The last four northern white rhinoceros remaining in the wild are feared to have been killed for their horns by poachers and are now believed to be extinct in the wild. Only a few are left in captivity but they are difficult to breed and the number is so low that the species is regarded as biologically unviable.

The outlook for other types of rhino, including the endangered African black rhino, was more optimistic yesterday however. Figures released by the IUCN, the international conservation body that assesses threats to wildlife, showed that the number of wild rhinos had increased to its highest level for decades.

The northern white rhino, Ceratotherium simum cottoni, has been struggling for suvival since the 1970s, when numbers dropped from about 500 to 15. A slight recovery was recorded in 2003 when 30 were counted but by 2006 only four were left. All of them were recorded in the Garamba National Park in the Democratic Republic of Congo but war and civil unrest in the region has led to an increase in poachers.

“Worryingly, recent fieldwork has so far failed to find any presence of these four remaining rhinos,” Dr Martin Brooks, a rhino specialist with the IUCN, said. “Unless animals are found during the intensive surveys that are planned under the direction of the African Parks Foundation the subspecies may be doomed to extinction.”

Times Archive, 1949: A white rhino cub

My old friend and brother officer captured a white rhino cub up country in Kenya in 1907 or 1908, after he had shot the mother

The southern white rhino, Ceratotherium simum simum, is doing better than its northern counterpart – its numbers have risen from 14,540 in 2005 to 17,480 in 2007.

Conservationists were relieved at the figures for the African black rhino, Diceros bicornis. Recorded numbers rose from 3,730 in 2005 to 4,180 in 2007. Its prospects have been helped by the establishment of several groups, such as the one in North Luangwa National Park, Zambia.

“This is fantastic news for the African black rhino,” said Dr Richard Emslie, of the IUCN species survival commission’s African rhino specialist group. “However, these magnificent creatures are not out of the woods yet. They are still classed as critically endangered and face increasing threats of poaching and civil unrest. There is no room for complacency.”

Most African black rhino are found in Zimbabwe, South Africa, Namibia and Kenya but increasingly they are being found in neighbouring countries as the animals expand their range. Of the four countries, only Zimbabwe experienced a fall in the rhino population since 2005.

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