More than one fifth of the world’s bird species are under threat and one in eight is struggling for survival, a report says today.

The International Union for the Conservation of Nature and Natural Resources will add 11 species to its “red list” of most threatened species, following the report by BirdLife International, a global alliance of conservation bodies.

The annual evaluation of bird species also added 17 species to the near-threatened category. Overall, 2,033 species are thought to be in danger.

The loss or deterioration of habitat, due to factors such as dams, fishing and cattle numbers, was to blame for the plight of 86 per cent of the 1,221 most threatened species.

BirdLife International said that since the survey was first carried out in 1988 the conservation status of birds has “deteriorated steadily”.

Five species of vultures are nearer extinction, according to the report. The St Helena plover and the waved albatross of the Galápagos islands are also seriously threatened.

There are, however, some bright spots of hope. Mauritius parakeets have been downgraded from critically endangered to endangered because of releases of captive birds, the provision of artificial nest sites and measures to control predators.

However, Alistair Gammell, the international director of the Royal Society for the Protection of Birds, said: “While conservation efforts have been successful in recovering some species, there are more and more species slipping towards extinction every year.”

Over the weekend a Taiwanese campaign group called on conservation groups to lobby their Government over a dam project that will drown more than a thousand acres of forest, home to fairy pitta, Taiwan partridge, Swinhoe’s pheasant and maroon oriole – all threatened species.

Under threat

Spix’s Macaw Thought to have died out in the wild in its native Brazil because of exploitation for the cagebird trade

Waved Albatross Nests only in the Galapágos Islands. Critically endangered because of long line fishing

St Helena Plover Small wading bird. Numbers have declined after the removal of cattle from its habitat, which led to more invasive plant life

Spectacled Petrel Breed only on Inaccessible Island, Tristan da Cunha, a British overseas territory in the South Atlantic

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