Giraffe

Giraffe

 

Giraffe

Order: Artiodactyla                                                                               Family: Giraffidae                                                

Scientific name: Giraffa camelopardalis                                             U.S. common name: Giraffe    This will include all subspecies of giraffe.

Other names: Twiga (Swahili)  

Status in the wild: Classified as conservation dependent by IUCN. G. c. camelopardalis is the most restricted and most endangered subspecies. 

Major threats: Excessive hunting and habitat loss.  

Geographic range historically: Most of the open country in Africa  

Geographic range currently: Now restricted to areas south of the Sahara 

Habitat: Dry savannah especially with acacia, open woodland, and seasonal floodplains, most common in areas with scattered low and medium-height woody

               growth. 

Circadian cycle: Primarily crepuscular. 

 

Size

 

General range                       male                                       female                                                    birth

 

Head to rump length:                               3.5-4.8 m                                                                                                                                                            

Tail length:                                               0.76-1.1 m                                                                                                                                            

Head & tail length:                                  4.26-5.9 m                                                                                                                                                          

Total height:                                             3.5-5.2 m                          3.9-5.2 m                                3.5-4.7 m                                                 1.7-2.2 m 

Weight:                                                      450-1930 kg                     1800-1930 kg                         450-1180 kg                                            47-70 kg     

Sexual dimorphism: Males generally larger than females. Both sexes carry horns, the ends knobbed hairless in adult males, and thin and tufted in females and

                                     young; a median, lumpy horn and four or more smaller bumps in the males only.  Horns are present in utero, are formed of cartilage

                                     from a layer of skin and unattached to the skull. They lie flat but within a few days of birth stand erect. Growth proceeds from the

                                     base, but bone deposition begins at the tips and proceeds downward. Fusion with skull occurs at 4-4.5 years in males and after 7 years

                                     in females. The giraffe’s main pair of horns attaches to the parietals rather than the frontal bones as in deer and antelope. Male horn

                                     growth continues through a process where bone of dermal origin is deposited over the whole surface of the skull except where muscles

                                     attach. Apart from the parietal and median horns, bone accumulates as knobs at the base of the skull, over the eyes, and on the nose.                                                                       

 

Reproduction

 

Mating Season: Throughout the year but with most mating occurring during the rains. 

Birthing season: Throughout the year.  

Gestation period: 14-14.5 months  

Courtship: Once an estrus female is located, a male attempts to maintain a tending bond and keep rivals away. He follows the female closely, licking her tail,

                    and sometimes taking it between his lips, standing and urine testing when she urinates. He may rest his head on her rump, nudge her with his

                    muzzle, butt her gently with his horns, try to rest his neck on back. Moving in closer, he foreleg-lifts, which causes her to move forward.  

Copulation: When she is ready to stand for copulation, he stand immobile with his head high, then mounts by sliding his forelegs loosely onto her flanks, and

                      stands upright while giving an ejaculatory thrust that sends the female forward and ends the courtship bout.  

Number of mammae: Four  

Interbirth interval: 20-23 months  

Sexual maturity: At 3.5 years in females, and 4.5 years in males although males are not able to compete for breeding until full size is reached at 7 years.  

Other information: Females usually calve in discreet calving grounds. The female remains in isolation with the calf for about one week, the calf then joins

                                   other calves in a crèche during the day while the female feeds.  

 

Rearing and young

 

Young called: Calf 

Number of young (range): One, rarely two. 

Condition of young: Precocial 

Eyes open: At birth              

First leave pouch/den/hide/nest: The female remains in isolation with the calf for about one week, the calf then joins other calves in a crèche during the day

                                                        while the female feeds. 

First take solids: 3-4 months when rumination begins.  

Weaned: 6-13 months  

Independent: 12-16 months 

 

General

 

 

Life expectancy: Up to 25 years in the wild, up to 36 years in captivity.  

Social structure: Females and young associate in herds of 2-10 animals. Young males form bachelor herds and will join these herds at about 3 years of age.

                              They usually emigrate out of their natal range. As males mature they become increasingly solitary. Calves form crèches of up to 9 animals

                              which provides protection for the young while the females feed during the day. Male dominance hierarchy is largely a function of seniority

                              and between peers is usually decided before maturity through contests in the bachelor herd. This is done through “necking”, a behavior in

                              which two animals swing their head and neck at an opponent attempting to land a blow on the rump, flanks, or neck. Blows seldom land

                              solidly as each animal attempts to avoid being hit by moving his neck or body away at the last moment. The necks and jaws of adult

                              giraffes are occasionally broken in such contests.  

Unique behavior(s): There is vertical separation in feeding between males and females. The typical feeding stance of an adult male is with the head and neck

                                    at full vertical stretch, often with the tongue extended. Females tend to stand with the neck curled over, feeding at body or knee height.

                                    This reduces food competition between the sexes.  Can run at speeds of 60 kph.  

Senses: The best developed sense is sight, but hearing and olfaction are acute as well.  

Coat & coloration: The color pattern of the coat varies depending on subspecies but in general consists of dark reddish to chestnut brown blotches of

                                  various shapes and sizes on a buff ground color. The underparts are generally light and unspotted. The long neck is maned with short

                                  hair, and the tail has a terminal tuft.  

Dental Formula: 0/3 I, 0/1 C, 3/3 PM, 3/3 M = 32 total. The lower canine teeth are peculiarly flattened and are deeply grooved at right angles to the plane of

                              flattening.  

Diet: Browser largely on acacia, mimosa, and wild apricot trees. It can be supplemented by climbers, vines, and some herbs. Flowers, seed pods, and fruits

          are also eaten in season. Can go without water for long periods of time.  

 

 

 

 

Sources

Nowak, Ronald M. (ed.) 1999.  Walker’s Mammals of the World Vol. 2 (6th edition).  The John Hopkins University Press, Baltimore and London.

Macdonald, David (ed.). 1987.  The Encyclopedia of Mammals.  Facts on File Publications, New York.

Estes, Richard D. 1991.  The Behavior Guide to African Mammals.  The University of California Press, Berkeley.

Kingdon, Jonathan 1997. The Kingdon Field Guide to African Mammals.   Academic Press, London.

Alden, Peter C. et al. 1995. National Audubon Society Field Guide to African Wildlife.  Alfred A. Knopf, Inc., New York.

 

 

 

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