Geographic Range
Harpy eagles (
Harpia harpyja
) are distributed throughout Central to South America. They are found from southern
Mexico to the eastern part of Bolivia, southern Brazil, and northern Argentina.
- Biogeographic Regions
- neotropical
Habitat
Harpy eagles live in the canopies of tropical lowland rainforests. They prefer undisturbed
forests but will also hunt along open patches of land. They generally are found in
mid to upper levels of rain forest canopies where they are able to find preferred
prey.
- Habitat Regions
- tropical
- terrestrial
- Terrestrial Biomes
- rainforest
Physical Description
Harpy eagles are the largest species of eagle with a body length that can range from
89 to 102 cm and a wing span of 2 m. Their talons can be up to 12.5 cm long. Females
are normally larger with an average weight of 7 to 9 kg, while the males weigh an
average of 5 to 8 kg. The mantle, scapulars, the top of the secondaries and primaries,
secondary coverts, greater primary coverts, and the rump are slate black in color,
but can vary to gray. The tail is made up of long gray feathers with horizontal black
bars. The breast, belly, and flanks, are light grey with horizontal black stripes.
The head, thighs and vent are light gray and the nape has a dark band across it. The
crown of harpy eagles consists of long black feathers which raise when threatened,
though some theorize they also raise them to direct sound to their ears. Their bills
are black and their feet are yellow with black talons.
- Other Physical Features
- endothermic
- homoiothermic
- bilateral symmetry
- Sexual Dimorphism
- sexes alike
- female larger
Reproduction
Harpy eagles form breeding pairs that last for life. The pair builds the nest together
and chirp to each other while doing so. They will occasionally rub their bills together
for a few seconds before going back to work. This activity seems to help them to preserve
their bond. They build their nests in large, tall trees, high above the forest floor.
During the nest building phase, the pair will rarely radiate more than 180 m from
the nest. The mating pair of harpy eagles does not have a courtship display before
mating, and will mate multiple times over a period of a few days.
- Mating System
- monogamous
The breeding season for harpy eagles coincides with the start of the rainy season
which usually begins in April or May. Harpy eagles construct large nests that measure
1.2 m thick and 1.5 m across. The nests are built 27 to 43 m above ground, and consist
of woven sticks lined with soft vegetation and animal fur. These impressive nests
are reused by breeding pairs every year. The female lays two eggs, but will raise
only one chick. Eggs are incubated for an average of 56 days. Both parents tend the
chick for 10 months, well after the chick fledges between 6 and 7 months of age.
Juveniles often stay near their parents for some time and will occasionally beg for
food. Juveniles do not reach maturity until 5 or 6 years old, at which time they
often return to their original nesting area to breed. Pairs of harpy eagles only
breed once every 2 to 3 years.
- Key Reproductive Features
- iteroparous
- seasonal breeding
- gonochoric/gonochoristic/dioecious (sexes separate)
- sexual
- fertilization
- oviparous
Harpy eagles invest a lot of time and energy into their offspring. Both parents incubate
the egg for the 56 day incubation period. The female will perform most of the incubation
while the male is in search of food. Chicks are hatched altricial, and thus are helpless
with downy feathers and eyes open. They will only tend a single chick, so if two eggs
are laid, the first born will be fed and the second will perish from starvation.
The parents actively tend the young for 10 months, which is several months after the
chick fledges at 6 or 7 months old. The parents feed the juvenile once every few days
and during this time the juvenile is mostly inactive while occasionally making small
flights within the nesting tree. Juvenile harpy eagles often remain in the parents'
territory for at least 1 year.
- Parental Investment
- altricial
- male parental care
- female parental care
-
pre-fertilization
- provisioning
-
protecting
- female
-
pre-hatching/birth
-
provisioning
- male
- female
-
protecting
- male
- female
-
provisioning
-
pre-weaning/fledging
-
provisioning
- male
- female
-
protecting
- male
- female
-
provisioning
-
pre-independence
-
provisioning
- male
- female
-
protecting
- male
- female
-
provisioning
- post-independence association with parents
- extended period of juvenile learning
Lifespan/Longevity
Harpy eagles are estimated to live 25 to 35 years if they remain healthy. Disease
and injury dramatically affects their chances of survival by inhibiting their ability
to find and capture prey.
Behavior
Harpy eagles are most often found in pairs as they form monogamous pairs that mate
for life. Pairs are also observed with a third, juvenile eagle which is their offspring
from the most recent breeding season. They are solitary hunters which use their keen
sense of sight to locate arboreal prey in thick rainforests. Harpy eagles can potentially
perch for up to 23 hours in search of prey. They are incredibly skilled in flight
and are adept at maneuvering through their dense, forest habitat. They are diurnal
and hunt during the day.
- Key Behaviors
- arboreal
- flies
- glides
- diurnal
- motile
- sedentary
- territorial
Home Range
Harpy eagles require territories of about 30 square km for adequate hunting. They
are very territorial and will drive out any competing individuals.
Communication and Perception
Harpy eagles use vocalizations to communicate with one another and visual displays
and vocalizations in mating rituals. They will often produce vocalizations while sitting
on perches, which sound like "uahaaaau...uahaaaau...uahaaaau". This is believed to
be territorial behavior. Pairs of harpy eagles will often rub their bills together,
which is believed to be part of mate bonding. Like all birds, harpy eagles perceive
their environment through visual, tactile, auditory and chemical stimuli.
- Other Communication Modes
- duets
Food Habits
Harpy eagles depend on their 5 inch long talons and powerful legs to subdue prey items.
They are well-adapted to snatching prey from the canopy and are powerful enough fliers
to carry their prey away to a perch to feed. Harpy eagles' main food sources are sloths
and primates, but have also been known to prey upon lizards, birds, small rodents,
and sometimes small deer.
- Primary Diet
-
carnivore
- eats terrestrial vertebrates
- Animal Foods
- birds
- mammals
- reptiles
Predation
Harpy eagles are apex predators of their rainforest ecosystems. Hatchling harpy eagles
may be at risk from predation by other harpy eagles. This type of predation is a
rare occasion as the parents defend the nest and their territory.
Ecosystem Roles
Harpy eagles are apex predators of their rainforest ecosystems. Like most predators,
they aid in keeping prey populations in check. They have an important role in controlling
mesopredators such as capuchin monkeys (
Cebus
).
Capuchin monkeys
often prey on bird eggs, and if left unchecked these mesopredators could lead to
the local extintions of sensitive species.
Economic Importance for Humans: Positive
Harpy eagles will occasionally be used in ceremonial rituals by indigenous hunters.
Harpy eagles are also the national birds of both Panama and Parana, Brazil.
Economic Importance for Humans: Negative
There have been reports of harpy eagles preying on small livestock, such as chickens,
of local farmers. However, this is a rare occurrence and the eagles overall have
no adverse effects on humans.
Conservation Status
Harpy eagles are listed as least concern by the IUCN Red List but notes the population
is declining. They are listed as endangered by the United States Federal List in
isolated regions of Mexico. The international trade of this species is regulated under
CITES which considers harpy eagles to be under the greatest threat of becoming endangered.
There have been many cases of local extinctions in areas with a lot of human activity.
This is caused mainly to the destruction of its habitat due to logging and farming.
There have also been reports of harpy eagles being shot by farmers who perceive the
eagles as livestock predators. Programs are being set up to educate farmers and hunters
to increase awareness and understanding of harpy eagles.
Additional Links
Contributors
Kyle Shaner (author), Northern Michigan University, Alec Lindsay (editor), Northern Michigan University, Rachelle Sterling (editor), Special Projects.
- Neotropical
-
living in the southern part of the New World. In other words, Central and South America.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- tropical
-
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
- terrestrial
-
Living on the ground.
- 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.
- 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.
- 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.
- monogamous
-
Having one mate at a time.
- 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).
- seasonal breeding
-
breeding is confined to a particular season
- sexual
-
reproduction that includes combining the genetic contribution of two individuals, a male and a female
- fertilization
-
union of egg and spermatozoan
- oviparous
-
reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.
- altricial
-
young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.
- male parental care
-
parental care is carried out by males
- female parental care
-
parental care is carried out by females
- arboreal
-
Referring to an animal that lives in trees; tree-climbing.
- diurnal
-
- active during the day, 2. lasting for one day.
- motile
-
having the capacity to move from one place to another.
- sedentary
-
remains in the same area
- territorial
-
defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement
- visual
-
uses sight to communicate
- tactile
-
uses touch to communicate
- acoustic
-
uses sound to communicate
- duets
-
to jointly display, usually with sounds in a highly coordinated fashion, at the same time as one other individual of the same species, often a mate
- carnivore
-
an animal that mainly eats meat
- visual
-
uses sight to communicate
- tactile
-
uses touch to communicate
- acoustic
-
uses sound to communicate
- chemical
-
uses smells or other chemicals to communicate
References
Beacham, W. 2000. Beacham’s Guide to the Endangered Species of North America . Osprey, FL: Beacham Publishing Corporation.
Fowler, J., J. Cope. 1964. Noted on the Harpy Eagle in New Guiana. The Auk: a Quarterly Journal of Ornithology , 81/3: pg 257-273.
Frost, P. 2007. Birds of Prey . Bath BA1 1HE, UK: Parragon Publishing.
Grzimek, B. 2003. Grzimek’s Animal Life Encyclopedia . N/A: Gacl.
Merrick, P. 2006. Eagles . Mankato, MN: The Childs World.
Rettig, N., K. Hayes. 1995. Remote world of the harpy eagle. National Geographic , 187.n2: pp 40- 49.
Rettig, N. 1978. Breeding Behavior of the Harpy Eagle. The Auk: A Quarterly Journal of Ornithology , 95/4: pg. 629- 643.
Tingay, R. 2010. The Eagle Watchers: Observing and Conserving Raptors Around the World . Ithaca, NY: Cornell University Press.
Trinca, C., S. Ferrari, A. Lees. 2008. Curiosity killed the bird: arbitrary hunting of Harpy Eagles Harpia harpyja on an agricultural frontierin southern Brazilian Amazonia. Cotinga , 30: pg 12-15.
de Carvalho, jr., O., M. Galetti. 2000. Sloths in the Diet of a Harpy Eagle Nestling in Eastern Amazon. The Wilson Bulletin , 112/ 4: pg. 535-536.