Extinction crisis hits apes, corals, vultures and dolphins

Posted: 15 September 2007

Life on Earth is disappearing fast and will continue to do so unless urgent action is taken, according to the latest review of threatened and endangered species by the World Conservation Union. It adds another 190 species of plants, animals and birds to the Red List of theatened species, including corals for the first time.

There are now 41,415 species on the IUCN Red List and 16,306 of them are threatened with extinction, up from 16,118 last year. The total number of extinct species has reached 785 and a further 65 are only found in captivity or in cultivation.

One in four mammals, one in eight birds, one third of all amphibians and 70 per cent of the world's assessed plants on the 2007 Red List are in jeopardy.

Julia Marton-Lefèvre, Director General of IUCN said: "The rate of biodiversity loss is increasing and we need to act now to significantly reduce it and stave off this global extinction crisis. This can be done, but only with a concerted effort by all levels of society."

Great apes

Western lowland gorilla
Western lowland gorilla
Western lowland gorilla - Critically Endangered. Photo © M. Watson / www.ardea.com
The reassessment of our closest relatives, the great apes, has revealed a grim picture, says IUCN. The Western Gorilla (Gorilla gorilla) has moved from Endangered to Critically Endangered, after the discovery that the main subspecies, the Western Lowland Gorilla (Gorilla gorilla gorilla), has been decimated by the commercial bushmeat trade and the Ebola virus. Their population has declined by more than 60 per cnet over the last 20-25 years, with about one third of the total population found in protected areas killed by the Ebola virus over the last 15 years.

The Sumatran Orangutan (Pongo abelii) remains in the Critically Endangered category and the Bornean Orangutan (Pongo pygmaeus) in the Endangered category. Both are threatened by habitat loss due to illegal and legal logging and forest clearance for palm oil plantations. In Borneo, the area planted with oil palms increased from 2,000 km2 to 27,000 km2 between 1984 and 2003, leaving just 86,000 km2 of habitat available to the species throughout the island.

Galapagos corals

Corals have been assessed and added to the IUCN Red List for the first time. Ten Galapagos species have entered the list, with two in the Critically Endangered category and one in the Vulnerable category. Wellington's Solitary Coral (Rhizopsammia wellingtoni) has been listed as Critically Endangered (Possibly Extinct). The main threats to these species are the effects of El Niño and climate change.

Floreana coral
Floreana coral
Floreana coral (Tubastraea floreana), endemic to the Galápagos Archipelago, is Critically Endangered. Photo © Paul Humann/ www.fishid.com
In addition, 74 seaweeds have been added to the IUCN Red List from the Galapagos Islands. Ten species are listed as Critically Endangered, with six of those highlighted as Possibly Extinct. The cold water species are threatened by climate change and the rise in sea temperature that characterizes El Niño. The seaweeds are also indirectly affected by overfishing, which removes predators from the food chain, resulting in an increase of sea urchins and other herbivores that overgraze these algae.

Yangtze dolphins

After an intensive, but fruitless, search for the Yangtze River Dolphin, or Baiji, (Lipotes vexillifer) last November and December, it has been listed as Critically Endangered (Possibly Extinct). The dolphin has not been placed in a higher category as further surveys are needed before it can be definitively classified as Extinct. A possible sighting reported in late August 2007 is currently being investigated by Chinese scientists. The main threats to the species include fishing, river traffic, pollution and degradation of habitat.

India and Nepal's crocodile, the Gharial (Gavialis gangeticus) is also facing threats from habitat degradation and has moved from Endangered to Critically Endangered. Its population has recently declined by 58 per cent, from 436 breeding adults in 1997 to just 182 in 2006. Dams, irrigation projects, sand mining and artificial embankments have all encroached on its habitat, reducing its domain to 2 per cent of its former range.

Vulture crisis

This year the total number of birds on the IUCN Red List is 9,956 with 1,217 listed as threatened. Vultures in Africa and Asia have declined, with five species reclassified on the IUCN Red List. In Asia, the Red-headed Vulture (Sarcogyps calvus) moved from Near Threatened to Critically Endangered while the Egyptian Vulture (Neophron percnopterus) moved from Least Concern to Endangered. The rapid decline in the birds over the last eight years has been driven by the drug diclofenac, used to treat livestock.

In Africa, three species of vulture have been reclassified, including the White-headed Vulture (Trigonoceps occipitalis), which moved from Least Concern to Vulnerable, the White-backed Vulture (Gyps africanus) and Rüppell's Griffon (Gyps rueppellii), both moved from Least Concern to Near Threatened. The birds' decline has been due to a lack of food, with a reduction in wild grazing mammals, habitat loss and collision with power lines. They have also been poisoned by carcasses deliberately laced with insecticide. The bait is intended to kill livestock predators, such as hyenas, jackals and big cats, but it also kills vultures.

After a major assessment of Mexican and North American reptiles, 723 were added to the IUCN Red List, taking the total to 738 reptiles listed for this region. Of these, 90 are threatened with extinction. Mexico's Santa Catalina Island Rattlesnake (Crotalus catalinensis) has also been added to the list as Critically Endangered, after being persecuted by illegal collectors.

Wild apricot

There are now 12,043 plants on the IUCN Red List, with 8,447 listed as threatened. The Woolly-stalked Begonia (Begonia eiromischa) is the only species to have been declared extinct this year. This Malaysian herb is only known from collections made in 1886 and 1898 on Penang Island. Extensive searches of nearby forests have failed to reveal any specimens in the last 100 years.

The Wild Apricot (Armeniaca vulgaris), from central Asia, has been assessed and added to the IUCN Red List for the first time, classified as Endangered. The species is a direct ancestor of plants that are widely cultivated in many countries around the world, but its population is dwindling as it loses habitat to tourist developments and is exploited for wood, food and genetic material.

Overfishing continues to put pressure on many fish species, as does demand from the aquarium trade. The Banggai Cardinalfish (Pterapogon kauderni), which is highly prized in the aquarium industry, is now 'edangered'. The fish, which is only found in the Banggai Archipelago, near Sulawesi, Indonesia, has been heavily exploited, with approximately 900,000 extracted every year. Conservationists are calling for the fish to be reared in captivity for the aquarium trade, so the wild populations can be left to recover.

Parrot success

These highlights from the 2007 IUCN Red List are examples of the rapid rate of biodiversity loss around the world. This is having a direct impact on people's lives, says IUCN. Fish, for example, deprive rural poor communities not only of their major source of food, but of their livelihoods as well.

Mauritius parakeet
Mauritius parakeet
The Mauritius parakeet (Psittacula eques) has moved from Critically Endangered to Endangered. Photo © Malcolm Burgess
It says conservation action is slowing down biodiversity loss in some cases, but there are still many species that need more attention from conservationists. This year, only one species has moved to a lower category of threat. The Mauritius Echo Parakeet (Psittacula eques), which was one of the world's rarest parrots 15 years ago, has moved from Critically Endangered to Endangered. The improvement is a result of successful conservation action, including close monitoring of nesting sites and supplementary feeding combined with a captive breeding and release programme.

Holly Dublin, Chair of IUCN's Species Survival Commission, said that while conservation networks are working effectively, "much more help and support is needed from the general public, the private sector, governments and policy makers to ensure that global biodiversity remains intact for generations to come."

This view was echoed by Dr Mark Wright, chief scientist at WWF-UK: "We're at code red,"he said. "The plight of the world's species is a mirror on the state of the planet. Species are under enormous pressure as we systematically destroy their habitat or over-exploit them for our increasingly demanding lifestyles. We urgently need to reverse this trend and startliving within the planet's natural resources - not just for the well-being of threatened these species but also for our own."

The total number of species on the planet is unknown; estimates vary between 10 - 100 million, with 15 million species being the most widely accepted figure. 1.7 - 1.8 million species are known today. People, either directly or indirectly, are the main reason for most species' decline. Habitat destruction and degradation continues to be the main cause of species' decline, along with the all too familiar threats of introduced invasive species, unsustainable harvesting, over-hunting, pollution and disease. Climate change is increasingly recognized as a serious threat, which can magnify these dangers

Related links:

Biodiversity: the fabric of life for full coverage of this topic.

IUCN Red List