Birds
Secretary Bird
Sagittarius serpentarius · also called secretarybird
The secretary bird is a bird of prey that gave up the ambush from above and became a walker. Standing over a metre tall on long, scaled legs, it strides across the African plains all day, and it dispatches its prey — snakes included — with some of the fastest, hardest kicks in the animal world.
Overview
Secretary birds live in the open grasslands and savannas of sub-Saharan Africa, from Senegal to South Africa, wherever the ground is grassy and not too wooded. A pair holds a large territory — sometimes 20 to 200 square kilometres — and patrols it on foot, covering long distances daily. They are usually seen singly or in pairs, walking with a measured, upright gait, and they roost and nest in the flat crowns of acacia and other thorn trees.
An eagle on stilts
The secretary bird is a true raptor — related to hawks, eagles, and vultures — but built for the ground. It has the hooked bill and sharp eyesight of a bird of prey mounted on a body with crane-like legs, short toes with blunt talons (for striking, not gripping), and a long central pair of tail feathers. The bare skin of the face is red-orange, and a spray of black crest feathers stands out behind the head.
Hunting on foot
Secretary birds forage by walking through grass and stamping the ground to flush hidden animals, then chasing them down. Small prey is snapped up in the bill; dangerous or larger prey — snakes, big lizards, rodents — is killed by kicking. High-speed studies have measured the strike at roughly five times the bird’s body weight, delivered in about 15 milliseconds, aimed at the head, and repeated until the prey is dead. Against snakes the bird spreads its wings as a shield and moves too fast for the snake to land a bite. This makes secretary birds significant predators of venomous snakes across their range.
Reproduction
Pairs perform undulating display flights and a grounded “courtship dance,” then build a broad, flat stick platform on top of a thorn tree, reused and enlarged year after year. The female lays one to three eggs; typically one or two chicks fledge. The young are fed regurgitated food and then whole small prey, and remain dependent for some weeks after leaving the nest.
Threats and conservation
The secretary bird was uplisted to Endangered as evidence of a widespread, ongoing decline accumulated. The central problem is the loss and degradation of open grassland — to cropland, heavy grazing, and bush encroachment — which shrinks its hunting habitat. Added to this are collisions with power lines and fences, poisoning, nest disturbance, and capture for the pet and traditional-use trade. Conservation priorities are protecting large tracts of grassland, marking or burying dangerous power lines, and reducing the use of poisons on farmland and rangeland.
Secretary Bird: common questions
Why is it called a secretary bird?
The traditional explanation is that the crest of long dark feathers at the back of its head looked, to 18th-century Europeans, like the goose-quill pens a law clerk or secretary would tuck behind the ear, and its grey-and-black plumage resembled a clerk's tailcoat and knee-breeches. A competing idea is that the name comes from a corruption of an Arabic term, "saqr et-tair" (hunter bird). The quill-pen story is the popular one.
How does a secretary bird kill a snake?
By stamping. It approaches with wings partly spread as a shield and distraction, then delivers rapid, precisely aimed kicks to the snake's head and body. High-speed video shows the strike lasts about 15 milliseconds — too fast for a snake to bite back — and lands with a force around five times the bird's body weight, enough to stun or kill outright. The bird then either swallows the prey whole or stamps it into pieces. It uses the same technique on rodents, lizards, and large insects flushed from the grass.
Can secretary birds fly?
Yes, well. Although they do almost all their hunting on foot and walk enormous distances each day, secretary birds roost in the flat tops of acacia trees, build their large stick nests there, and soar on thermals like other raptors, especially in courtship display flights and when moving between areas. Chicks branch and fledge from the treetop nest at around 65–105 days.
Why is the secretary bird endangered?
Its grassland habitat is being lost and fragmented by farming, overgrazing, and the spread of bush and trees into open plains, which the bird avoids. It is also killed on power lines and fences, poisoned (deliberately and as bycatch of predator control), disturbed at the nest, and captured for trade. Because it is spread thinly over a huge area and breeds slowly, these losses have added up to a steep enough decline for the species to be uplisted to Endangered.