July 08, 2002
JOHANNESBURG: Zoologists have a little tale to tell about rhinos.
It seems these intimidating beasts take companionship seriously,
with most of them forming pairs that are mutually helpful. No other
animal has been observed to form buddy pairs in this way, says Ron
Swaisgood, who studies animal behaviour at San Diego Zoo in California.
"It's an incredibly original and creative idea," Swaisgood
is quoted in a report in Nature. Adrian Shrader, an expert marksman,
fires tranquillizers from a helicopter into the animal's hide. Game-catchers
swoop in on the felled beast and implant a radio-transmitter deep
in its horn.
Shrader used the radio signals to track rhino in South Africa's
vast Hluhluwe-Umfolozi Park, an 896 square-kilometre reserve in
KwaZulu-Natal. Now, after two years' trailing, he has made a surprising
discovery: that the beasts like companionship. When rhinos venture
into new parts of the reserve, "they do it with a buddy",
says Shrader, one that already knows the territory.
Going alone to a new place is hard work, says Swaisgood -- as every
tourist knows, a friend can help you find the best watering holes
and avoid the dangerous neighbourhoods. Similarly, white rhino buddies
may help find food, water and avoid predators' lairs. "It makes
intuitive sense to pair up and check it out," says Swaisgood.
In the early 1900s, there were fewer than 50 southern white rhino.
There are now more than 12,000 in the wild, thanks in part to successful
animal management in the Hluhluwe-Umfolozi Park.
"It's one of the great conservation success stories,"
says Shrader. When the reserve reaches its rhino capacity, the surplus
animals are removed from particular spots and shipped to zoos and
Remaining rhino were known to disperse into the 'vacuum zones' from
which previous occupants had been removed - but it was unclear what
made them move. Shrader observed that teenage rhino, who spend up
to 12 years a-roaming after leaving their mothers, form alliances
with fellow-rhinos during that time lasting days or years. Eventually,
they choose a territory to settle in, the report said.
Following buddies "explains how rhino are finding these man-made
areas", says Shrader. The findings could strengthen rhino management
programmes by highlighting the importance of keeping a few animals
in the empty zones to help dispersal. And animals sent elsewhere
in the world could be allowed to get to know potential buddies through
a fence before they are released, suggests Swaisgood.