GENEVA (Reuters) -- Colombian spider monkeys, Galapagos snails, unique South African rabbits and one of the world's largest freshwater fish are in stark danger of extinction, a nature body warned on Tuesday.

Also under threat of disappearing in the near future, according to the Swiss-based World Conservation Union (IUCN), are the 21 species of albatross, dozens of types of shark and rayfish and Mediterranean dolphins.

All are among a total of 12,259 varieties of animal, plant and water life described as critically-endangered in this year's version of the IUCN's Red List -- the key reference for biologists tracking the state of the planet's health.

And, according to the inter-governmental organization which works with civil society groups and scientists around the globe, it is largely the fault of humans.

"Places such as the Galapagos, Hawaii and the Seychelles are famed for their beauty, their diversity of plants, animals and ecosystems," said IUCN Director General Achim Steiner, introducing the 2003 list. "But the Red List tells us that human activities are leading to a swathe of extinctions that could make these islands ecologically and aesthetically barren."

The IUCN said studies show that Indonesia, Brazil, China and Peru have the highest number of endangered birds and mammals while plants are most under threat in Ecuador, Malaysia and Sri Lanka as well as in Indonesia and Brazil.

All are countries where industrialization, forest clearance and tourism have developed rapidly in recent decades.

The Red List includes extinctions that have been recorded since the start of the 16th century -- by this year totaling 762.

But biologists say that there are almost certainly hundreds, if not thousands, more as so many species -- especially of the smallest animals, insects and plants -- go unrecorded.