---
title: "What the sources say about the Secretarybird | AnimalTracks.wiki"
description: "50 claims from the Secretarybird profile, each beside the words of the source that backs it."
image: "https://animaltracks.wiki/images/animals/secretarybird-1.webp"
canonical: "https://animaltracks.wiki/animals/secretarybird/sources/"
---

# What the sources say about the Secretarybird (*Sagittarius serpentarius*)

> 50 claims from the Secretarybird profile, each beside the words of the source that backs it. A "..." marks a cut in a quote and [brackets] an insertion.

Profile: [Secretarybird](https://animaltracks.wiki/animals/secretarybird/)

## Secretarybird. The Peregrine Fund.

https://peregrinefund.org/explore-raptors-species/secretarybird

| The page says | The source says |
| :--- | :--- |
| the tallest bird of prey alive | The tallest raptor in the world |
| on the longest legs of any raptor | Secretarybirds have the longest legs of any bird of prey |
| a body weight of 2.2 to 4.3 kilograms (5 to 9.5 pounds) | Weight: 5-9.5 pounds (2.2-4.3 kg) (note: SDZWA gives 2.3 to 4.3 kg) |
| Heavy scales on its lower legs may help protect it while it walks through brush or attacks prey | their lower legs have heavy scales that may protect them while walking through the brush or when attacking their prey |
| It patrols the grass on foot for roughly 20 to 30 kilometers (12 to 18 miles) a day | Scientists estimate that Secretarybirds walk anywhere from 12 to 18 miles (20-30 km) a day |
| It lives in open savannas and grasslands south of the Sahara, from Senegal and Somalia down to South Africa | The Secretarybird is endemic to sub-Saharan Africa. It ranges from Senegal and Somalia all the way to the tip of South Africa. ... Secretarybirds prefer savannas, scrub, and grasslands |
| It is the only living member of its own bird family, Sagittariidae | they are the one and only member of the family Sagittariidae |
| A Species in Decline | Secretarybird populations are declining throughout much of their range |
| Numbers are falling across much of its range, and it has vanished from some areas entirely | Secretarybird populations are declining throughout much of their range and the species has disappeared entirely in some places (note: Peregrine page is current: it gives the 2020 status, Endangered) |
| Habitat loss is a huge problem: overgrazed land leaves little cover for its prey, and other land is cleared for farms and settlements | habitat loss is still a huge problem for this species. Areas that are over-grazed leave little cover for prey animals ... Other areas are being cleared for human settlements and agricultural fields |
| A young secretarybird can fall prey to owls or ravens, but an adult is rarely hunted by anything | Young Secretarybirds can fall prey to other predators such as owls and ravens, but adults are rarely preyed upon. |
| they are the only members of their own family, Sagittariidae | they are the one and only member of the family Sagittariidae |

## Secretary Bird. San Diego Zoo Wildlife Alliance.

http://animals.sandiegozoo.org/animals/secretary-bird

| The page says | The source says |
| :--- | :--- |
| standing 1.2 to 1.5 meters (4.1 to 4.9 feet) tall | Height: 4.1 to 4.9 feet (1.2 to 1.5 meters) tall (note: SDZWA gives height; Peregrine's 1.2-1.5 m is body length) |
| a wingspan around 2.1 meters (6.9 feet) | WIngspan: 6.9 feet (2.1 meters) (note: Peregrine gives 7 feet (2 m); 'around' covers both) |
| It can live 10 to 15 years, and up to 19 in a zoo | LIFE SPAN 10 to 15 years; up to 19 years in zoos |
| Its feet are built for walking, with little grip, and it hunts on foot | hunting for their food on foot ... The secretary bird's feet are adapted for walking and lack significant grasping ability. |
| A venomous snake may bite at its flapping feathers, but they make safe targets, because a bite to a hollow feather does not hurt the bird at all | A venomous snake might try to bite the secretary bird’s flapping feathers, but they serve as safe distractions or targets, since a bite to a hollow feather wouldn’t hurt the bird at all! |
| then roosts high in an acacia tree at night | secretary birds are good fliers and nest and roost high up in acacia trees at night |
| Distantly | Secretary birds are distantly related to buzzards, vultures, harriers, and kites. |
| They are related to buzzards, vultures, harriers and kites | Secretary birds are distantly related to buzzards, vultures, harriers, and kites. |
| Unlike those raptor cousins, they spend most of their time on the ground | But unlike their raptor cousins, secretary birds spend most of their time on the ground. |

## Sagittarius serpentarius. Animal Diversity Web, University of Michigan.

https://animaldiversity.org/accounts/Sagittarius_serpentarius/

| The page says | The source says |
| :--- | :--- |
| From Grasshoppers to Cobras | arthropods (including grasshoppers ... the snakes taken as prey are often adders, cobras, and other venomous species |
| Small prey it simply catches in its bill | With small prey, the bird will merely bend down and capture it in its bill. |
| Its menu runs from grasshoppers, beetles and scorpions to mice, hares, small birds, lizards and small tortoises, plus snakes, often adders and cobras | arthropods (including grasshoppers, beetles, spiders, scorpions, wasps, etc.) and small mammals (including mice, rats, hedgehogs, hares, mongooses, etc.) ... small and young birds, eggs, amphibians, freshwater crabs, lizards, small tortoises, chameleons and snakes ... the snakes taken as prey are often adders, cobras, and other venomous species |
| snakes make up a smaller share of its diet than its reputation suggests | Although this species is famed for killing and eating snakes, these reptiles are not eaten as often as is generally believed. |
| A Raptor That Would Rather Walk | Secretary birds prefer to walk rather than fly |
| A secretarybird flies well, often at great heights, but it would rather walk | Secretary birds prefer to walk rather than fly ... When they do fly, they fly well and often at great heights. |
| walking at a steady pace and searching for movement | The birds will set out across a grassy area at a steady pace searching for movement. |
| usually in a pair or family group, sometimes alone | is sometimes solitary, but is more often found in pairs or family groups |
| The name may come from its crest feathers, which made these birds look like old-time secretaries with quill pens tucked behind their ears | The origin of the common name may come from the fact that their crest feathers made these birds look like old-time secretaries who used to keep their quill pens tucked behind their ears. |
| That explanation has been challenged, though | In recent years, however, this has been challenged. (note: ADW is dated 2007; SDZWA (current) also says the quill story 'was once thought') |
| some think the name instead comes from the Arabic 'saqr et-tair', which might mean 'hunter bird' | It is instead thought by some that the name comes from the Arabic 'saqr et-tair'. 'Saqr' means "hunter" or "hawk" and 'et-tair' means "flight" or, in general, "bird". Thus, 'saqr et-tair' might mean "hunter bird" |
| Open savannas, grasslands, and semi-arid plains of sub-Saharan Africa | is found throughout Africa south of the Sahara ... Secretary birds prefer open savannahs and grasslands, although they also live in semi-deserts (note: 'semi-arid plains' for 'semi-deserts') |
| Grasshoppers, beetles, rodents, lizards, small tortoises, and snakes such as adders and cobras | arthropods (including grasshoppers, beetles, spiders, scorpions, wasps, etc.) and small mammals (including mice, rats, hedgehogs, hares, mongooses, etc.) ... lizards, small tortoises, chameleons and snakes ... the snakes taken as prey are often adders, cobras, and other venomous species (note: 'rodents' for mice and rats; a category list, not an exclusivity claim) |

## Portugal et al. (2016). The fast and forceful kicking strike of the secretary bird. Current Biology.

https://doi.org/10.1016/j.cub.2015.12.004

| The page says | The source says |
| :--- | :--- |
| The stilt-legged snake executioner whose stomp, measured in one captive male, peaked at five times his body weight on average | the peak force demands of secretary bird kicking strikes are remarkably high (Figure 1C), averaging 5.1 ± 0.9 body weights (195 ± 34 N, mean ± s.d.) (note: 195 N is the mean of the peak forces, not one kick. One captive male: the Royal Holloway release says the study 'focuses on a captive male Secretary Bird called Madeleine') |
| Stomping kicks: one captive male's peak force averaged five times his body weight, his foot on the snake for about 15 milliseconds a strike | averaging 5.1 ± 0.9 body weights (195 ± 34 N, mean ± s.d.) ... lasting only 15 ± 4.4 ms duration in contact |
| His kicks peaked at an average of 195 newtons, equal to five times his own body weight, and his foot touched the snake for an average of just 15 milliseconds | averaging 5.1 ± 0.9 body weights (195 ± 34 N, mean ± s.d.) ... lasting only 15 ± 4.4 ms duration in contact |
| A secretarybird often kills by kicking and stamping on its prey's head until the animal is stunned or dead, especially a larger lizard or a venomous snake | They frequently kick and stamp on the prey's head until it is killed or incapacitated, particularly when dispatching larger lizards and venomous snakes |
| His kicks peaked at 195 newtons on average, about five times his own body weight | averaging 5.1 ± 0.9 body weights (195 ± 34 N, mean ± s.d.) |

## Snake-hunting secretary birds use the force of five times their body weight to stamp on and kill their prey. Royal Holloway, University of London (via Phys.org), 2016.

https://phys.org/news/2016-01-snake-hunting-secretary-birds-body-weight.html

| The page says | The source says |
| :--- | :--- |
| To measure its kick, researchers pulled a rubber snake across a force plate hidden under artificial grass in the enclosure of Madeleine, a captive male trained to attack it | a captive male Secretary Bird called Madeleine ... Madeleine was trained to attack a rubber snake ... The scientists measured Madeleine's kicks by putting a force plate (hidden under artificial grass) in the bird's enclosure and pulling the rubber snake across the force plate. |
| A Tenth of a Blink | The exceptionally rapid strike contact duration is 1/10th of the time it takes to blink an eye |
| Madeleine's foot stayed on the snake for about a tenth of the time it takes to blink, which lasts around 150 milliseconds | The exceptionally rapid strike contact duration is 1/10th of the time it takes to blink an eye – which takes around 150 ms. (note: the blink duration is the researcher's comparison figure, not a bird figure) |
| The researchers concluded that a contact that brief, on legs that long, is too fast to steer by feel, so the bird aims by eye and plans each kick in advance | Such rapid time, coupled with the exceptionally long legs, means the birds can't be using proprioreception – the sixth sense we use to sense our position and movement. Therefore, they are using visual targeting and feed-forward motor control – (pre-planned movements) (note: 'steer by feel' is proprioception, 'the sense we use to sense our position and movement') |
| Once a kick starts it can't be adjusted, so a miss can only be corrected with the next one | the birds can only correct for a missed strike in the next kick – once they've started a kick, they can't adapt it |
| In a study at the Hawk Conservancy Trust, researchers measured a captive male secretarybird named Madeleine attacking a rubber snake pulled across a hidden force plate | focuses on a captive male Secretary Bird called Madeleine, held at the Hawk Conservancy Trust, Hampshire. Madeleine was trained to attack a rubber snake ... The scientists measured Madeleine's kicks by putting a force plate (hidden under artificial grass) in the bird's enclosure and pulling the rubber snake across the force plate. |
| his foot touched the snake for an average of just 15 milliseconds | the contact time between the bird's feet and the snake is delivered extremely quickly - on average just 15 milliseconds |
| roughly a tenth of the time it takes to blink, which lasts around 150 milliseconds | The exceptionally rapid strike contact duration is 1/10th of the time it takes to blink an eye – which takes around 150 ms. |
| The researchers concluded that a contact that brief, on legs that long, has to be aimed by eye and planned in advance, so a miss can only be corrected with the next kick | Such rapid time, coupled with the exceptionally long legs, means the birds can't be using proprioreception ... Therefore, they are using visual targeting and feed-forward motor control – (pre-planned movements) - during strike events. This means the birds can only correct for a missed strike in the next kick |
| matching a stomp whose measured contact with the snake lasted 15 milliseconds on average | the contact time between the bird's feet and the snake is delivered extremely quickly - on average just 15 milliseconds (note: the measured stomps are Madeleine's, the one captive male in the study) |

## Sagittarius serpentarius. The IUCN Red List of Threatened Species 2020: e.T22696221A173647556.

https://doi.org/10.2305/iucn.uk.2020-3.rlts.t22696221a173647556.en

| The page says | The source says |
| :--- | :--- |
| The IUCN lists the secretarybird as Endangered | IUCN Red List category: Endangered (EN). |