Overview

Distribution

Range Description

Sagittarius serpentarius occurs in sub-Saharan Africa, from southern Mauritania, Senegal, The Gambia and northern Guinea eastwards, north of the forest zone, through southern Mali, Burkina Faso, Ghana, Togo, Benin, southern areas of Niger, Chad, Sudan, South Sudan and northern parts of Nigeria, Cameroon and the Central African Republic, to Ethiopia and north-western Somalia, and south through eastern areas of the Democratic Republic of Congo, Uganda, Kenya and Tanzania, to southern Africa, including Angola, Zambia, Malawi, Mozambique and South Africa. It is variably described as common to rare and localised, and is sedentary in some parts of its range and nomadic in others (Ferguson-Lees and Christie 2001). Ad-hoc records, localised surveys and anecdotal observations indicate an apparent decline in many parts of the species's range, with some of the strongest evidence suggesting rapid declines in Tanzania since the late 1990s and in South Africa between 1987-1991 and 2007-2010 (Baker et al. 2011).

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Range

Savanna and grasslands of Africa south of the Sahara.

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Sub-Saharan Africa: all S of Sahara except forest area and much of Somalia.

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Geographic Range

Sagittarius serpentarius is found throughout Africa south of the Sahara, except the extreme deserts of the Namib coast and the forested region around the equator in western Africa. Secretary birds do not occur in the southern areas of Guinea, Cote d'Ivoire, Ghana and Nigeria, and are entirely absent from the sub-Saharan countries of Sierra Leone and Liberia.

Biogeographic Regions: ethiopian (Native )

  • Mackworth-Praed, C., C. Grant. 1980. Birds of Eastern and North Eastern Africa, Volume 1. New York: Longman Inc..
  • Ferguson-Lees, J., D. Christie. 2001. Raptors of the World. New York: Houghton Mifflin Company.
  • Steyn, P. 1983. Birds of Prey of Southern Africa: Their Identification & Life Histories. Dover, New Hampshire: Tanager Books, Inc..
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Physical Description

Morphology

Physical Description

Secretary birds stand around 0.9 to 1.2 meters tall and weigh between 2.3 to 4.27 kg. Females tend to be slightly smaller than males. Wingspans of females range from 1.2 to 1.32 m, while those of males range between 1.26 to 1.35 m.

These large raptors have very distinctive morphology. The plumage is generally gray in color, perhaps with some white feathers. They have black flight feathers on the wings and a crest of black-tipped feathers on the back of the head. The bare face is orange to red in color. They have a relatively small head, a gray-white beak, a long neck, and an eagle-like body. Unlike an eagle, however, the bare, pinkish legs are very long and end in stubby toes with blunt claws. The tibial portions of the legs are covered in black plumage that give the bird the appearance that it is wearing shorts. The long tail has especially long central rectrices that are often tipped with black.

Juvenile Sagittarius serpentarius are similar in appearance to adults with a few exceptions. First, the bare skin on the face is yellow rather than orange or red. Second, juveniles show black coloration on the tips of the wing shoulder feathers, as well as brown to black barring on the underwing coverts. Lastly, juveniles also tend to have shorter central tail feathers and crests than adults.

It would be hard to confuse Sagittarius serpentarius with any other bird of prey, mainly due to their very long legs. From a distance secretary birds are mistaken for bustards or cranes. They are perhaps most commonly mistaken for blue cranes (Anthropoides paradiseus).

Range mass: 2300 to 4270 g.

Range wingspan: 1.2 to 1.35 m.

Other Physical Features: endothermic ; homoiothermic; bilateral symmetry

Sexual Dimorphism: male larger

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Ecology

Habitat

Habitat and Ecology

Habitat and Ecology
The species inhabits grasslands, ranging from open plains to lightly wooded savanna, but is also found in agricultural areas and sub-desert (Ferguson-Lees and Christie 2001). It ranges from sea-level to 3,000 m. A variety of prey is consumed, primarily insects and rodents, but also other mammals, lizards, snakes, eggs, young birds and amphibians. Breeding occurs throughout the year and the species typically nests in a flat-topped Acacia or other thorny tree, where it constructs a flattened stick structure (Ferguson-Lees and Christie 2001).


Systems
  • Terrestrial
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Steppe and savanna

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Secretary birds prefer open savannahs and grasslands, although they also live in semi-deserts and lightly wooded or scrub areas. In grasslands, secretary birds choose areas where the grass is one meter or less in height so their view is not obstructed. They are common near agricultural areas that offer hunting opportunities. Secretary birds are never found in true deserts with extreme aridity, or heavily wooded areas. These birds are found from sea-level to around 3,000 m.

Range elevation: 3,000 (high) m.

Habitat Regions: tropical ; terrestrial

Terrestrial Biomes: savanna or grassland ; scrub forest

Other Habitat Features: agricultural

  • Hosking, E., D. Hosking, J. Flegg. 1988. Birds of Prey of the World. Lexington, Massachusetts: The Stephen Greene Press.
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Dispersal

Movements and dispersal

Resident

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Trophic Strategy

Food Habits

Sagittarius serpentarius is an opportunistic predator with a broad prey base. The majority of the diet is made up of arthropods (including grasshoppers, beetles, spiders, scorpions, wasps, etc.) and small mammals (including mice, rats, hedgehogs, hares, mongooses, etc.). Other recorded prey of secretary birds includes small and young birds, eggs, amphibians, freshwater crabs, lizards, small tortoises, chameleons and snakes. Although this species is famed for killing and eating snakes, these reptiles are not eaten as often as is generally believed. However, the snakes taken as prey are often adders, cobras, and other venomous species.

Secretary birds hunt exclusively on the ground, either alone or in pairs (usually with their mate). The birds will set out across a grassy area at a steady pace searching for movement. If a particularly thick tuft of grass is encountered, the bird will stamp on it to flush out any potential prey. Once prey is spotted, the bird quickens its pace to take the prey by surprise. If a chase commences, the bird will flap its wings and run after the prey until catching up to it. With small prey, the bird will merely bend down and capture it in its bill. Larger prey, especially snakes, are stamped to death with the bird's blunt feet. A secretary bird will strike a snake just behind its head to snap its neck or stun it. Secretary birds are said to pick up a stunned snake, fly high into the air and drop the snake to its death, but this behavior has not been well documented. Once the prey is stunned or killed, the bird will swallow it whole through its large gape. If the prey proves too large, then the bird will tear it apart much like an eagle, using its feet to hold the prey down.

Secretary birds regurgitate pellets after the prey is digested. The pellets consist of fur, bones, and invertebrate exoskeletons. Sometimes grass is found in the pellets. It is unknown whether the birds swallow grass incidentally along with the prey, or if they swallow it intentionally to help hold the pellet together when there is little fur present. Stones, which are swallowed to help in breaking up the exoskeletons of larger invertebrates, have also been found in the pellets. Secretary bird pellets are found around and in the nest and are especially helpful to researchers in analyzing the diet of birds in that area.

Animal Foods: birds; mammals; amphibians; reptiles; eggs; insects; terrestrial non-insect arthropods; aquatic crustaceans

Primary Diet: carnivore (Eats terrestrial vertebrates, Insectivore )

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Associations

Ecosystem Roles

These birds prey on a wide range of large invertebrates and small to medium-sized vertebrates, but do not seem to have a great overall effect on these populations in the wild. Smaller, localized populations may be affected by predation from this species if hunting increases, especially during breeding season.

The vulnerable nestlings of secretary birds are occasionally taken as food by a number of predators. However, the low density of secretary bird nests means they are not vital to the predators' diets, and they have little effect on their survival.

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Predation

Secretary birds are generally only vulnerable to predation as eggs and young birds in the nest. Their large, open nests leave the nestlings vulnerable to predation by crows, ravens, ground hornbills and birds of prey, such as kites or eagle-owls.

Known Predators:

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Life History and Behavior

Behavior

Communication and Perception

Secretary birds are generally silent. When they do call, they typically give a deep, trisyllabic croaking wail that can be heard for quite some distance. This call, along with a drawn-out growling sound, is used in conjunction with aerial and ground displays during the courtship process. A softer version of the main call is used when feeding young. An occasional whistle is given from time to time. The young have their own calls to solicit food from their parents, which start off as a quiet squealing, then becoming a loud 'chok-a-chok-a-chok-a-chok'.

Communication Channels: visual ; acoustic

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Life Expectancy

Lifespan/Longevity

The lifespan of Sagittarius serpentarius is currently unknown and further study is required.

Average lifespan

Status: captivity:
18.6 years.

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Reproduction

Secretary birds are monogamous and are thought to pair for life. In courtship, they give a croaking call while displaying in the air and on the ground. Aerial displays consist of high soaring and diving performed by a single individual (usually the male), or by the pair when the male will dive toward the female and she will half-turn to present her claws. This courtship behavior is very similar to that of other birds of prey. On the ground, their displays are very crane-like with the two birds dancing around with their wings outstretched. Sometimes small groups of secretary birds will all join in this ground display behavior. After courtship displays, mating will usually take place on the ground, although some pairs mate in trees.

Mating System: monogamous

Sagittarius serpentarius may breed throughout the year, although there are peaks in breeding from August to March. Both the male and female will construct a large nest on a flat-topped tree (usually an acacia tree or some other thorny tree). The nest is usually a saucer-shaped platform made of sticks and lined with a thick layer of grass, wool, dung, and other such materials. A pair of secretary birds will usually reuse the same nest for many years, adding to the structure each year to create a nest that can range from 1.5 to 2.5 meters in diameter. A frequently reused nest will be abandoned if the structure becomes too large and heavy to be supported by the tree and seems likely to collapse.

The female lays a clutch of 1 to 3 eggs, with each egg laid two to three days apart. The eggs are chalky-white with reddish-brown streaks and are pyriform in shape. Eggs are variable in size and can range from 68 to 92 mm in length and 52 to 61 mm in width. Incubation of the eggs begins as soon as the first egg is laid. Incubation duties are shared by both the male and female, although more frequently by the female. The male brings food to the nest for the female during this time. In 42 to 46 days, the semi-altricial young hatch. Young generally hatch 2 to 3 days apart, but no siblicide has been observed. However, in a clutch of three eggs, the smallest chick usually dies of starvation because it cannot compete with its larger nest mates.

Hatchlings are covered in off-white down and have large heads that seem too heavy for their bodies. At two weeks of age, they attain a thick coat of gray down, and in three weeks the crest begins to appear. Development is slow in secretary birds and it takes six weeks before the hatchlings can stand on their own. At this stage, they learn to feed themselves from prey brought to the nest. By seven weeks, nestlings are fully feathered. Around 60 days, the young begin flexing their wings, often flapping and lifting small distances into the air before dropping back to the nest. In 64 to 106 days, the offspring will fledge. The offspring remain around the nest tree for an additional 62 to 105 days, during which time they are dependent upon the parents for food and training in foraging techniques.

Breeding interval: Secretary birds can raise two broods within ten months under desirable conditions.

Breeding season: Breeding can occur throughout the year.

Range eggs per season: 1 to 3.

Range time to hatching: 42 to 46 days.

Range fledging age: 64 to 106 days.

Range time to independence: 62 to 105 days.

Key Reproductive Features: year-round breeding ; gonochoric/gonochoristic/dioecious (sexes separate); fertilization

Both male and female secretary birds invest heavily in the young. Both sexes share incubation duties. After the eggs hatch, parental care is constant. Both the male and female feed the young via regurgitation, although the female mostly regurgitates food that the male has brought back to the nest for her. After about a month, parental care drops significantly, with the parents only returning to the nest to feed the chicks. After six weeks, the parents stop feeding via regurgitation and bring larger prey items that they give the chicks to eat directly. When the chicks fledge and leave the nest, the parents will teach the chicks how to hunt for prey. Once the offspring know how to provide for themselves and are independent, they generally head off on their own, leaving the parents’ territory. However, in some circumstances the parents will still tolerate having the juveniles in their territory and even allow the now-independent offspring to join in their hunts and share the nest tree as a roost. It is important to note that juveniles are not dependent on the parents during this time. They are just temporarily sharing a territory. Two months is the average amount of time that independent juveniles are allowed to remain in the parents’ territory before being chased away so that the parents can breed again.

Parental Investment: pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Male, Female); pre-weaning/fledging (Provisioning: Male, Female, Protecting: Male, Female); pre-independence (Provisioning: Male, Female, Protecting: Male, Female); post-independence association with parents; extended period of juvenile learning

  • Hosking, E., D. Hosking, J. Flegg. 1988. Birds of Prey of the World. Lexington, Massachusetts: The Stephen Greene Press.
  • Mackworth-Praed, C., C. Grant. 1980. Birds of Eastern and North Eastern Africa, Volume 1. New York: Longman Inc..
  • Ferguson-Lees, J., D. Christie. 2001. Raptors of the World. New York: Houghton Mifflin Company.
  • Steyn, P. 1983. Birds of Prey of Southern Africa: Their Identification & Life Histories. Dover, New Hampshire: Tanager Books, Inc..
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Molecular Biology and Genetics

Molecular Biology

Statistics of barcoding coverage: Sagittarius serpentarius

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 1
Specimens with Barcodes: 4
Species With Barcodes: 1
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Barcode data: Sagittarius serpentarius

The following is a representative barcode sequence, the centroid of all available sequences for this species.


There is 1 barcode sequence available from BOLD and GenBank.   Below is the sequence of the barcode region Cytochrome oxidase subunit 1 (COI or COX1) from a member of the species.  See the BOLD taxonomy browser for more complete information about this specimen.  Other sequences that do not yet meet barcode criteria may also be available.

GGAGCTGGTACAGGATGAACTGTGTACCCTCCACTAGCCGGAAACCTNGCCCATGCCGGAGCCTCAGTAGACCTAGCAATCTTCTCCCTACATCTAGCAGGTGTATCCTCAATTCTAGGTGCAATCAACTTTATTACAACTGCAATCAACATAAAACCTCCTGCTCTCTCACAATATCAAACCCCCCTGTTTGTATGATCCGTACTAATTACAGCCGTCTTACTCCTTCTCTCTCTCCCTGTCCTCGCTGCTGGCATTACCATATTACTAACAGATCGAAATCTAAACACCACATTCTTTGACCCAGCTGGAGGAGGCGACCCAGTCCTATACCNACACCTATTCTGATTCTTNGGTCATCNAGAAGTCTACATCCTNATTCTACCAGGCTTNGGAATCATTNNNCACGTAGTAGCATACTATGCGGGTAAAAAAGAACCTTNNGGTTATATAGGAATAGTATGAGCTATACTATCGATTGGATTCCTAGGCTTTATCGTATGAGCCCATCACATA
-- end --

Download FASTA File
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Conservation

Conservation Status

IUCN Red List Assessment


Red List Category
VU
Vulnerable

Red List Criteria
A4acd

Version
3.1

Year Assessed
2013

Assessor/s
BirdLife International

Reviewer/s
Butchart, S.

Contributor/s

Justification
This species is classified as Vulnerable because recent evidence from across its range suggests that its population is experiencing a rapid decline, probably owing to habitat degradation, disturbance, hunting and capture for trade.


History
  • 2012
    Vulnerable
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Sagittarius serpentarius is common throughout its range, although its numbers have been reduced in historic times. Since it is in no immediate danger, the IUCN Red List gives it a Lower Risk/Least Concern status. However, as human populations increase and more land is converted, there is likely to be a further reduction in secretary bird numbers. As a bird of prey in the order Falconiformes, Sagittarius serpentarius is protected under Appendix II of CITES, meaning that trade of this species is controlled.

US Migratory Bird Act: no special status

US Federal List: no special status

CITES: appendix ii

IUCN Red List of Threatened Species: least concern

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Population

Population
Although the species occurs across a vast range, surveyed densities suggest that the total population size does not exceed a five-figure number.

Population Trend
Decreasing
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Threats

Major Threats
Although the species may benefit from deforestation, such positive effects may be outweighed by the negative impacts of spreading cultivation and urbanisation (Ferguson-Lees and Christie 2001). The excessive burning of grasslands may suppress populations of prey species, whilst the intensive grazing of livestock is also probably degrading otherwise suitable habitat (Baker et al. 2011). Disturbance by humans, probably most often herders, is likely to negatively affect breeding. The species is captured and traded in apparently small numbers; however, it is unknown how many die in captivity and transit. Direct hunting and nest-raiding for other uses and indiscriminate poisoning at waterholes are also potential threats. These human-induced threats may compound the effects of severe droughts in some areas (Baker et al. 2011).

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Management

Conservation Actions

Conservation Actions
Conservation Actions Underway
CITES Appendix II. It occurs in a number of national parks and other protected areas across its large range.

Conservation Actions Proposed
Initiate a coordinated continent-wide monitoring programme to obtain an up-to-date population estimate and track the species's trends. In areas where the species is declining, raise awareness of threats amongst local people, particularly livestock herders. Monitor and tackle the capture and trade of the species.

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Relevance to Humans and Ecosystems

Benefits

Economic Importance for Humans: Negative

There are no known adverse effects of Sagittarius serpentarius on humans.

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Economic Importance for Humans: Positive

Perhaps the most beneficial action that Sagittarius serpentarius performs for humans is eating rodent and insect pests that feed on the crops of the local peoples. Secretary birds also hunt the snakes that are attracted to the fields to eat the rodents.

Positive Impacts: controls pest population

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Wikipedia

Secretarybird

Secretarybird at a zoo in Japan
Secretarybird at San Antonio Zoo in San Antonio, Texas

The secretarybird or secretary bird (Sagittarius serpentarius) is a very large, mostly terrestrial bird of prey. Endemic to Africa, it is usually found in the open grasslands and savannah of the sub-Saharan region. Although a member of the order Accipitriformes, which also includes many other diurnal raptors such as kites, buzzards, vultures, and harriers, it is given its own family, Sagittariidae.

It appears on the coats of arms of Sudan and South Africa.

Taxonomy[edit]

First described by English illustrator John Frederick Miller in 1779,[2] the secretarybird was soon assigned to its own genus, Sagittarius, by French naturalist Johann Hermann in his Tabula Affinatum Animalium.[3] It was not until 1935 that the species was moved to its own family, distinct from all other birds of prey—a classification confirmed by molecular systematics.[4] Recent cladistic analysis has shown Sagittariidae to be an older branch of the diurnal birds of prey than Accipitridae and Falconidae, but a younger divergence than Cathartidae.[5] Sometimes, the enigmatic bird Eremopezus is classified as an early relative of the secretarybird, though this is quite uncertain as the bird is only known from a few fragmentary body parts such as the legs. The earliest fossils associated with the family are two species from the genus Pelargopappus. The two species, from the Oligocene and Miocene respectively, were not discovered in Africa but France. The feet in these fossils are more like those of the Accipitridae; it is suggested that these characteristics are primitive features within the family. In spite of their age, it is not thought that the two species are ancestral to the secretarybird.[6]

Its common name is popularly thought to derive from the crest of long quill-like feathers, lending the bird the appearance of a secretary with quill pens tucked behind their ear, as was once common practice. A more recent hypothesis is that "secretary" is borrowed from a French corruption of the Arabic saqr-et-tair or "hunter-bird."[7]

The generic name "Sagittarius" is Latin for "archer," perhaps likening the secretarybird's "quills" to a quiver of arrows, and the specific epithet "serpentarius" recalls the bird's skill as a hunter of reptiles.[8] Alternatively, the name could refer to the last two constellations in the Zodiac, Sagittarius and Serpentarius (now known as Ophiuchus).[citation needed]

Biology[edit]

Description[edit]

The secretarybird has distinct black feathers protruding from behind its head

The secretarybird is instantly recognizable as having an eagle-like body on crane-like legs which increases the bird’s height to as much as 1.3 m (4 ft) tall. This bird has an eagle-like head with a hooked bill, but has rounded wings.[9] Body weight can range from 2.3 to 4.6 kg (5.1 to 10.1 lb) and height is 90–137 cm (35–54 in). Total length from 112 to 152 cm (44 to 60 in) and the wingspan is 191–220 cm (75–87 in).[10][11][12] The tarsus of the secretarybird averages 31 cm (12 in) and the tail is 57–85 cm (22–33 in), both of which factor into making them both taller and longer than any other species of raptor.[10] The neck is not especially long, and can only be lowered down to the inter-tarsal joint, so birds reaching down to the ground or drinking must stoop to do so.[7]

From a distance or in flight it resembles a crane more than a bird of prey. The tail has two elongated central feathers that extend beyond the feet during flight, as well as long flat plumage creating a posterior crest.[9] Secretarybird flight feathers and thighs are black, while most of the coverts are grey with some being white.[13] Sexes look similar to one another as the species exhibits very little sexual dimorphism, although the male has longer head plumes and tail feathers. Adults have a featherless red face as opposed to the yellow facial skin of the young.[9]

Habitat[edit]

Secretarybirds are endemic to Sub-Saharan Africa and are non-migratory, though they may follow food sources.[14] Their range extends from Mauritania to Somalia and south to the Cape of Good Hope.[9] These birds are also found at a variety of elevations, from the coastal plains to the highlands. Secretarybirds prefer open grasslands and savannas rather than forests and dense shrubbery which may impede their cursorial existence.[15] While the birds roost on the local Acacia trees at night, they spend much of the day on the ground, returning to roosting sites just before dark.[16]

Diet[edit]

Secretarybird seen in Serengeti National Park, Tanzania

Unlike most birds of prey, the secretarybird is largely terrestrial, hunting its prey on foot. Adults hunt in pairs and sometimes as loose familial flocks, stalking through the habitat with long strides.[17] Prey may consist of insects, mammals ranging in size from mice to hares and mongoose, crabs, lizards, snakes, tortoises, young birds, bird eggs, and sometimes dead animals killed in grass or bush fires. Larger herbivores are not generally hunted, although there are some reports of secretarybirds killing young gazelles.[17] The importance of snakes in the diet has been exaggerated in the past, although they can be locally important and venomous species such as adders and cobras are regularly among the types of snake preyed upon.[18]

In Namib-Naukluft National Park, Namibia

Prey is often discovered by the secretarybirds via stomping on clumps of vegetation, which then flushes prey for them to capture. It also waits near fires, eating anything it can that is trying to escape. They can either catch prey by chasing it and striking with the bill and swallowing (usually with small prey), or stamping on prey until it is rendered stunned or unconscious enough to swallow.[9] Studies of this latter strategy have helped reconstruct the possible feeding mechanisms employed by the gigantic 'terror birds' that lived between sixty and five million years ago.[19] Larger or dangerous prey, such as venomous snakes, are instead stunned or killed by the bird jumping onto their backs, at which point they will try to snap their necks or backs. There are some reports that, when capturing snakes, the secretarybirds will take flight with their prey and then drop them to their death, although this has not been verified. Even with larger prey, food is generally swallowed whole through the birds' considerable gape. Occasionally, like other raptors, they will tear apart prey with their feet before consuming it.[18]

Young are fed liquefied and regurgitated insects directly by the male or female parent and are eventually weaned to small mammals and reptile fragments regurgitated onto the nest itself. The above foodstuffs are originally stored in the crop of the adults.[9]

In hunting and feeding on small animals and arthropods on the ground and in tall grass or scrub, secretarybirds occupy an ecological niche similar to that occupied by peafowl in South and Southeast Asia, roadrunners in North and Central America and seriemas in South America.[citation needed]

Secretarybirds often use kicks to incapacitate and kill their prey, with the bird's sharp claws piercing the victim's body. Their kicks are incredibly powerful; they are capable of shattering a human's hand with a single kick.[20][21]

Reproduction[edit]

Mating[edit]

Flying overhead in Kenya

Secretarybirds associate in monogamous pairs. During courtship, they exhibit a nuptial display by soaring high with undulating flight patterns and calling with guttural croaking. Males and females can also perform a grounded display by chasing each other with their wings up and back, much like the way they chase prey. They usually mate on the ground, although some do so in Acacia trees. Secretarybirds will stay close to their mate even if their chick has already left.

Rearing[edit]

Nests are built at a height of 5–7 m (15–20 feet) on Acacia trees. Both the male and female visit the nest site for almost half a year before egg laying takes place. The nest is around 2.5 m (eight feet) wide and 30 cm (one foot) deep, and is constructed as a relatively flat basin of sticks.

Secretarybirds lay two to three oval, pale-green eggs over the course of two to three days, although the third egg is most often unfertilised.[citation needed] These eggs are incubated primarily by the female for 45 days until they hatch. The secretarybirds are facultatively fratricidal.[22] There are conflicting opinions on this phenomenon also called cainism—"No evidence [exist] of sibling aggression, but youngest in brood of 3 almost always dies of starvation..."[23]

The downy young can feed autonomously after 40 days, although the parents still feed the young after that time. Both the parents feed the young. At 60 days, the young start to flap their wings, and by day 65–80 are able to fledge. Fledging is accomplished by jumping out of the nest or using a semi-controlled fall via fervent wing flapping to the ground. After this time, the young are quickly taught how to hunt through expeditions with their parents and are considered independent soon after.[9]

Relationship with humans[edit]

Cultural significance[edit]

Flying at a bird conservation trust

The secretarybird has traditionally been admired in Africa for its striking appearance and ability to deal with pests and snakes. Africans sometimes call it the Devil's Horse. As such it has often not been disturbed, although this is changing as traditional observances have declined.[7]

The secretarybird is the national emblem of Sudan as well as a prominent feature on the Coat of arms of South Africa.

In Sudan, it is featured in the middle white strip of the Presidential Flag; it is the main object on the Presidential Seal, and features heavily in Sudanese military insignia. The secretarybird on the Presidential Flag and Seal has its head turned to the right, with its distinctive crest clearly visible and its wings spread out with a white banner between its outstretched wings reading "Victory is Ours".

The secretarybird has been a common motif for African countries on postage stamps, over 65 stamps from about 30 countries are known as of date including some from stamp-issuing entities such as Ajman, Manama. the Maldives and the United Nations where the bird does not occur.[24]

Threats[edit]

The young are preyed upon by crows, ravens, hornbills, large owls and kites as they are vulnerable in Acacia tree tops, with no known incidents of predation on adults.[9][18] As a population, the secretarybird is mainly threatened by loss of habitat and deforestation.[25] In 1968 the species became protected under the Africa Convention on the Conservation of Nature and Natural Resources.[9] Nevertheless the species is still widespread across Africa, and has adapted well to arable land where prey animals such as rodents are more common than in traditional habitat. The species is well represented in protected areas as well. They are assessed as endangered by the IUCN due to a recent rapid decline across their entire range.[1]

There is some anecdotal evidence that secretarybirds can be aggressive towards humans sometimes, and there are reports of them killing humans.[citation needed]

References[edit]

  1. ^ a b BirdLife International (2013). "Sagittarius serpentarius". IUCN Red List of Threatened Species. Version 2013.2. International Union for Conservation of Nature. Retrieved 26 November 2013. 
  2. ^ Miller, John Frederick (1779). Icones Animalium et Plantarum (in Latin). pt 5 pl. 28. 
  3. ^ Hermann, Johann (1783). Tabula affinitatum animalium olim academico specimine edita, nunc uberiore commentario illustrata cum annotationibus ad historiam naturalem animalium augendam facientibus (in Latin). Strasbourg: Argentorati. pp. 2, 370. 
  4. ^ Wink, Michael; Seibold, I.; Lotfikhah, F. & Bednarek, W. (1998): “Molecular systematics of holarctic raptors (Order Falconiformes)” in Chancellor, R.D., Meyburg, B.-U. & Ferrero, J.J. (eds.): Holarctic Birds of Prey: 29–48. Adenex & WWGBP. (PDF)
  5. ^ Mayr, G.; Clarke, J. (2003) "The deep divergences of neornithine birds: a phylogenetic analysis of morphological characters" Cladistics 19 527–553
  6. ^ Caley, Kevin (2007), "Fossil Birds", in del Hoyo, Josep; Elliott, Andrew; Christie, David, Handbook of the Birds of the World. Volume 12, Picathartes to Tits and Chickadees, Barcelona: Lynx Edicions, pp. 11–56, ISBN 84-96553-42-6 
  7. ^ a b c Kemp, AC (1994) Family Sagittariidae (Secretarybird) in del Hoyo, J.; Elliott A.; Sargatal J. (eds) Handbook of the Birds of the World, Volume 2 Barcelona:Lynx Edicions 206–215
  8. ^ Sherman, P.; Rasmussen P.. "Sagittarius serpentarius". Animal Diversity Web. University of Michigan. Retrieved 3 June 2009. 
  9. ^ a b c d e f g h i Eagles, Hawks, and Falcons of the World, Volume 2 - Brown, L. & Amadon, D. New York: McGraw-Hill Book Company (1968)
  10. ^ a b Raptors of the World - Ferguson-Lees, J.; Houghton Mifflin, New York. 978-0618127627 (2001)
  11. ^ [1] (2011).
  12. ^ Burnie D and Wilson DE (Eds.), Animal: The Definitive Visual Guide to the World's Wildlife. DK Adult (2005), ISBN 0789477645
  13. ^ Birds of Africa: South of the Sahara - Sinclair, I. & Ryan, P., Princeton and Oxford: Princeton University Press (2003)
  14. ^ Bird Migration in Africa: Movements between six continents, Volume 2 - Curry-Lindahl, K., New York: Academic Press (1981)
  15. ^ Sinclair, Ian; Hockey, Phil; Tarboton, Warwick (1993). Illustrated Guide to the Birds of Southern Africa. Princeton University Press. ISBN 0-691-09682-1. 
  16. ^ - Dean, W. R. J.; Milton, S.J.; Jeltsch, F. (1999) "Large trees, fertile islands, and birds in arid savanna" Journal of Arid Environments 41 61–78
  17. ^ a b The Depression of Reptile Biomass by Large Herbivores - Janzen, D.H., American Naturalist, 110, 71-400 (1976)
  18. ^ a b c [2] (2011).
  19. ^ Marshall, L.G. (March, 2001) "The Terror Birds of South America" Scientific American 82–89
  20. ^ The Uganda Society (1935). The Uganda Journal, Volume 3, Issue 1. 
  21. ^ Pitman, Charles Robert Senhouse (1938). A guide to the snakes of Uganda. The Uganda Society. 
  22. ^ Evolution of Growth Rates in Eagles: Sibling Competition Vs. Energy Considerations - Bortolotti, B.R., Ecology, 67, 182–194. (1986)
  23. ^ Hockey PAR, Dean, WRJ, Ryan PG (eds), 2005, Roberts - Birds of Southern Africa, VIIth ed. Cape Town: The Trustees of the John Voelcker Bird Book Fund. p543. ISBN 0-620-34053-3
  24. ^ Scharning, Kjell. "Secretary Bird Sagittarius serpentarius". Theme Birds on Stamps. Retrieved 6 June 2009. 
  25. ^ Allan, D.G.; Harrison, J.A.; Navarro, R.A.; van Wilgen, B.W.; Thompson, M.W.(1997) "The Impact of Commercial Afforestation on Bird Population in Mpumalanga Province, South Africa - Insights from Bird-Atlas Data" Biological Conservation 79 173–185
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