Falco rufigularisbat falcon

Geographic Range

The bat falcon, Falco rufigularis, is found in Mexico, Central and South America. It ranges from eastern Colombia east to the Guianas and Trinidad, and south to southern Brazil and northern Argentina (Weidensaul 1996; Del Hoyo et al. 1994).

Habitat

Bat falcons inhabit the tropical rain forests. Though they occur in unbroken forests, bat falcons seem to be able to adjust to human disturbance and are sometimes found to be more common in broken forest, which includes disturbed area, forest edge, road cuts, riverbanks, or cleared agricultural land with scattered trees.

Physical Description

Bat falcon adult males measure 24-29 cm (8-10 in.) in length with a wingspan of 56-58 cm (18-19 in.) females also range from 24-29 cm (8-10 in.) in length but have a larger wingspan, which ranges between 65 and 67 cm (21-22 in.) in length. The head and upper parts of their body are black, with grayish edging to contour the feathers from their upper back to tail coverts. Their throat and upper chest is white and tan extending to their neck. They have a long black tail with many fine white or gray stripes, and buff tip. The bat falcon has deep brown irises that may help camouflage while hunting at night. They also have small hooked beaks that allow the bat falcon to easily tear its meat. (Britannica 1999-00; Del Hoyo et al. 1994).

  • Range mass
    108 to 242 g
    3.81 to 8.53 oz
  • Average mass
    148 g
    5.22 oz

Reproduction

The bat falcon appears to have adapted to its habitat and nests in natural tree cavities or holes abandoned by parrots, in old trogon nests in termite colonies, or on cliffs, also on pre-Colombian ruins, and man made structures, such as sugar mill cranes. The bat falcon lays 2-4 eggs. Incubation periods last up to 4 to 7 weeks. Within 35-40 days of hatching it is fully feathered and able to eat whole prey on its own (Del Hoyo et al. 1994; Weidensaul 1996)

Behavior

Bat falcons are considered a solitary raptor. An important part of bat falcon's time is spent hunting. This type of behavior is a sign of their predator nature. Bat falcons primarily communicate through visual and vocal ways, often calling back and forth to their mate during breeding season. Courtship for the bat falcon begins in February or March, which is the middle of the dry season in Guatemala, Belize, and Mexico. In Trinidad, nesting begins in February, and in Colombia, breeding begins in February or March. In Venezuela, the bat falcon lays its eggs in March and in Guyana, in April. In Brazil, it will lay its eggs in August, the middle of dry season. Both parent will take an active role in protecting the nest, which may include chasing off other raptors. The male provides nearly all of the food during the nestling period. (Del Hoyo, Elliott, Sargatal 1994; Weidensaul 1996).

Communication and Perception

Food Habits

The bat falcon appears to have a preference for consuming bats, although they do not make up the majority of its diet. Their diet consists mainly of small birds and large insects, which include dragonflies (Odonata), moths (Lepidoptera), large grasshoppers (Orthopera), Homoptera, and Hymenoptera. The diet of the bat falcon varies by seasons and is divided into summer and winter diets. This shift in diet is affected by the change in the most abundant and nutritious prey obtainable. The summer diet consists of mostly birds and during winter, mostly insects. The bat falcon hunts during periods of dusk to dawn and is considered nocturnal (Weidensaul 1996; Del Hoyo et al. 1994).

Economic Importance for Humans: Positive

none

Economic Importance for Humans: Negative

none

Conservation Status

This species is not globally threatened. Falco rufigularis tolerates and can even benefit from patchy, small scale deforestation. The bat falcon has stopped breeding in areas of South America where the forest has significantly changed to agriculture. This type of behavior is likely to recur in other places throughout the range (del Hoyo et al. 1994).

Contributors

Mark Pacheco (author), Fresno City College, Carl Johansson (editor), Fresno City College.

Glossary

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

visual

uses sight to communicate

References

Del Hoyo, J., A. Elliott, J. Sargatal. 1994. Handbook of the birds of the World. Vol 2 New World Vultures to Guineafowl. Barcelona: Lynx Edicions.

Encyclopedia Britannica, 1999. Accessed July,9 2000 at http://www.britannica.com.

Weidensaul, S. 1996. Raptors: Birds of prey. New York, NY: Lyons & Burford.