Buteogallus anthracinuscommon black hawk(Also: common black-hawk)

Geographic Range

The Common Black-Hawk, Buteogallus anthracinus, is found in the Southwestern United States, through Mexico, Central America, and Northern South America to Guyana. They also can be found in Cuba and The Isle of Pines.( Snyder 1991; Clark and Wheeler 1987; Johnsgard 1990)

Habitat

Generally these birds inhabit lowland areas, with a source of water nearby where crabs, crayfish, or other aquatic foods are found. There are usually trees nearby for roosting and nesting. In Panama the birds are mainly found in coastal areas. They will range into the interior by following the course of a large river. In South and Central America the absence or presence of crabs may determine local presence of the species.

( Johnsgard 1990; Ridgely 1989; National Geographic 1999)

Physical Description

The Common Black-Hawk averages 53 centimeters in length (21 inches) and has a wingspan of 127 centimeters (50 inches).Like most other raptor species, Common Black-Hawks are sexually dimorphic, with the females being larger than the males.

Both sexes exhibit the same coloration. The head, body, and wing coverts are coal black. The under wing is black with the exception of a small white mark at the base of the outer two or three primaries. The black tail has one wide white band and a thin white terminal band. The iris color is dark brown. The cere (the fleshy covering at the top of the beak), legs and facial skin are a bright orangish yellow.

In contrast to the adults, the immature Black-Hawk is dark brown with buffy streaking. Coloration of the head and face includes a buffy line over the eye, a dark eye-line, a buffy cheek, and a dark vertical stripe running down the face. The immature Black-Hawk's iris color is medium brown.

(Clark and Wheeler 1987; National Geographic 1990; Johnsgard 1990 )
  • Range mass
    630 to 1300 g
    22.20 to 45.81 oz
  • Average mass
    950 g
    33.48 oz

Reproduction

The Black-Hawk breeding season runs from late February to late May. Copulation occurs about 15 to 90 meters from the nest on a branch or rock. The male may sweep down and land directly on the female, or he may perch beside her for a time before mounting. Up to four copulations per day occur as the egg laying period approaches. The nests of this species are usually built within 120 meters (480ft) of permanent flowing waters and is typically constructed 15 to 30 meters (60 to 120ft) above the ground. Occasionally nests have been found in rocky recesses. The clutch size is relatively small in this species, ranging from 1 to 3 eggs. The eggs have a granular surface,and the color of the eggs are grayish white with small specks and blotches. The eggs measure about 57x45 mm (2.5 X 1.5 inches). Incubation lasts for 38 to 39 days. Fledging period is between 43 to 50 days, and post-fledging dependence of the juvenile on the adult lasts 6 to 8 weeks.

(Johnsgard 1990; Ridgely 1989)
  • Average eggs per season
    1
    AnAge

Lifespan/Longevity

Behavior

No detailed information is available on pair bonding, territoriality, or most other aspects of this species' social behavior. The pair often fly together, with their wings fluttering and held at a strong dihedral angle. Loud and hoarse whistles, sounding like those of the Night-Heron are common during nesting season.

( Johnsgard 1990 )

Communication and Perception

Food Habits

The Black-Hawk primarily feeds on snakes, frogs, fishes, young birds, and land crabs. Sometimes the Black-Hawk supplements its diet with a variety of insects including grasshoppers and caterpillars. Reportedly, the Black-Hawks of Belize feed primarily on large land crabs.

( Johnsgard 1990, Ridgely 1989)

Economic Importance for Humans: Positive

Unknown

Conservation Status

Currently the North, Central, and South American populations of Black-Hawks seem to be self sustaining, but the species exibits a low reproduction rate. Conservation of the Black-Hawk depends on maintaining vital regions of riparian habitat, like Aravaipa Canyon Preserve in Arizona which is free of disturbance and development. It is considered threatened in Texas.

( Johnsgard 1990; Ridgely 1989; Texas Parks and Wildlife 2000)

Contributors

Jeremy Steinwand (author), Fresno City College, Carl Johansson (editor), Fresno City College.

Glossary

Nearctic

living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.

World Map

Neotropical

living in the southern part of the New World. In other words, Central and South America.

World Map

acoustic

uses sound to communicate

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

chemical

uses smells or other chemicals to communicate

endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

oviparous

reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.

rainforest

rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

tactile

uses touch to communicate

tropical savanna and grassland

A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.

savanna

A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.

temperate grassland

A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.

visual

uses sight to communicate

References

Baicich, J., J. Harrison. 1997. Eggs, Nests, and Nestlings of North American Birds. San Diego California: Academic Press.

Clark and Wheeler, 1987. A field guide to hawks. Boston Massachussets: Houghton Mifflin Company.

Johnsgard, P. 1990. Hawks, Eagles and Falcons of North America. Washington DC: Smithsonian Institution.

National Geographic Society, 1999. The Birds of North America. Washington DC: National Geographic Society.

Ridgely, R. 1989. A guide to the birds of Panama. Princton, NewJersey: Princton University Press.

Snyder, H., N. Snyder. 1991. Natural History and Conservation of North American Raptors. Stillwater, Mn: Voyageur Press Inc.

Texas Parks and Wildlife, 2000. "Index of Threatened and Endangered Bird Species of Texas" (On-line). Accessed 9/11/2000 at http://www.tpwd.state.tx.us/nature/endang/birds/.