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Extinction crisis getting worse says IUCNPosted: 02 May 2006
The 2006 IUCN Red List of Threatened Species of plants and animals, published today, brings into sharp focus the ongoing decline of the earth�s biodiversity and the impact mankind is having upon life on earth. The number of known threatened species reaches 16,119, while the ranks of those facing extinction are joined by familiar species like the polar bear, hippopotamus and desert gazelles; together with ocean sharks, freshwater fish and Mediterranean flowers.
The Red List shows that the total number of species declared officially Extinct is 784. A further 65 are only found in captivity or cultivation. Meanwhile, IUCN says that positive conservation action has helped the white-tailed eagle and offers a glimmer of hope to Indian vultures.
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The Blue Poison Frog (Dendrobates azureus) is listed as Vulnerable because of its highly restricted range. This frog is known only from the type locality on Vier Gebroeders Mountain, Suriname. It is not significantly threatened in its tiny range, but fire probably has an impact on its forest habitat. Illegal collection of the species for the international pet trade probably no longer has a significant impact, since the species is extensively bred in captivity.
� Russ Mittermeier
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Of the 40,177 species assessed using the IUCN Red List criteria, 16,119 are now listed as threatened with extinction. This includes one in three amphibians and a quarter of the world�s coniferous trees, on top of the one in eight birds and one in four mammals known to be in jeopardy.
Widely recognised as the most authoritative assessment of the global status of plants and animals, it provides an accurate measure of progress, or lack of it, in achieving the globally agreed target to significantly reduce the current rate of biodiversity loss by 2010.
�The 2006 IUCN Red List shows a clear trend: biodiversity loss is increasing, not slowing down,� said Achim Steiner, Director General of the World Conservation Union (IUCN). �The implications of this trend for the productivity and resilience of ecosystems and the lives and livelihoods of billions of people who depend on them are far-reaching. Reversing this trend is possible, as numerous conservation success stories have proven. To succeed on a global scale, we need new alliances across all sectors of society. Biodiversity cannot be saved by environmentalists alone � it must become the responsibility of everyone with the power and resources to act,� he added.
Melting icecaps �
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The Polar Bear (Ursus maritimus) moved into the threatened categories after being reassessed as Vulnerable for the 2006 Red List. Scientists believe its population will reduce by at least 30 per cent over the next 45 years as a result of habitat loss owing to melting sea ice, pollution and declining habitat quality.
� Robert & Carolyn Buchanan.
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Polar bears (Ursus maritimus) are set to become one of the most notable casualties of global warming. The impact of climate change is increasingly felt in polar regions, where summer sea ice is expected to decrease by 50-100 per cent over the next 50-100 years. Dependent upon Arctic ice-floes for hunting seals and highly specialized for life in the Arctic marine environment, polar bears are predicted to suffer more than a 30 per cent population decline in the next 45 years. Previously listed by IUCN as a conservation dependent species, the polar bear moves into the threatened categories and has been classified as Vulnerable. (See note below on Red List threat categories).
Dying deserts
Humankind�s global footprint on the planet extends even to regions that would appear to be far removed from human influence. Deserts and drylands may appear relatively untouched, but their specially adapted animals and plants are also some of the rarest and most threatened. Slowly but surely deserts are being emptied of their diverse and specialized wildlife, almost unnoticed, says IUCN.
The main threat to desert wildlife is unregulated hunting followed by habitat degradation. The dama gazelle (Gazella dama) of the Sahara, already listed as Endangered in 2004, has suffered an 80 per cent crash in numbers over the past 10 years because of uncontrolled hunting parties, and has been upgraded to Critically Endangered. Other Saharan gazelle species are also threatened and they seem destined to suffer the fate of the scimitar-horned oryx (Oryx dammah) and become Extinct in the Wild.
Asian antelopes face similar pressures. The goitered gazelle (Gazella subgutturosa) is widespread across the deserts and semi-deserts of central Asia and the Middle East and until a few years ago had substantial populations in Kazakhstan and Mongolia. Both countries have seen sharp declines because of habitat loss and illegal hunting for meat. The gazelle has been reclassified from Near Threatened to Vulnerable.
Empty oceans
A key addition to the 2006 Red List of Threatened Species is the first comprehensive regional assessment of selected marine groups.
Sharks and rays are among the first marine groups to be systematically assessed, and of the 547 species listed, 20 per cent are threatened with extinction. This confirms suspicions that these mainly slow-growing species are exceptionally susceptible to over-fishing and are disappearing at an unprecedented rate across the globe.
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The Angel Shark (Squatina squatina) was uplisted from Vulnerable to Critically Endangered in 2006 and has been declared extinct in the North Sea. This large angel shark was a common and important demersal predator in the Northeast Atlantic, Mediterranean and Black Seas. Its abundance has declined dramatically during the past 50 years and it is now extremely uncommon throughout most its remaining range. The species is highly vulnerable to bycatch in benthic trawls, set nets and bottom longlines that now operate through most of its range.
� Simon Rogerson.
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The plight of the angel shark (Squatina squatina) and common skate (Dipturus batis), once familiar sights in European fish-markets, illustrates dramatically the recent rapid deterioration of many sharks and rays. They have all but disappeared from sale. The angel shark (upgraded from Vulnerable to Critically Endangered) has been declared extinct in the North Sea and the common skate (upgraded from Endangered to Critically Endangered) is now very scarce in the Irish Sea and southern North Sea.
As fisheries extend into ever deeper waters, the deep bottom-dwelling gulper shark (Centrophorus granulosus) is listed as Vulnerable with local population declines of up to 95 per cent. This fishing pressure, for its meat and rich liver oil, is well beyond their reproductive capacity and sustainable fishing. Populations are destined to decline in the absence of international catch limits.
�Marine species are proving to be just as much at risk of extinction as their land-based counterparts: the desperate situation of many sharks and rays is just the tip of the iceberg,� said Craig Hilton-Taylor of the IUCN Red List Unit. �It is critical that urgent action to greatly improve management practices and implement conservation measures, such as agreed non-fishing areas, enforced mesh-size regulations and international catch limits, is taken before it is too late.�
Freshwater fish
Freshwater species are not faring any better. They have suffered some of the most dramatic declines: 56 per cent of the 252 endemic freshwater Mediterranean fish are threatened with extinction, the highest proportion of any regional freshwater fish assessment so far. Seven species, including carp relatives Alburnus akili in Turkey and Telestes ukliva from Croatia, are now Extinct. Of the 564 dragonfly and damselfly species so far assessed, nearly one in three (174) are threatened, including nearly 40 per cent of endemic Sri Lankan dragonflies.
�We need fish for food, but human activities in watersheds, through forest clearance, pollution, water abstraction and eutrophication are major factors influencing water quality and quantity. This has a major impact on freshwater species, and in turn on the wellbeing of riparian communities,� said Dr Jean-Christophe Vi�, Deputy Coordinator, IUCN Species Programme.
In East Africa, human impacts on the freshwater environment threaten over one in four freshwater fish. This could have major commercial and dietary consequences for the region. For example, in Malawi, 70 per cent of animal protein consumed comes from freshwater fish. The lake trout or Mpasa (Opsaridium microlepis) from Lake Malawi is fished heavily during its spawning runs upriver but has suffered a 50 per cent decline in the past ten years, due to siltation of its spawning grounds and reduced flows due to water abstraction. It is now listed as Endangered.
As well as being an important source of food, freshwater ecosystems are essential for clean drinking water and sanitation. Over a billion people worldwide still do not have access to safe water. The continuing decline in wetlands and freshwater ecosystems will make it increasingly difficult to address this need and maintain existing supplies.
With their semi-aquatic habitat, dragonflies are proving to be useful indicators of habitat quality above and below the water surface. In the densely populated Kenyan highlands, where many rivers originate, the Endangered dragonfly Notogomphus maathaiae of mountain forest streams is being promoted as a flagship species to create awareness for their potential as �guardians of the watershed�. Protecting its riverside forests will also help the farmers of the foothills, by guaranteeing soil stability and a steady flow of water. It is very appropriate that this dragonfly has been named in honour of African Nobel Prize winner Wangari Maathai, a tireless campaigner for the protection of the world�s natural resources in the fight against poverty.
Vulnerable hippos
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The Common Hippopotamus (Hippopotamus amphibius) was uplisted from Least Concern to Vulnerable for the 2006 Red List. The most recent population estimates suggest that there has been 7.20 per cent decline in common hippo populations since 1994. The primary threats to the species are hunting for meat and ivory (found in the canine teeth) and habitat loss.
� Jean-Christophe Vi�.
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Larger freshwater species, such as the common hippopotamus (Hippopotamus amphibius) are also in difficulty. One of Africa�s best known aquatic icons, it has been listed as threatened for the first time and is now classified as Vulnerable, primarily because of a catastrophic decline in the Democratic Republic of the Congo (DRC). In 1994 the DRC had the second largest population in Africa � 30,000 after Zambia�s 40,000 - but numbers have plummeted by 95 per cent. The decline is due to unregulated hunting for meat and the ivory of their teeth.
�Regional conflicts and political instability in some African countries have created hardship for many of the region�s inhabitants and the impact on wildlife has been equally devastating,� said Jeffrey McNeely, IUCN Chief Scientist.
Another casualty of political instability and unrest is the much less well known pygmy hippo (Hexaprotodon liberiensis), restricted to only a handful of West African countries. This shy forest animal was already classified as Vulnerable, but illegal logging and the inability to enforce protection in core areas has pushed it into ever decreasing fragments of forest. It is now classified in the higher threat category Endangered.
Mediterranean plants
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Femeniasia balearica is a Critically Endangered woody perennial shrub endemic to the Balearic Islands, Spain. It now grows only in six sites in the north of the island of Minorca, with fewer than 2,200 individuals remaining. Building and road construction threaten the species, although these activities may also create opportunities for colonisation. This plant is often removed from beach paths because of its spines. It has also been observed that in some years the activities of wood-eating beetles (Oxythrea funesta and Tropinota hirta) appear to reduce seed germination.
� HerbaiVirtual de les Illes Barears.
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The 2006 Red List includes additional species from the Mediterranean region, one of the world�s 34 biodiversity hotspots with nearly 25,000 species of plants � of which 60 per cent are found nowhere else in the world. In the Mediterranean, the pressures from urbanization, mass tourism and intensive agriculture have pushed more and more native species, like the bugloss Anchusa crispa and centuary Femeniasia balearica(both Critically Endangered) towards extinction. The bugloss is only known from 20 small sites and less than 2,200 mature centaury plants remain.
Wake-up call
But what can be done to halt and reverse the decline of the Earth�s biodiversity on which so much of our own well-being depends?
The Red List acts as a wake-up call to the world by focusing attention on the state of our natural environment. In addition to being the most reputable science-based decision-making tool for species conservation on a global scale, it is being more widely adopted at the national level. At least 57 countries now use national Red Lists, following IUCN criteria to focus their conservation priorities.
Thanks to conservation action, the status of certain species has improved: proof, says IUCN, that conservation does work.
Following large recoveries in many European countries, the numbers of white-tailed eagles (Haliaeetus albicilla) doubled in the 1990s and it has been downlisted from Near Threatened to Least Concern. Enforcement of legislation to protect the species from being killed, and protective measures to address threats from habitat changes and pollution have resulted in increasing populations.
On Australia�s Christmas Island, the seabird Abbott�s booby (Papasula abbotti) was declining due to habitat clearance and an introduced invasive alien species, the yellow crazy ant (Anoplolepis gracilipes), which had a major impact on the island�s ecology. The booby, listed as Critically Endangered in 2004, is recovering thanks to conservation measures and has now moved down a category to Endangered.
Other plants and animals highlighted in previous Red List announcements are now the focus of concerted conservation actions, which should lead to an improvement in their conservation status in the near future.
The 300 kg Mekong Catfish (Pangasianodon gigas) of South-east Asia is one of the largest freshwater fish in the world and was listed as Critically Endangered in 2003. Adopted as one of four flagship species by the Mekong Wetlands Biodiversity and Sustainable Use Programme, it is the focus of regional co-operation on fisheries management issues and conservation activities.
Swift action since the dramatic 97 per cent population crash of the Indian Vulture (Gyps indicus), listed as Critically Endangered in 2002, means that the future for this and related species is more secure. The veterinary drug that unintentionally poisoned them, diclofenac, is now banned in India. A promising substitute has been found and captive breeding assurance colonies will be used for a re-introduction programme.
Many other species, such as the humphead wrasse (Cheilinus undulatus) (listed as Endangered since 2004), Saiga antelope (Saiga tatarica) (listed as Critically Endangered since 2002) are also the subject of concerted conservation campaigns.
�These examples show that conservation measures are making a difference,� concluded Achim Steiner. �What we need is more of them. Conservation successes document that we should not be passive by-standers in the unfolding tragedy of biodiversity loss and species extinction. IUCN together with the many actors in the global conservation community will continue to advocate greater investments in biodiversity and to mobilize new coalitions across all sectors of society.�
Building blocks
- Commenting on the report, Dr Susan Lieberman, Director of WWF's Global Species Programmes said:
"This is not just about more and more individual species being threatened by extinction. One by one, the building blocks of entire ecosystems are disappearing. It's like taking one brick after another from a wall, and eventually it will crumble."
"It is not an exaggeration to call today's analysis the reflection of a global conservation crisis."
Climate change represents one of the most pervasive threats to our planet's biodiversity, WWF added. A recently published study co-authored by the conservation organisation suggests that a quarter of the world's species will be on their way to extinction by 2050 as a result of global warming
"It isn't just polar bears and penguins that we must worry about anymore," said Jennifer Morgan, Director of WWF's Global Climate Change Programme. "If the regions with the largest variety of animals and plants are no longer habitable due to global warming then we will destroy the last sanctuaries of many species and at the same time risk the future of millions of people."
Note: The IUCN Red List threat categories are the following, in descending order of threat:
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Extinct or Extinct in the Wild;
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Critically Endangered, Endangered and Vulnerable: species threatened with global extinction;
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Near Threatened: species close to the threatened thresholds or that would be threatened without ongoing specific conservation measures;
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Least Concern: species evaluated with a low risk of extinction;
- Data Deficient: no evaluation because of insufficient data.
Related links:
Getting the measure of extinction
IUCN
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