Struthio camelus
The ostrich (Struthio camelus) is a species of strutioniform bird in the family Struthionidae. It is a large, flightless bird, but she is a runner. It is found in Africa, and in past times it also inhabited the Middle East. It is the largest and heaviest of the birds that still exist; It can reach three meters in height and weigh about 180 kg.
Description
It is the largest and heaviest bird in the world. When the chicks hatch they are between 25 and 30 cm tall, weighing about 900 g. During the first year of life, the chicks grow about 25 cm per month. Adult males can reach 2.75 or even 3 meters, and weigh around 180 kg.
Their small wings do not allow them to fly, yet they help them propel themselves, balance when running, and as a defense mechanism, flapping them to attack potential predators.
It has a small head in relation to the body, large eyes that measure two inches in diameter and provide excellent vision, a flat, blunt-tipped beak, a long neck devoid of feathers as well as its long legs, which are powerful. and muscular, perfectly adapted for running, reaching more than 70 km/h for about thirty minutes. If cornered they attack with strong kicks using their claws as weapons. While most birds have four toes on each foot, the ostrich has only two.
Their longevity is between thirty and forty years, although in captivity they can reach fifty years.
Sexual dimorphism
The male, in general, reaches about 2.75 m. Its plumage is black, with the tips of the wings and tail white.
The female measures about 2.30 m, the color of its plumage is gray. The color of the plumage in the females depends on the presence of estrogens, therefore, the immature or sterilized females present a black plumage.
Song
Due to the anatomical characteristics of the ostrich's syrinx, it does not emit songs like other birds do. However, they occasionally manifest a kind of high-pitched hiss. On the other hand, the ostrich pups in a state of alteration launch a strident cry, although more characteristic are the whistles and gurgles as a call that they emit until they reach the month of birth.
In addition, the adult male emits a bravura call when he wants to establish his territory and warn other competing specimens, as well as to control his own young. The phonation emitted for it consists of a slight hoarse sound similar to a bellow or sometimes described as a nasal growl that can be reminiscent of that of a lion. They can also use it during the wedding procession, where it seems more profound.
Females, on the contrary, do not present any phonation, since the only sound they emit throughout their adult life is something similar to a cluck when they are courted by the male.
Playback
- Cutting and mating
Their reproductive behavior is highly variable, depending on population density, climatic conditions, and habitat. Males reach maturity at around three years of age. Females, if well fed, can reach this maturity about six months earlier.
During the mating season, in mid or late May, both the male's neck and beak turn reddish (due to the action of testosterone), and that is when they become highly territorial, defending an area or territory.
To get to copulation, males perform a careful nuptial procession. Lying down on the ground, they sit on their legs with their wings open, lifting and tucking in one wing after the other synchronously, while making an oscillating movement of the head and neck, as well as raising and lowering the tail. The fan-shaped white feathers, both on the wings and on the tail, give the male the necessary attraction to mate with the female, who will circle around her, flapping her wings and lowering her head to show herself receptive. This dance or ritual lasts approximately ten minutes, and after its completion, intercourse begins, the male's reproductive organ being the penis, which can reach up to 40 cm long, introduced into the female's vagina or reproductive organ through the so-called seminal groove.
- Nest and incubation
The male is in charge of building the nest, which consists of a depression dug in the ground. From that moment on, the chosen female, called the main female, is the first to lay her eggs, since the male repeats the nuptial procession with other females, generally mating with three in total, and can reach up to five.. These females are called secondary females, which will also lay the eggs in the same nest, just a few days after the first female and with her prior consent, although they do not participate in the incubation since they leave after laying.. The clutch can reach forty eggs, of which probably only about thirty will survive. In nature, as a free and wild animal, each female can lay from ten to fifteen eggs. However, in captivity, each female lays about fifty eggs per season.
Ostrich laying occurs from March or April to October or November, therefore being seasonal. The male is usually in charge of incubating the eggs at night, and the female (his partner or main female) does it during the day for a period of between thirty-nine and forty-two days (it is important to note that the male incubates a greater proportion of the time than the female, about 65%). At night, all the male ostriches that share their territory alternately exchange incubation positions, in the event that a clueless male does not find his nest, with the fatal loss of the chicks.
- Egg
An ostrich egg weighs between 1 and 2 kg (equivalent to about twenty-four chicken eggs). They are white or yellowish in color (possibly this prevents them from overheating in the savannah sun).
Their eggs are the largest of any bird; They reach 25 cm in length.
- Eclosion and upbringing
When the eggs hatch, the male takes care of the young (with the help of the female), and can gather young from several families together, since when two different families of ostriches meet, the parents of both quarrel the right to care for the chicks. You can see couples with more than a hundred young and of all sizes, in fact a group of almost four hundred young has been documented.
Ecology
Distribution and habitat
Its geographical distribution occurs in arid and semi-arid zones, so its habitat can include places with thermal oscillations between -15 and 40 °C (night and day), places with great thermal amplitude, and a rainfall of 200 mm. It occupies open spaces, where its height allows it to spot potential predators that approach, living both in deserts and in savannahs, or in plains with sparse vegetation where there are some trees, shrubs and grass to feed on. These habitats are preferably found in Africa and Arabia.
About 90% of wild ostriches live in Africa, south of the equator.
The nominate subspecies, the only survivor north of the equator, is in serious danger of extinction. Among the attempts to conserve this species, its introduction into the Souss-Massa National Park, in Morocco, stands out with the aim of acclimatizing it to natural conditions and, later, proceeding with its release in its former area of distribution when it can be guaranteed. survival.
Food
The ostrich, like all birds, lacks teeth and has little mobility in the tongue, so it does not chew what it eats. It takes food with its beak and advances it towards the opening of the esophagus.
It is a herbivorous animal with the ability to digest fiber, although it is not a strict herbivore; in fact, some authors consider it omnivorous, since it can eat small animals and arthropods. It has even been observed consuming carrion remains left behind by carnivorous animals.
When consuming vegetables, they prefer flowers and fruits, generally discarding the leaves. In their voracity they can ingest stones, rocks or minerals, which retained in their organism help to grind food. They have, therefore, a great appetite, not resisting fasting for too long, but in the wild they can endure long periods without drinking water (just like the camel), although depending on the age, the size of the ostrich and other factors this can affect it. in one way or another; in captivity and in specimens from four to six months, if the lack of water is prolonged for more than forty-eight hours, an approximate decrease in body weight is observed by 30% and it is observed that, after twenty-four hours with water deprivation, the animal considerably reduces its feed intake.
Unlike most birds, ostriches do not have a crop in which to store food; on the contrary, its proventriculus and gizzard are longer than those of other birds and in proportion to their bodies, so that is where it will store and ferment everything it eats. In addition, the gizzard of ostriches has a thick wall of highly developed muscle layer.
Taxonomy
The ostrich was originally described by the Swedish scientist, naturalist, botanist and zoologist Karl Linnaeus in his work Systema naturæ, under its current binomial name. Its scientific name is derived from the Latin struthio which means "ostrich" and camelus meaning "camel", alluding to its dry habitat.
Ostriches belong to the order Struthioniformes, also called ratites. Characterized by the absence of a keel on the sternum. The ostrich belongs, within this order, to the family Struthionidae (until recently it was considered its only non-extinct representative; as of 2006 another species, Struthio molybdophanes), was recognized.
Ostrich Subspecies
The following subspecies are recognized:
Conservation status
The population of wild ostriches has declined dramatically in the last two hundred years, with the majority being in reserves and farms. However, their distribution remains wide ( 9,800,000 km²) for which the International Union for Conservation of Nature and BirdLife International treat it as a species of least concern. Of its four subspecies, the Arabian ostrich (S. c. syriacus) became extinct around 1966, and the North African ostrich (S. c. camelus) has declined to the point that it is now listed on CITES Appendix I and is treated by some as critically endangered.
Relationship with the human being
Common name
The word «ostrich» comes to Spanish from the Provençal Occitan «estrutz», which derives from the Latin «struthĭo», and this from the Greek «στρουθíων ”, abbreviation of “στρουθοκάμηλος”, a word composed of “στρουθιο” (struthio = sparrow) and “κάμηλος” (kámēlos = camel), that is: "sparrow (big as a) camel".
The Royal Spanish Academy defines it as masculine (the black ostrich), and also the Pan-Hispanic Dictionary of Dudes, pointing it out as incorrect "the ostrich".
Domestication
The domestic ostrich, black-necked or african black (Struthio camelus domesticus), is a crossbreed, developed from the subspecies Struthio camelus camelus and Struthio camelus australis, therefore it does not exist in the nature.
Smaller in size than the other subspecies of ostriches, it has a less aggressive behavior, which allows for easier handling in hatcheries and in the ostrich industry.
The domestication and farming of ostriches can be directed towards the production of meat, skin, feathers and eggs. Based on these productions, the ostrich is exploited throughout the world, being an animal that adapts well to different climates. Some producing countries are: South Africa, Namibia, Israel, Australia, United States, Canada, France, Spain, Great Britain, Holland, Belgium, Germany, Italy, Ukraine.
Myths about the ostrich
The widespread belief that in the presence of danger the ostrich hides its head under the ground is false, the most they do is lower their heads to ground level to go unnoticed and look like a bush. Although the usual thing is that they run away or attack with their powerful legs. Chicks also have this behavior when faced with danger. Therefore, the phrase "hide your head like an ostrich" has no foundation.
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