A New Warning for Earth's Biodiversity

GLAND, Switzerland, November 18, 2003 (ENS) - The latest assessment of the world's endangered plant and animal species paints a stark picture of rapidly declining biodiversity across the planet. Although scientists have only scratched the surface of assessing all known plant and animal life on Earth, 12,259 species are known to be threatened with extinction, according to the 2003 Red List of Endangered Species released today by the World Conservation Union (IUCN).

Based on information from a network of 7,000 experts and data from a number of partner organizations, the IUCN Red List is the world's most authoritative inventory of the conservation status of plants and animals.

It provides the "best available knowledge necessary for sound conservation action," according to IUCN Director General Achim Steiner.

The world needs to find the "political will and resources to stem the loss of biodiversity," Steiner said, but the Red List provides daunting evidence that stemming this tide will require a monumental effort.

The main threat to the planet's biodiversity is not difficult to identify - humans.

Human activity has pushed 820 species to extinction or extinction in the wild in the past 500 years.

The critically endangered yellow breasted capuchin is in Brazil’s Atlantic Forest region. It has a very restricted and highly fragmented range and is also heavily hunted as bushmeat and for use as pets. (Photo by Russell Mittermeier courtesy IUCN)

Habitat loss and degradation affect 89 percent of threatened birds, 83 percent of threatened mammals and 91 percent of threatened plants.

Scientists estimate that the current species extinction rate is between 1,000 and 10,000 times higher than it would naturally be.

Although revisions in taxonomy, new assessments and discoveries make it difficult to compare previous lists to the latest version, there is a clear trend of increasing pressure on the Earth's biological diversity.

This year's inventory contains more than 2,000 new entries compared with the 2002 list.

Some 380 taxa - species, subspecies, etc. - were reassessed for the 2003 list, most upgraded to reflect a greater threat of extinction.

Species threatened with extinction fall into three categories - critically endangered, endangered, or vulnerable.

Many more plant species are now classified as being under threat - new additions to the list include 1,164 Ecuadorian plants, 125 Hawaiian plants, and 303 cycads, which are the oldest seed plants on the planet.

A total of 6,774 plants are considered under threat. This represents some 2 percent of the world's described plants, the IUCN reports, but only 4 percent of those species have been evaluated.

Plants are believed to be declining most rapidly in Brazil, Ecuador, Indonesia, Malaysia and Sri Lanka.

More than 50 percent of cycad species are threatened. (Photo by John S. Donaldson courtesy IUCN)

One in every four mammals and one in every eight birds are facing a high risk of extinction in the near future, with Indonesia, India, Brazil, China and Peru among the countries with the highest number of known threatened birds and mammals.

There are similar trends for reptiles, fish and invertebrates, although the organization acknowledges that these declines are harder to assess because less is known about these taxa.

But a number of amphibian species have shown rapid and unexplained disappearances, in Australia, Costa Rica, Panama, and Puerto Rico.

There are similar indications that freshwater fish species may be suffering a serious deterioration, particularly river dwelling species.

One is example is Asia's Mekong giant catfish, which has been upgraded to critically endangered. The species, which can grow to 3 meters in length and is one of the world's largest freshwater fish, has declined by more than 80 percent over the past 13 years.

The Mekong giant catfish is suffering from overfishing and habitat loss. (Photo by Zeb S. Hogan courtesy IUCN)

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

Forty nine species of Galapagos island snails were assessed or reassessed for the 2003 Red List, with many listed as critically endangered and several believed to already be extinct; invasive species such as goats, pigs and fire ants are mostly responsible.

Continental species are not faring much better.

The IUCN has uplisted South Africa's riverine rabbit to critically endangered and scientists estimate less than 250 breeding pairs remain. Habitat loss and fragmentation, along with predation by feral cats and dogs, is likely to cause further declines in this tiny population.

Three species of neotropical primates have been reassessed to reflect increasing threat of extinction, including the variegated spider monkey. Found only in Columbia and Venezuela, the species is now classified as critically endangered, as is the pied tamarin.

The Mexican black howler monkey has been uplisted to endangered due to a more than 50 percent loss of habitat and a predicted 70 percent decline in population over the next three decades.

The story is sadly similar for the world's marine species, even though they are "widely believed to be resilient to extinction," according to David Brackett, chair of IUCN's Species Survival Commission (SSC).

"They are rapidly proving that they are just as vulnerable as their land based counterparts," Brackett said.

Six species of albatross now face a greater risk of extinction and all 21 species of the marine bird are now on the Red List.

There has been a reduction in the availability of food for the Mediterranean subpopulation of the short beaked common dolphin through a combination of environmental changes, overfishing and habitat degradation. (Photo by Giovanni Bearzi courtesy IUCN)

The IUCN determined that the Northeast Atlantic subpopulation of the spiny dogfish is now endangered, while the Northwest Atlantic subpopulation is rated as vulnerable.

There are a few glimmers of success amid a list dominated by concern. The golden lion tamarin, for example, has been downgraded from critically endangered to endangered. Thirty years of conservation efforts have paid off for the primate species, the IUCN reports, and it demonstrates that humans have the ability to change the fate of endangered species in a positive way.

"Above all, the Red List is a wake up call to all of us," said IUCN/SSC Red List Program Officer Craig Hilton-Taylor says. "By working together we can help conserve what remains of Earth's biodiversity."