Sources

Accessed through GBIF Data Portal November 27, 2007:

Identifiers

Footnotes

  1. Mean = 1,266.590 meters (4,155.479 feet), Standard Deviation = 1,411.780 based on 3,608 observations. Altitude information for each observation from British Oceanographic Data Centre. [back]
Last Revised: 7/14/2012