Game Ranging / Field Guiding Course. Giraffe

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1 1 Module # 7 Component # 16 Classification Giraffe Giraffe are classified in the following manner: Kingdom - Animalia Phylum - Chordata Class - Mammalia Order - Ruminantia Family - Giraffidae Genus - Giraffa Species - camelopardalis Common names: English - Giraffe German - Giraffe French - Girafe Afrikaans - Kameelpaerd Zulu - Ndlulamithi Swahili - Twiga

2 2 Family Giraffidae There are only two genera with a species each in the Family Giraffidae. One is the giraffe, and the other is the Okapi - Okapia johnstoni. Okapis are extremely rare, occurring only in central Africa. They have shorter necks and legs and are differently coloured. They are solitary and very elusive. Among the other giraffe genera there are several sub species, although the one that follows is the only one present in South Africa.

3 3 Myth & Legend In the days when the world was still new, all the plant eating animals lived on the wide-open plains and all ate grass. The buffalo ate grass, the zebra ate grass, the antelope ate grass and the giraffe ate grass; and all were satisfied. One day the zebra became disgruntled and complained to the other animals that he was tired of eating grass and wanted something else. On hearing the lament the other animals at first ignored the zebra, but soon began to comment that a change from grass would indeed be well received. The elders of each animal group then held an indaba (a meeting) to discuss what might be done. What can we do? asked the antelope and buffalo. I have an idea said giraffe. There is a story among my kind that there is a spirit of the plains, perhaps it can help us. It is believed that that it appears only once a year on longest night. If we were to stay awake, we would be able to speak with it. All the elders quickly agreed that giraffe had a good idea and all volunteered to stay awake on longest night to speak with the spirit of the plains. After much bickering about which animal would have the honour, they finally decided that one member of each group would stay awake. If the spirit appeared, it would have the choice of which animal it wished to speak with. As the special night approached all the animals grew excited, and on the day of longest night, the elders assembled once again, each bringing its chosen emissary. As the sun set, the small group of chosen animals wandered some distance away from the now sleeping herds to await the arrival of the spirit. The night grew very dark and cold and one by the one the chosen animals began to drift off to sleep, until only the giraffe remained. Many hours passed and just as the giraffe was on the verge of falling asleep, the spirit of the plains appeared.

4 4 What have you to say to me demanded the spirit of the frightened giraffe. We have come to ask you for something else to eat besides grass. replied the giraffe. Who is the we that you speak of? asked the spirit. I see only you. I am here with the antelope, the buffalo and the zebra whispered the giraffe. But they lie there and sleep. Said the spirit Do they not want the same as you and your people, and if so why do they not show me the same respect? I cannot answer said the now trembling giraffe. Worry not replied the spirit. rest now, you will know my decision in the morning. As the sun rose, the animals rose early with it in expectation of what they might find. The sight that greeted them was almost impossible to comprehend, for all around them trees covered with delicious leaves had sprung up, peppering the plains in all directions. Joy soon became disappointment, as all the trees were twice the height of the buffalo, antelope and zebra, and only the giraffe was able eat.

5 5 Vital Statistics Males Females Total Height 5.50m (18ft) 4.20m (14ft) Shoulder Height 3.30m (11ft) 2.80m (9ft) Weight 1200kg (2640lbs.) 830Kg (1830lbs.) Gestation period 15 months Food preference Browser Maximum speed 56kph (± 35mph) Social grouping Temporary association Longevity ± 28 years Record Game Auction price R 44, Record horn length 15.5cm (6.2in.) Giraffe - Giraffa camelopardalis (Linnaeus 1759)

6 6 Introduction These animals are impossible to confuse with any other. They are the tallest land animals with a height of up to five and a half metres. Both sexes exhibit horns of an average 13 ½ cm's [5.4 in] long. Their horns in fact differ from the horns of other species, being bony-covered cartilage extensions of the skull rather than modified hair, and are thus covered with skin and hair. The horns are also the main indicator of gender. The males are knobbed and hairless at the tips, while the females are thin and tufted. One further method of correctly identifying the gender of a giraffe is by its browsing stance. Males browse with the necks extended almost straight up, while females browse with their necks bent, feeding on leaves at their own shoulder height. The scientific name is derived from their size and coat markings, being as big as a camel and spotted as a leopard. The word giraffe has its origins in the Arabic word xirapha, which means the one who walks swiftly.

7 7 Food and Feeding Being of this height, giraffes can only be browsers. They also have access to the taller parts of trees out of reach of all other animals except the elephant, and thus avoid competition with all the other browsing species. They feed off over a 100-different species of trees, but prefer Acacias. Their remarkably long (45 cm / 18 in.) and highly dextrous tongue greatly aids in their foraging. Their tongue enables them to select individual leaves from between thorns if desired, although they have horny projections on their tongue, lips and mouth to protect against the sharpest and strongest of thorns. Also, being of this immense size, they must eat a great deal, and an average of 34 kg [75 lbs.] of plant matter are consumed daily. Giraffe are classified as concentrate selective feeders. They are diurnal, meaning that they are mostly active during the day, but will move around and feed at night on occasion.

8 8 Drinking from 5.5m (18ft) up Giraffe obtain a good percentage of their moisture requirements from their diet, but still need to drink every two to three days. This highlights a significant problem for these animals in terms of blood flow. Firstly, it needs and has a massive heart to pump blood some two to three metres [12 18 ft] up from its heart to head. And then when it bends its neck to drink, it needs to prevent excess blood flow to the head. At one moment, it is pumping blood against gravity, and the next with it. These problems are solved with a unique set of elastic blood vessels and a complex system of valves. These ensure that the giraffe gets the correct amount of blood to the brain at the appropriate time. The posture that giraffe need to adopt when drinking leaves them extremely vulnerable to attack, thus giraffe remain exceedingly alert at waterholes. When giraffe come down to drink in a group, you may notice that at least one of the group will always have his / her head up and will be watching closely for any signs of predators while the others bend down to drink.

9 9 The Neck and Walk The giraffe s distinctly sloping back is not due to short hind legs like the hyena, but rather due to the great bulk of muscles needed to support its huge neck. One characteristic common to all land mammals is our number of neck vertebrae, and this is true of giraffe too, having seven just like we do. Each is very large, which restricts its flexibility somewhat. One further very distinctive feature of this very distinctive animal is its walk or gait. Because of its very long legs and relatively short body, giraffe cannot move in the same fashion as all other four legged animals, with alternate legs moving together. Instead it walks by moving both legs on the same side together. Many would assume that this slows it down significantly, but giraffe can gallop at speeds of up to 50 Km per hour [30mph]. The incredible height of giraffe has not precluded them from many of its activities. Giraffe are quite able to lie down and take short naps of only a few minutes at a time. When they do sit, or lie down, they do so by folding their legs underneath their body, and get up and down in the same fashion as camels. Giraffe have also been recorded to have jumped a fence of at least 1.5 m [5 ft] high. They have not, however, ever been recorded to swim.

10 10 Social Grouping Giraffe are gregarious, although when together they don't behave like members of the same herd. The only time they are seen in close association is when they are feeding from the same tree. They group loosely and a herd of a dozen feeding giraffe may be spread over an area of a 1 2 Km or more. They have large overlapping home ranges, and each collection of individuals has no leader and shows little in the way of co-ordinated movement. This form of sociality is termed a temporary association. Despite this giraffe females are seldom seen alone, and are usually in sight of other females. Males tend to associate in loose bachelor herds, beginning at puberty at three years. As they mature they become increasingly solitary, dividing their time between feeding and monitoring the reproductive status of the females in their core range. However, male giraffes in herds or alone frequently mingle with females and young. Consequently, giraffe herds may contain any combination of sexes, ages and numbers at any time, and the composition will almost certainly change within hours. Variability is basically the only rule. Males establish some form of dominance over each other, and dominance carries with it the right to mate. This is established by a form of fighting. Here the males stand shoulder to shoulder, or head to tail, and aim hefty blows at one another with their heads. This usually results in a series of clashing of their necks. Injuries are few, but a few giraffe necks have been broken. There are several records of giraffe with distinct neck kinks, probably due to previous broken vertebrae.

11 11 Reproduction Once a male finds a female in oestrus, he follows her around and chases off all other males. After a gestation of 457 days or little over 15 months a single calf is born, which may weigh up to 60 kg [130lbs.]. Giraffes give birth standing up, and the calf falls almost two metres [6 ft], snapping the umbilical cord in the process. They stand nearly two metres [6.6 ft] tall, which is necessary for them to be able to reach their mothers udder. Mother and calf stay together alone for a few days, and then all new calves in the area are brought together. One or two adults supervise this nursery herd while the others go off to feed. They suckle their young twice a day and stay with them at night. They are weaned at 18 months. Males are fully grown at seven and females at five years old Giraffe leave an interesting legacy in areas where they have been. These are hour glass - shaped trees. This occurs when giraffe feed on trees taller than they are, and basically eat out the middle of the tree all the way round. Giraffe are one of the more numerous species of African game. They can live to be 28 years old.