Nature’s backbone at risk
By Martin Fowlie, Wed, 27/10/2010 - 01:00
The most comprehensive assessment of the world’s vertebrates confirms an extinction crisis with one-fifth of species threatened. However, the situation would be worse were it not for current global conservation efforts, according to a study launched at the 10th Conference of the Parties to the Convention on Biological Diversity, CBD, in Nagoya, Japan. The study, published in the international journal Science, used data for 25,000 species from The IUCN Red List of Threatened Species™, to investigate the status of the world’s vertebrates (mammals, birds, amphibians, reptiles and fishes) and how this status has changed over time. The results show that, on average, 50 species of mammal, bird and amphibian move closer to extinction each year due to the impacts of agricultural expansion, logging, over-exploitation, and invasive alien species. “The ‘backbone’ of biodiversity is being eroded”, said the great American ecologist and writer Professor Edward O. Wilson, at Harvard University. “One small step up the Red List is one giant leap forward towards extinction. This is just a small window on the global losses currently taking place.” South-east Asia has experienced the most dramatic recent losses, largely driven by the planting of export crops like oil palm, commercial hardwood timber operations, agricultural conversion to rice paddies, and unsustainable hunting. Parts of Central America, the tropical Andes of South America, and even Australia, have also all experienced marked losses, in particular due to the impact of the deadly chytrid fungus on amphibians. Whilst the study confirms previous reports of continued losses in biodiversity, it is the first to present clear evidence of the positive impact of conservation efforts around the globe. Results show that the status of biodiversity would have declined by at least an additional 20% if conservation action had not been taken. “We know what has to be done to save individual species from extinction”, said Alison Stattersfield, BirdLife’s Head of Science and one of the 12 authors from BirdLife International on the paper. “Through BirdLife’s Preventing Extinctions Programme we are taking effective – and cost-effective - action for the world’s Critically Endangered birds. But much more effort is needed, through NGOs, Governments, businesses and committed individuals working together, to stop the slide towards extinction and start to address the root causes of biodiversity loss.” The study highlights 64 mammal, bird and amphibian species that have improved in status due to successful conservation action. This includes three species that were extinct in the wild and have since been re-introduced back to nature: the California Condor Gymnogyps californianus, and the Black-footed Ferret Mustela nigripes, in the United States, and Przewalski’s Horse Equus ferus, in Mongolia. Conservation efforts have been particularly successful at combatting invasive alien species on islands. The global population of Seychelles Magpie-robin Copsychus sechellarum, increased from fewer than 15 birds in 1965 to 180 in 2006 through control of introduced predators, like Brown Rat Rattus norvegicus, and captive-breeding and re-introduction programmes. On Mauritius, six bird species have undergone recoveries in status, including the Mauritius Kestrel, Falco punctatus, whose population has increased from just four birds in 1974 to nearly 1,000.