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+#REDIRECT [[Secretary bird]]
-{{For|the fictional character created by Victor Mollo|Secretary Bird (bridge player)}}
-{{speciesbox
-| name = Secretarybird
-| status = VU
-| status_system = IUCN3.1
-| status_ref = <ref name=IUCN>{{cite iucn|url=https://www.iucnredlist.org/details/22696221/0 |title=''Sagittarius serpentarius'' |author=BirdLife International |author-link=BirdLife International |year=2013 |accessdate=26 November 2013|ref=harv}}</ref>
-| image = Sagittarius serpentarius Sekretär.JPG
-| image_caption = In [[Serengeti National Park]]
-| grandparent_authority =[[Otto Finsch|Finsch]] & [[Gustav Hartlaub|Hartlaub]], 1870<ref>{{ cite book | last1=Finsch | first1=Otto | author1-link=Otto Finsch | last2=Hartlaub | first2=Gustav | author2-link=Gustav Hartlaub | year=1870 | title=Die Vogel Ost-Africas: Baron Carl Claus von Deer Decken's Reisen in Ost-Africa | language=German | location=Leipzig | publisher=C. F. Winter | page=93 | url=https://biodiversitylibrary.org/page/13999696 }}</ref><ref>{{cite book | last=Bock | first=Walter J. | year=1994 | title=History and Nomenclature of Avian Family-Group Names | series=Bulletin of the American Museum of Natural History | volume= Number 222 | publisher=American Museum of Natural History | place=New York | pages=112, 133. 236 | hdl=2246/830 }}<!--Linked page allows download of the 48MB pdf--></ref>
-| parent_authority = [[Johann Hermann|Hermann]], 1783
-| genus = Sagittarius
-| species = serpentarius
-| authority = ([[John Frederick Miller|J. F. Miller]], 1779)
-| range_map = Sekretär Verbreitungsgebiet.png
-}}
+{{Redirect category shell|1=
-The '''secretarybird''' or '''secretary bird''' (''Sagittarius serpentarius'') is a large, mostly terrestrial [[bird of prey]]. [[Endemic (ecology)|Endemic]] to [[Africa]], it is usually found in the open grasslands and savannah of the [[Sub-Saharan Africa|sub-Saharan region]]. [[John Frederick Miller]] described the species in 1779. Although a member of the order [[Accipitriformes]], which also includes many other [[Diurnal animal|diurnal]] [[Bird of prey|raptors]] such as [[kite (bird)|kites]], [[hawk]]s, [[vulture]]s, and [[harrier (bird)|harriers]], it is placed in its own family, [[Sagittariidae]]. The secretarybird is instantly recognizable as a very large bird with an eagle-like body on [[crane (bird)|crane-like]] legs which increases the bird's height to as much as {{convert|1.3|m|ft|abbr=on}} tall. Adults have a featherless red-orange face and predominantly grey plumage, with a flattened dark crest and black [[flight feather]]s and thighs.
+{{R from other capitalisation}}
-Breeding can take place at any time of year, but tends to be late in the dry season. The nest is built in a thorny tree, and a clutch of one to three eggs is laid. All three young can survive to fledging in years with plentiful food. The secretarybird hunts and catches prey on the ground, often stomping on victims to kill them. Rodents and grasshoppers likely form the bulk of its diet, though it does kill snakes. It appears on the [[Coat of arms|coats of arms]] of [[Emblem of Sudan|Sudan]] and [[Coat of arms of South Africa|South Africa]].
-== Taxonomy ==
-{{Cladogram
-|caption=Position of the secretarybird in the order [[Accipitriformes]].<ref name=hackett2008/><ref name=ioc/>
-|align=right
-|cladogram={{Cladex| style=font-size:80%;line-height:75%;width:340px;
-|1={{clade
-   |1=[[Cathartidae]] – New World vultures (7 species)
-   |2={{clade
-      |1=[[Sagittariidae]] – '''Secretarybird'''
-      |2={{clade
-         |1={{clade
-            |1=[[Pandionidae]] – Ospreys (2 species)
-            |2=[[Accipitridae]] – Kites, hawks and eagles (256 species)
-            }}
-         }}
-      }}
-   }}
-  }}
 }}
-The Dutch naturalist [[Arnout Vosmaer]] described the secretarybird in 1769 based on a live specimen that had been sent to Holland from the [[Cape of Good Hope]] two years earlier by an official of the [[Dutch East India Company]]. Vosmaer suggested that the species was called "Sagittarius" because its gait was thought to resemble an archer's. He also mentioned that it was known as the "Secretarius" by farmers who had domesticated the bird to combat pests around their homesteads and proposed that the word "Secretarius" might be a corruption of "Sagittarius".<ref>{{ cite book | last=Vosmaer | first=Arnout | year=1769 | title=Description d'un oiseau de proie, nommé le sagittaire, tout-à-fait inconnu jusque'ici; apporté du Cap de Bonne Espérance | language=French | location=Amsterdam | publisher=Pierre Meyer | url=https://biodiversitylibrary.org/page/51569536 }} Contains eight pages and a plate.</ref><ref>{{ cite book | last=Vosmaer | first=Arnout | year=1769 | title=Beschryving van eenen Afrikaanschen nog geheel onbekenden roof-vogel de Sagitarrius genaamd op de Kaap de Goede Hoop | language=Dutch | location=Amsterdam | publisher=Pierre Meyer | url=https://biodiversitylibrary.org/page/27738512 }} Contains eight pages and a plate.</ref>
-In 1779 the English illustrator [[John Frederick Miller]] included a coloured plate of the secretarybird in his ''Icones Animalium et Plantarum'' and coined the [[binomial name]] ''Falco serpentarius''.<ref>{{cite book |last=Miller|first=John Frederick| author-link=John Frederick Miller | year=1779 | title=Icones Animalium et Plantarum |volume=1|at=pt 5 pl. 28|language=Latin | location=London | url=https://biodiversitylibrary.org/page/49649826 }}<!--This is a very rare book. See Walters M. (2009) The identity of the birds depicted in Shaw and Miller's Cimelia physica. Archives of Natural History. Volume 36, Page 316-326 DOI 10.3366/E0260954109001016 --></ref> It was assigned to its own genus ''Sagittarius'' in 1783 by the French naturalist [[Johann Hermann]] in his ''Tabula Affinitatum Animalium''.<ref>{{cite book | last=Hermann | first=Johann | author-link=Johann Hermann | year=1783 | title=Tabula affinitatum animalium | location= Argentorati [Strasbourg] | publisher=Printed by Joh. Georgii Treuttel | language=Latin | pages=136, 235 | url=https://biodiversitylibrary.org/page/39000807 }}</ref> The generic name ''Sagittarius'' is Latin for "archer", and the [[specific epithet]] ''serpentarius'' is from Latin ''serpens'' meaning "serpent" or "snake".<ref>{{cite book | last=Jobling | first=James A. | year=2010| title=The Helm Dictionary of Scientific Bird Names | publisher=Christopher Helm | location=London | isbn=978-1-4081-2501-4 | pages=345, 354 }}</ref> In spite of its large range, the secretarybird is considered as [[monotypic]]: no [[subspecies]] are recognised.<ref name=ioc>{{cite web| editor1-last=Gill | editor1-first=Frank | editor1-link=Frank Gill (ornithologist) | editor2-last=Donsker | editor2-first=David | year=2019 | title=Hoatzin, New World vultures, Secretarybird, raptors | work=IOC World Bird List Version 9.2 | url=https://www.worldbirdnames.org/bow/raptors/ | publisher=International Ornithologists' Union | accessdate=21 November 2019 }}</ref>
-The evolutionary relationship of the secretarybird to other raptors had long puzzled ornithologists. The species was usually placed in its own family [[Sagittariidae]] within the order [[Falconiformes]].<ref>{{ cite book | editor1-last=Mayr | editor1-first=Ernst | editor1-link=Ernst Mayr | editor2-last=Cottrell | editor2-first=G. William | year=1979 | title=Check-list of Birds of the World | volume=Volume 1 | edition=2nd | publisher=Museum of Comparative Zoology | place=Cambridge, Massachusetts | page=390 | url=https://biodiversitylibrary.org/page/16109030 }}</ref>  A large [[molecular phylogenetic]] study published in 2008 found that the secretarybird was [[Sister group|sister]] to a [[clade]] containing the ospreys in the family [[Pandionidae]] and the kites, hawks and eagles in the family [[Accipitridae]]. The same study found that the falcons in the order Falconiformes were only distantly related to the other diurnal birds of prey. The families [[Cathartidae]], Sagittariidae, Pandionidae and Accipitridae were therefore moved from Falconiformes to the resurrected [[Accipitriformes]].<ref name=hackett2008>{{ cite journal | last1=Hackett | first1=S.J.| last2=Kimball | first2=R.T. | last3=Reddy | first3=S. | last4=Bowie | first4=R.C.K.| last5=Braun | first5=E.L.| last6=Braun | first6=M.J.| last7=Chojnowski | first7=J.L.| last8=Cox | first8=W.A. | last9=Han | first9=K-L. | last10=Harshman | first10=J. | last11=Huddleston | first11=C.J.| last12=Marks | first12=B.D.| last13=Miglia | first13=K.J.| last14=Moore | first14=W.S.| last15=Sheldon | first15=F.H.| last16=Steadman | first16=D.W.| last17=Witt | first17=C.C.| last18= Yuri | first18= T. | year=2008 | title=A phylogenomic study of birds reveals their evolutionary history | journal=Science | volume=320 | issue=5884 | pages=1763–1767 | doi=10.1126/science.1157704 | pmid=18583609| bibcode=2008Sci...320.1763H}}</ref>{{efn|Some ornithologists place the family Cathartidae in a separate order [[Cathartiformes]].<ref>{{cite journal| last1=Chesser | first1=R. Terry  | last2=Burns | first2=Kevin J. | last3=Cicero | first3=Carla | last4=Dunn | first4=John L.  | last5=Kratter | first5=Andrew W | last6=Lovette | first6=Irby J | last7=Rasmussen | first7=Pamela C. | last8=Remsen | first8=J.V. Jr | last9=Rising  | first9=James D. | last10=Stotz | first10=Douglas F. | last11=Winker  | first11=Kevin | year=2017 | title=Fifty-seventh supplement to the American Ornithological Society's ''Check-list of North American Birds'' |journal=The Auk |volume=133 | issue=3 |pages=544–560 |doi=10.1642/AUK-16-77.1 | doi-access=free }}</ref>}} A later molecular phylogenetic study published in 2015 confirmed these relationships.<ref>{{ cite journal | last1=Prum | first1=R.O. | author1-link=Richard Prum | last2=Berv | first2=J.S. | last3=Dornburg | first3=A. | last4=Field | first4=D.J. | last5=Townsend | first5=J.P. | last6=Lemmon | first6=E.M. | last7=Lemmon | first7=A.R. | year=2015 | title=A comprehensive phylogeny of birds (Aves) using targeted next-generation DNA sequencing | journal=Nature | volume=526 | issue= 7574| pages=569–573 | doi=10.1038/nature15697 | pmid=26444237 | bibcode=2015Natur.526..569P }}</ref>
-Sometimes, the enigmatic bird ''[[Eremopezus]]'' is classified as an early relative of the secretarybird, though this is uncertain as the bird is only known from a few fragmentary body parts such as the legs. The earliest [[fossil]]s 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.<ref name="HBW">{{Citation | first = Kevin | last = Caley |  editor-first = Josep | editor-last = del Hoyo | editor2-first = Andrew | editor2-last = Elliott | editor3-first = David | editor3-last = Christie | contribution = Fossil Birds | title = Handbook of the Birds of the World. Volume 12, Picathartes to Tits and Chickadees | year = 2007 | pages = 11–56| place = Barcelona | publisher = Lynx Edicions | isbn = 978-84-96553-42-2 | title-link = Handbook of the Birds of the World }}</ref> Though strongly convergent with the modern secretarybird, the extinct raptor ''[[Apatosagittarius]]'' is thought to be an [[accipitrid]].<ref>Apatosagittarius terrenus Feduccia & Voorhies, 1989</ref>
-"Secretarybird"  has been designated as the official common name for the species by the [[International Ornithologists' Union]] (IOC).<ref name=ioc/> The French polymath [[Georges-Louis Leclerc, Comte de Buffon]] suggested that the name secretary/secrétaire had been chosen because of the long quill-like feathers at the top of the bird's neck.<ref>{{ cite book | last=Buffon | first=Georges-Louis Leclerc de | author-link=Georges-Louis Leclerc, Comte de Buffon | year=1780 | title=Histoire Naturelle des Oiseaux | volume=Volume 14 | place=Paris | publisher=De l'Imprimerie Royale | pages=30–39 [35] | chapter=Le Secrétaire ou Le Messager| language=French | chapter-url=https://biodiversitylibrary.org/page/42337677 }}</ref> More recently it has been suggested that "secretary" is from the French "secrétaire", a corruption of the Arabic ''saqr-et-tair'' meaning either "hawk of the semi-desert" or "hawk that flies".<ref>{{ cite journal | last=Fry | first=C.H. | year=1977 | title=Etymology of "Secretary Bird" | journal=Ibis | volume=119 | issue=4 | page=550 | doi=10.1111/j.1474-919X.1977.tb02069.x }}</ref> Professor Ian Glenn has dismissed this etymology on the grounds that there is no evidence that the name came through French. Instead, Buffon's etymology is almost certainly correct and the word comes from the Dutch "Secretarius" for "secretary" used by the settlers in South Africa. Glenn further suggests Vosmaer's "Sagittarius" is a misheard or mis-transcribed form of "Secretarius", rather than the other way around as proposed by Vosmaer.<ref>{{ cite journal | last=Glenn | first=Ian | year=2018 | title=Shoot the messager? How the secretarybird ''Sagittarius serpentarius'' got its names mostly wrong | journal=Ostrich | volume=89 | issue=3 | pages=287–290 | doi=10.2989/00306525.2018.1499561 }}</ref>
-The [[Maasai people]] call it ''Ol-enbai nabo'' "one arrow", referring to its crest feathers.<ref>{{cite journal |last1=Galaty |first1=John G. |title=The Maasai Ornithorium: Tropic Flights of Avian Imagination in Africa |journal=Ethnology |date=1998 |volume=37 |issue=3 |pages=227–238 |doi=10.2307/3774014|jstor=3774014 }}</ref>
-== Description ==
-[[File:Secretary Bird with open beak.jpg|thumb|left|The secretarybird has distinct black feathers protruding from behind its head.]]
-The secretarybird is instantly recognizable as a very large bird with an eagle-like body on [[crane (bird)|crane-like]] legs, which increase the bird's height to as much as {{convert|1.3|m|ft|abbr=on}} tall. This [[bird]] has an [[eagle|eagle-like]] head with a hooked [[beak|bill]], but has rounded wings.<ref name="four">{{ cite book | last1=Brown | first1=L. | last2=Amadon | first2=D. | year=1968 | title=Eagles, Hawks, and Falcons of the World | volume=Volume 2 | location=New York | publisher=McGraw-Hill }}</ref> Height can range from {{convert|90|to|137|cm|in|abbr=on}}. Total length from {{convert|112|to|152|cm|in|abbr=on}} and the wingspan is {{convert|191|-|220|cm|in|abbr=on}}.<ref name="Ferguson-Lees">{{ cite book | last1=Ferguson-Lees | first1=J. | year=2001 | title=Raptors of the World | location=New York | publisher=Houghton Mifflin | isbn=978-0618127627}}</ref> Body mass can range from {{convert|2.3|to|5|kg|lb|abbr=on}} with 20 birds from southern Africa found to weigh an average of {{convert|4.02|kg|lb|abbr=on}}.<ref name="CRC">{{ cite book | editor-last=Dunning | editor-first=John B. | year=2008 | title=CRC Handbook of Avian Body Masses | edition=2nd |  location=Boca Raton, Florida | publisher=CRC Press | isbn=978-1-4200-6444-5}}</ref> Other attempts to estimate the mean weight range for secretarybirds correspondingly lie between {{convert|3.5|and|4.2|kg|lb|abbr=on}}.<ref>{{cite journal | last1 = Maloiy | first1=G.M.O. | last2=Alexander | first2=R.M. | last3=Njau | first3=R. | last4=Jayes | first4=A.S. | year=1979 | title =Allometry of the legs of running birds | doi = 10.1111/j.1469-7998.1979.tb03940.x | journal = Journal of Zoology | volume = 187 | issue = 2| pages = 161–167 }}</ref><ref>{{ cite journal | last=Kinzelbach | first=R.K. | year=2008 | title=Pre-Linnaean pictures of the secretarybird, ''Sagittarius serpentarius'' (JF Miller, 1779) | journal=Archives of Natural History | volume=35 | issue=2 | pages=243–251 | doi=10.3366/E0260954108000375 | url=https://www.researchgate.net/publication/250230337 }}</ref> The tarsus of the secretarybird averages {{convert|31|cm|in|abbr=on}} and the tail is {{convert|57|-|85|cm|in|abbr=on}}, both factor into making them both taller and longer than any other species of [[Accipitriformes|raptor]] since these features are not as long in any other living raptor.<ref name="Ferguson-Lees" /> 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.<ref name =dehoyo>Kemp, Alan C. (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</ref>
-From a distance or in flight it resembles a [[crane (bird)|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.<ref name="four" />  The plumage of the crown, upperparts, and lesser and median wing coverts are blue-grey, and the underparts and underwing coverts are lighter grey to grey-white. The scapulars, primary and secondary [[flight feather]]s, rump and thighs are black, while the uppertail coverts are white, though barred with black in some individuals.<ref name=brown1982/> It has a large wedge-shaped tail with alternating white and black banding at its ends. Sexes look similar to one another as the species exhibits very little [[sexual dimorphism]], although the male has longer head plumes and tail feathers,<ref name="four" /> and tends to have paler plumage.  Adults have a featherless red-orange face with pale brown irises and a blue-grey cere. The legs are pinkish grey.<ref name=brown1982/>
-Immature birds have yellow bare skin on their faces, more brownish plumage, shorter tail feathers and greyish irises.<ref name=brown1982/>
-== Distribution and habitat ==
-[[File:Secretary bird skeleton.jpg|thumb|right|Skeleton]]
-The secretarybird is endemic to [[Sub-Saharan Africa]] and is [[bird migration|non-migratory]], though it may follow food sources.<ref name="Curry">{{ cite book | last1=Curry-Lindahl | first1=K. | year=1981 | title=Bird Migration in Africa: Movements between Six Continents | volume=Volume 2 | location=New York | publisher=Academic Press | isbn=978-0-12-200102-4 }}</ref> Its range extends from [[Mauritania]] to [[Somalia]] and south to the [[Cape of Good Hope]].<ref name="four" /> The species is also found at a variety of [[elevation]]s, from the [[coastal plain]]s to the highlands. The secretarybird prefers open [[grassland]]s, [[savanna]]s and [[shrubland]] ([[Karoo]]) rather than [[forest]]s and dense [[shrubbery]] which may impede its [[cursorial]] existence.<ref name="Sinclair01">{{cite book |last1=Sinclair |first1=Ian |last2=Hockey |first2=Phil |last3=Tarboton |first3=Warwick |year=1993 |title=Illustrated Guide to the Birds of Southern Africa  | publisher=Princeton University Press |isbn=978-0-691-09682-7}}</ref> More specifically, it prioritises areas with grass under 0.5 m high and avoids those with grass over 1 m high. It is rarer in grasslands in northern parts of its range that otherwise appear similar to areas in southern Africa where it is abundant, suggesting it may avoid hotter regions. It also avoids deserts.<ref name=brown1982/>
-== Behaviour and ecology ==
-Secretarybirds generally [[Bird#Resting and roosting|roost]] in trees of the genus ''[[Acacia]]'' or ''[[Balanites]]'', or even introduced pine trees in South Africa. They set off 1–2 hours after dawn. Mated pairs roost together but may forage separately, though often remain in sight of one another. They pace around at a speed of 2.5–3&nbsp;km/hour, taking 120 steps on average each minute.<ref name=brown1982/> After spending much of the day on the ground, secretarybirds return at dusk,<ref name="Dean">{{ cite journal | last1=Dean | first1=W.R.J. | last2=Milton | first2=S.J. | last3=Jeltsch | first3=F.  | year=1999 | title=Large trees, fertile islands, and birds in arid savanna | journal=Journal of Arid Environments | volume=41 | issue=1 | pages=61–78 | doi=10.1006/jare.1998.0455 | bibcode=1999JArEn..41...61D }}</ref> moving [[Windward and leeward|downwind]] before flying in upwind.<ref name=brown1982/>
-=== Breeding ===
-[[File:20170525 Pairi Daiza Sagittarius serpentarius con huevos.jpg|upright|thumb|left|Captive secretarybird with two eggs in its nest.]]
-Secretarybirds form monogamous pairs and defend a large territory of around {{cvt|50|km2}}. They can breed at any time of the year, more frequently in the late dry season. 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 defend their territory. They either mate on the ground or in trees.<ref name=brown1982>{{ cite book | editor1-last=Brown | editor1-first=L.H. | editor2-last=Urban | editor2-first=E.K. | editor3-last=Newman | editor3-first=K. | year=1982 | title=The Birds of Africa | volume=Volume 1 | location=London | publisher=Academic Press | isbn=978-0-12-137301-6 | pages=437–440 }}</ref><!--p. 439-->
-The nest is built by both sexes in a dense thorny tree, often an ''Acacia'', at a height of between {{convert|2.5|and|13|m|ft|sigfig=1}} above the ground. The nest is constructed as a relatively flat platform of sticks {{convert|1.0|-|1.5|m|ft|sigfig=1}} across with a depth {{convert|30|-|50|cm|in|sigfig=2}}. The shallow depression is lined with grass and the occasional piece of dung.<ref name=brown1982/>
-Eggs are laid at two to three day intervals until the clutch of 2-3 eggs is complete. The elongated chalky bluish green or white eggs average {{cvt|78|x|57|mm}} and weigh {{cvt|130|g}}.<ref name=brown1982/> Both parents incubate the eggs starting as soon as the first egg is laid but it is usually the female that remains on the nest overnight. The incubating parent greets its partner when it returns with a display of bowing and bobbing its head with neck extended. The tail is held upright and its feathers fanned out,and the chest feathers are puffed out.<ref name=kemp1995>{{ cite journal | last=Kemp | first=Alan C. | year=1995 | title=Aspects of the breeding biology and behaviour of the secretarybird ''Sagittarius serpentarius'' near Pretoria, South Africa | journal=Ostrich | volume=66 | issue=2–3 | pages=61–68 | doi=10.1080/00306525.1995.9633760 }}</ref> The eggs hatch after around 45 days at intervals of 2–3 days.<ref name=brown1982/> Both parents feed the young. The adults regurgitate food onto the floor of the nest and then pick up items and pass them to the chicks.<ref name=kemp1995/> Despite the difference in nestling size due to the asynchronous hatching, little sibling aggression has been observed.<ref name=brown1982/> Under favourable conditions all chicks from a clutch of 3 eggs fledge,<ref>{{ cite journal | last1=Herholdt | first1=J.J. | last2=Anderson | first2=M.D. | year=2006 | title=Observations on the population and breeding status of the African whitebacked vulture, the black-chested snake eagle, and the secretarybird in the Kgalagadi Transfrontier Park | journal=Ostrich | volume=77 | issue=3&4 | pages=127–135 | doi=10.2989/00306520609485523 }}</ref> but if food is scarce one or more of the chick will die from starvation.<ref name=brown1982/>
-The young are born covered in grey-white [[Down feather|down]] that becomes darker grey after two weeks. Their bare facial skin and legs  are yellow. Crest feathers appear at 21 days, and flight feathers by 28 days. They can stand up and feed autonomously after 40 days, although the parents still feed the nestlings after that time. At 60 days, the now fully -feathered young start to flap their wings. Their weight gain over this period is variable, from {{cvt|56|g}} at hatching, to {{cvt|500|g}} at 20 days, {{cvt|1.1|kg}} at 30 days, {{cvt|1.7|kg}} at 40 days, {{cvt|2|kg}} at 50 days, {{cvt|2.5|kg}} at 60 days, and {{cvt|3|kg}} at 70 days. The age at which they leave the nest is very variable but is usually around 75–80 days but can be anywhere between 65 and 106 days. Fledging is accomplished by jumping out of the nest or using a semi-controlled glide to the ground.<ref name=brown1982/> After this time, the young are quickly taught how to hunt through expeditions with their parents and are considered independent soon after.<ref name="four" />
-Juveniles remain in their natal range before dispersing when they are between four and seven months of age.<ref name=whitecross2019>{{ cite journal | last1=Whitecross | first1=M.A. | last2=Retief | first2=E.F. | last3=Smit-Robinson | first3=H.A. | year=2019 | title=Dispersal dynamics of juvenile secretarybirds ''Sagittarius serpentarius'' in southern Africa | journal=Ostrich | volume=90 | issue=2 | pages=97–110 | doi=10.2989/00306525.2019.1581295 }}</ref> The usual age at which they first breed is uncertain but there is a record of a male bird breeding successfully at an age of 2 years and 9 months. This is young for a large raptor.<ref name=whitecross2019/>
-==== In captivity ====
-The first successful rearing of a secretarybird in captivity occurred in 1986 at the Oklahoma City Zoo. Although secretarybirds build their nests in the trees in the wild, the captive birds at the Oklahoma City Zoo built theirs on the ground, which left their eggs open to depredation by local wild mammals. Therefore, zoo staff removed the eggs from the nest each time they were laid to be incubated and hatched at a safer location.<ref>{{cite journal|last=Todd|first=William T.|title=Hand-rearing the secretary bird ''Sagitarius serpentarius'' at Oklahoma City Zoo|journal=International Zoo Yearbook |volume=27 | issue=1| year=1988| pages=258–263| doi=10.1111/j.1748-1090.1988.tb03220.x}}</ref> The species now successfully breeds in captivity around the world, including in the San Diego Zoo.<ref>{{Cite web|url=http://animals.sandiegozoo.org/animals/secretary-bird|title=Secretary Bird {{!}} San Diego Zoo Animals & Plants|website=animals.sandiegozoo.org|language=en|access-date=2017-11-18|url-status=live|archiveurl=https://web.archive.org/web/20141119184114/http://animals.sandiegozoo.org/animals/secretary-bird|archivedate=19 November 2014|df=dmy-all}}</ref>
-=== Food and feeding ===
-Unlike most [[bird of prey|birds of prey]], the secretarybird is largely [[Terrestrial animal|terrestrial]], hunting its prey on foot. Adults hunt in pairs and sometimes as loose familial flocks, stalking through the habitat with long strides.<ref name="Janzen">{{ cite journal | last1=Janzen  | first1=D.H. | year=1976 | title=The depression of reptile biomass by large herbivores |  journal=American Naturalist | volume=110 | issue=973 | pages=371–400 [374–375] | doi=10.1086/283074 | jstor=2459760 | url=https://www.researchgate.net/publication/249139243 }}</ref>  Prey may consist of [[insect]]s, [[mammal]]s ranging in size from [[mouse|mice]] to [[hare]]s and [[mongoose]], [[crab]]s, [[lizard]]s, [[snake]]s, [[tortoise]]s, [[Bird|small birds]], [[bird egg]]s, and sometimes dead animals killed in grass or bush fires. Larger [[herbivore]]s are not generally hunted, although there are some reports of secretarybirds killing young [[gazelle]]s<ref name="Janzen" /> and cheetah cubs.<ref>{{Cite journal | last1 = Mills | first1= M.G.L. | last2 = Mills | first2 = M.E.J. | year = 2014 | title = Cheetah cub survival revisited: a re‐evaluation of the role of predation, especially by lions, and implications for conservation | journal = Journal of Zoology | volume = 292 | number = 2 | pages = 136–141 [139] | doi=10.1111/jzo.12087 | doi-access=free }}</ref> The importance of snakes in the diet has been exaggerated in the past, although they can be locally important and venomous species such as [[Bitis|adders]] and [[cobra]]s are regularly among the types of snake preyed upon. Secretarybirds do not eat carrion.<ref name=brown1982/>
-[[File:Sagittarius serpentarius -Namib-Naukluft National Park, Namibia -eating-8.jpg|left|thumb|In Namib-Naukluft National Park, Namibia]]
-Prey is often flushed out of tall grass by the birds stomping on the surrounding vegetation. 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.<ref name="four" /> 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.<ref name=ADW>{{cite web |url=http://animaldiversity.ummz.umich.edu/site/accounts/information/Sagittarius_serpentarius.html |title=''Sagittarius serpentarius'' : secretary bird |last=Sherman |first=Patrick |year=2007 |work=Animal Diversity Web |publisher=University of Michigan Museum of Zoology |accessdate=2018-01-19 |url-status=live |archiveurl=https://web.archive.org/web/20110615142035/http://animaldiversity.ummz.umich.edu/site/accounts/information/Sagittarius_serpentarius.html |archivedate=15 June 2011 |df=dmy-all }}</ref>
-Young are fed liquefied and [[Regurgitation (digestion)|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 (anatomy)|crop]] of the adults.<ref name="four" />
-The secretarybird has a relatively short digestive tract in comparison to other large African birds such as the [[kori bustard]].<ref>{{cite journal|last1=Maloly|first1=G. |first2=C.N. |last2=Warui | first3=E.T. |last3=Clemens|title=Comparative gastrointestinal morphology of the Kori bustard and secretary bird|journal=Zoo Biology|volume=6|issue=3|year=1987|pages=243–251|doi=10.1002/zoo.1430060307}}</ref> As the foregut is specialized for digesting large amounts of meat in a short amount of time, there is little need for the physical breakdown of food within the digestive tract over extended time spans.<ref name=portugal>{{cite journal | last1=Portugal | first1=Steven J. | first2=Campbell P. | last2=Murn | first3=Emily L. | last3=Sparkes | first4=Monica A. | last4=Daley | title=The fast and forceful kicking strike of the secretary bird|journal=Current Biology | volume=26 | issue=2 | year=2016 | pages=R58–R59 | doi=10.1016/j.cub.2015.12.004 | pmid=26811886 | url=http://researchonline.rvc.ac.uk/9958/1/9958.pdf}}</ref> The [[crop (anatomy)|crop]] of the secretarybird is dilated and the [[gizzard]] is nonmuscular in comparison to other birds.<ref name=duke>{{cite book|last1=Reece|first1=William O.|first2=Howard H.|last2=Erickson|first3=Jesse P.|last3=Goff|first4=Etsuro E.|last4=Uemura|title=Dukes' physiology of domestic animals|chapter=Avian digestion|publisher=ohn Wiley & Sons Incorporated|year=2015}}</ref> The large intestine lacks a [[cecum]] as there is little need for fermentative digestion of plant material.<ref name=mcnabb>{{cite journal|last=McNab|first=J. M.|title=The avian caeca: a review|journal=World's Poultry Science Journal|volume=29|issue=3|year=1973|pages=251–263|doi=10.1079/wps19730014}}</ref>
-Secretarybirds specialize in stomping their prey until the prey is killed or immobilized.<ref name=portugal />  This method of hunting is commonly applied to lizards or snakes.<ref name="Sinclair02">{{ cite book | last1=Sinclair | first1=I. | last2=Ryan | first2=P. | last3=Christy | first3=P. | last4=Hockey | first4=P. | year=2003 | title=Birds of Africa: South of the Sahara | location=Cape Town | publisher=Struik | isbn=978-1-86872-857-2 }}</ref>  An adult male trained to strike at a rubber snake on a force plate was found to hit with a force equal to 5 times its own body weight, with a contact period of only 10–15 ms. This short time of contact suggests that the secretarybird relies on superior visual targeting to determine the precise location of the prey's head. Although little is known about its visual field, it is assumed that it is large, frontal and binocular.<ref name=portugal />
-As secretarybirds are anatomically similar (but apparently not closely related) to the extinct [[Phorusrhacidae]], it has been hypothesized that these birds may have employed a similar hunting technique.<ref name=portugal />
-Secretarybirds have unusually long legs (nearly twice as long as other ground birds of the same body mass), which is thought to be an adaptation for the bird's unique stomping/striking hunting method. However, these long limbs appear to also lower its running efficiency.<ref name=portugal />
-== Relationship with humans ==
-=== Cultural significance ===
-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.<ref name =dehoyo />
-The secretarybird is the [[emblem of Sudan]], as well as a prominent feature on the [[coat of arms of South Africa]].<ref>{{cite web |title=The National Symbols |url=https://www.westerncape.gov.za/text/2016/April/national_symbols_poster_english.pdf |website=Western Cape Government |accessdate=23 December 2019}}</ref>
-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 (visual arts)|motif]] for African countries on [[postage stamp]]s: over a hundred stamps from 36 issuers are known, including some from [[List of entities that have issued postage stamps (A–E)|stamp-issuing entities]] such as [[Ajman]], [[Manama]], the [[Maldives]] and the [[United Nations]] where the bird does not exist.<ref name=stamps>{{cite web | author= Scharning, Kjell | title= Secretary Bird ''Sagittarius serpentarius'' | work= Theme Birds on Stamps | url= http://www.birdtheme.org/scripts/family.php?famnum=34 | accessdate= 18 January 2018 | url-status= live | archiveurl= https://web.archive.org/web/20180118181151/http://www.birdtheme.org/scripts/family.php?famnum=34 | archivedate= 18 January 2018 | df= dmy-all }}</ref>
-In the Disney film ''[[Bedknobs and Broomsticks]]'', one of the residents of Naboombu and the assistant to the king is a secretarybird. Both the secretarybird and the king are voiced by [[Lennie Weinrib]].
-=== Threats and conservation ===
-The [[International Union for the Conservation of Nature]] (IUCN) lists the secretarybird as a [[vulnerable species]], due to a recent rapid decline across its entire range,<ref name=IUCN /> particularly in South Africa.<ref name=hofmeyr14/> Although widespread, the species is thinly spread across its range; its population has been estimated at anywhere between 6,700 and 67,000 individuals.<ref name=IUCN />
-Long term monitoring across South Africa between 1987 and 2013 has shown that populations have declined in [[Kruger National Park]] as the vegetation cover has increased there, resulting in loss of open habitat that the species prefers.<ref name=hofmeyr14>{{Cite journal |doi = 10.1371/journal.pone.0096772|title = Secretarybird ''Sagittarius serpentarius'' Population Trends and Ecology: Insights from South African Citizen Science Data|journal = PLOS ONE|volume = 9|issue = 5|pages = e96772|year = 2014|last1 = Hofmeyr|first1 = Sally D.|last2 = Symes|first2 = Craig T.|last3 = Underhill|first3 = Leslie G.|bibcode = 2014PLoSO...996772H}}</ref>
-The young are preyed upon by [[Corvus (genus)|crows]], [[raven]]s, [[hornbill]]s, large [[owl]]s and [[kite (bird)|kites]] as they are vulnerable in ''Acacia'' tree tops, with no known incidents of predation on adults.<ref name="four" /> As a population, the secretarybird is mainly threatened by loss of habitat and deforestation.<ref name="Allan">{{cite journal | last1 = Allan | first1 = D.G. | last2 = Harrison | first2 = J.A. | last3 = Navarro | first3 = R.A. | last4 = van Wilgen | first4 = B.W. | last5 = Thompson | first5 = M.W. | year = 1997 | title = The impact of commercial afforestation on bird population in Mpumalanga Province, South Africa – Insights from Bird-Atlas Data | url = | journal = [[Biological Conservation (journal)|Biological Conservation]] | volume = 79 | issue = 2–3| pages = 173–185 | doi=10.1016/s0006-3207(96)00098-5| citeseerx = 10.1.1.625.4717 }}</ref>  In 1968 the species became protected under the Africa Convention on the Conservation of Nature and Natural Resources.<ref name="four" /> Loss of grassland to bush encroachment driven by rising CO<sub>2</sub> levels has also been implicated, as has a susceptibility to power line collisions.<ref name=simmons>{{cite book|chapter=Secretarybird – ''Sagittarius serpentarius'' |last=Simmons|first=R.E.|title=Bird to watch in Namibia – red, rare and endangered species|editor=R.E. Simmons |editor2=C.J. Brown |editor3=J. Kemper|publisher=Namibian Ministry of Environment and Tourism, and the Namibia Nature Foundation|year=2015}}</ref>
-== See also ==
-* [[Snake venom#Immunity|Snake venom immunity]]
-==Notes==
-{{Notelist}}
-== References ==
-{{Reflist}}
-== External links ==
-{{Commons|Sagittarius_serpentarius}}
-{{EB1911 Poster|Secretary-Bird}}
-* [http://ibc.lynxeds.com/species/secretarybird-sagittarius-serpentarius Secretary Bird videos, photos & sounds] on the Internet Bird Collection
-* [http://www.birdlife.org/datazone/speciesfactsheet.php?id=3562 Birdlife Species Factsheet]
-* [https://web.archive.org/web/20110929122633/http://www.arkive.org/secretarybird/sagittarius-serpentarius/ Secretarybird on ARKive]
-* [http://www.birdtheme.org/scripts/family.php?famnum=35 Secretary Bird on postage stamps]
-* [http://sabap2.adu.org.za/docs/sabap1/118.pdf Species text in The Atlas of Southern African Birds]
-{{Accipitriformes}}
-{{use dmy dates|date=June 2011}}
-{{Taxonbar|from=Q168748}}
-[[Category:Accipitriformes]]
-[[Category:Birds of Sub-Saharan Africa]]
-[[Category:Birds of prey]]
-[[Category:Birds of prey of Africa]]
-[[Category:Falconiformes (sensu lato)]]
-[[Category:National symbols of Sudan]]
-[[Category:Higher-level bird taxa restricted to the Afrotropics]]
-[[Category:Birds described in 1779]]
-[[Category:Taxa named by John Frederick Miller]]
-[[Category:Articles containing video clips]]