Giraffe numbers have fallen off by as much as 40 percent since the 1980s. The Red List rated the giraffe "vulnerable" to extinction on current trends for the first time, against a previous rating of "least concern."
Giraffes are threatened by illegal hunting, civil unrest, mines and expanding farms, according to the non-governmental organization the Red List.
The Switzerland-based NGO reported that that the populations of the world's tallest land creature fell to about 98,000 from an estimated 152,000-163,000 in 1985. Less than 98,000 giraffes remain in Africa.
This "silent extinction" is being driven by illegal hunting and an expansion of farmland in Africa, the International Union for Conservation of Nature (IUCN) - which compiled the list - wrote.
"Whilst giraffes are commonly seen on safari, in the media and in zoos, people - including conservationists - are unaware that these majestic animals are undergoing a silent extinction," Julian Fennessy, an IUCN giraffe specialist, said in a statement.
Expansion of farmland
Giraffes are at risk from the expansion of farmland to feed a rising human population and from killings for their meat, according to the IUCN.
"People are competing for fewer and fewer resources and the animals are worse off ... especially with civil strife," Craig Hilton-Taylor, head of the Red List, told the news agency Reuters. Drought and climate change are aggravating factors, he added.
Among other changes on the list, the African grey parrot - famed for its skill in mimicking human speech - was rated endangered, one step worse than its earlier category as vulnerable.
The list also found that 11 percent of more than 700 other species of bird newly assessed were at risk of extinction, such as the Antioquia wren in Colombia, which is under threat from a hydro-electric dam.
jbh/bw (dpa, Reuters)