White Rhinoceroses

WHITE RHINOCEROSES, Ceratotherium simum

Images of Rhinoceroses

SUBSPECIES
Northern white rhino, Ceratotherium simum cottonien (endangered)
Southern white rhino, Ceratotherium simum simum

WHAT IT IS


A gentle giant, the biggest land mammal after elephants (though outweighed by hippo). Almost double the weight of a black rhino, with pronounced shoulder hump. Male wt 4488-4972 lb (2040-2260 kg), ht 68-73 in (171-186 cm); Female wt 3520 lb (1600 kg), ht approximately 2 in shorter. Head: massive with wide, square mouth, big ears. Horns: front horn average 24 in (60 cm), longer but thinner in female; back horn much shorter, more triangular. Color: slate gray to yellow-brown.
Massive creatures with barrel-shaped bodies, supported on pillarlike limbs and 3-toed hooves. Head: big and weighty, with small, low-set eyes; prominent, highly mobile ears, and 2 medial horns on the snout. HOTns: grow from the skin, consist of keratin (like hooves, nails, hair), and are unattached to skull. Teeth: no front teeth (incisors); cheek teeth high, broad, and strongly serrated. Skin: thick and creased at junctions, hairless except for fringed ears and tail bristles, plain gray to dark brown. Penis: recurved to rear and testes internal. Scent glands: possible preputial gland in white rhino. Teats:. 2.

WHERE IT LIVES


Formerly widespread in Northern Savanna west of White Nile and Southern Savanna south of the Zambezi. Open habitat and unaggressive nature made it especially vulnerable to human predation. In decline for several hundred years, southern race was wiped out in last century except for a few hundred in Natal. Saved by effective protection and management in Umfolozi-Hluhluwe GP, surplus has been reintroduced over much of its former southern range. Several thousand strong, it now outnumbers the black rhino. But the northern white rhino has gone-except for a couple dozen survivors in Zaire's Garamba NP.

GOOD PLACES TO SEE IT


Umfolozi GR, Kruger NP, South Africa; Hwange NP, Zimbabwe; Garamba NP, Zaire.

ECOLOGY


A savanna form whose preferred habitat includes grassland with trees, water, and mud wallows. Perhaps the largest pure grazer that ever lived, the white rhino uses its wide mouth and muscular lips to graze a broad swath, feeding most efficiently in dense swards of short, green grass. Able to go 2 to 4 days without drinking, even in the dry season, but often drinks twice a day when water nearby.

ACTIVITY


Leaving aside seasonal, daily, and individual variations, white rhinos spend about 1/2 of a 24-hr day feeding, 1/3 resting, and the balance in walking, standing alert, wallowing, drinking, and socializing.

SOCIAL/MATING SYSTEM


The white rhino is the most sociable member of its family, largely because grazers can feed closer together than browsers and frequent open habitats. White rhinos in the main Natal reserves are also crowded, with over 12.5 animals/mi square (5/km square), 3 times the density of the associated black rhino.
While females and young associate in groups, adult males are territorial and essentially solitary. They seek out cows to check their reproductive status and stick around only long enough to mate with any coming into heat. However, some territories include 2 and even 3 or 4 resident adult bulls, all but one of which turn out to be satellites that are tolerated as long as they kowtow to the owner. Since this situation occurs in fenced reserves where there are enough territories (200-600 acres [80-260 ha] in extent) for only two-thirds of the mature bulls, the arrangement may not be natural or normal.
Females and subadults are rarely alone. Cows in Umfulozi GR live in overlapping home ranges of 198 to 642 acres (80-260 ha), which take in 6 to 7 territories.
Females are accompanied by their latest calf and often I or more unrelated juveniles whose own maternal ties ended abruptly after the birth of a new calf. Calfless cows associate in pairs and are especially tolerant of waits; a couple may live with juveniles, which like to associate with peers of the same sex and age, in stable herds of up to 6 rhinos. Larger groups of up to a dozen are only temporary and likely to occur at midday when white rhinos converge on ridges to sleep in a cooling breeze.

HOW IT MOVES


A high-stepping trot is normally the fastest gait, timed at 18 mph (29 kph), which a rhino can maintain for at least 2 mi (5 km). White rhinos can gallop 25 mph (40 kph).

REPRODUCTION


OFFSPRING AND MATERNAL CARE


Cows seek dense cover before calving, remain secluded several weeks before resuming accustomed home range and routine. Calves stand within an hour but remain unsteady for a couple days, They nurse 2 to 3 minutes on demand, begin grazing at 2 months, are weaned at 1 year.

PREDATORS


Newborns weigh only 143 lb, equal to 4% of mother's weight. Mothers are equipped to protect them against all predators but one.

DIFFERENCES IN WHITE RHINO BEHAVIOR


Expect to see and hear Usual context and meaning

Territorial Advertising


Dunging ceremony. Territorial males maintain 20-30 middens, which are also used by all passing white rhinos, but without kicking.
Urine-spraying: Male first horn-wipes bush or ground, then scrapes with all feet before spraying. Performed only by territorial males, on own property, approximately 10 times/hr during boundary patrols.
Scrape-marking, as above but without spraying. Patrolling territorial males scrape-mark every 30 yd or so, especially along boundaries.

Aggression


MAINLY BY TERRITORIAL MALES
Approach in erect posture, head raised, ears cocked. Territorial males accost all passing rhinos, approach within smelling and viewing distance before deciding how to deal with them.
Confrontations. Standing in this position, territorial male may simply silently stare or behave aggressively, depending on identity of intruder. All but territorial neighbors display active submission. As neighbors cannot afford to, they have to back away and defend themselves until off rival's property.
OTHER ACTIONS ASSOCIATED WITH THREAT DISPLAYS
Wiping horn on ground.
Head-low posture with ears back, combined with snarl threats and shrieking if attacked.

Sociable Behavior


Panting. Contact call common in groups and between mother and offspring.

Courtship


MALE BEHAVIOR
Keeping beyond distance at which female behaves aggressively, gives hicthrobbing call during approach
Blocking path or chasing while squealing or loud-wailing if female tries to leave territory. Male shows remarkable restraint during extended courtship.
FEMALE BEHAVIOR
Curls tail and assumes rigid stance during half-hour copulation.

Play


Social play: hom-wrestling matches ± prancing and head-tossing. Mostly by juveniles and adolescents, sometimes cows, usually involving members of different groups.

Response to Predators


Mutual defense: group members stand nimp-to-rump facing outward.
Calves run in front of mother during flight.

Reprinted from "The Safari Companion" by Richard Estes
nature@nature-wildlife.com