1 in 5 invertebrate species threatened with extinction

That is the shocking headline from a report by the IUCN, IUCN Species Survival Commission and the Zoological Society of London, due to be presented at the IUCN World Conservation Congress in Jeju, tomorrow (7th September). ‘Spineless: Status and Trends of the World’s Invertebrates‘ suggests that nearly 20% of invertebrates – which comprise nearly 80 percent of the world’s species – are threatened with extinction.

Scientists reviewed 12,000 invertebrates from the IUCN Red List of Threatened Species to assess the levels of threat facing invertebrates. The results reveal that invertebrates are threatened to the same extent as vertebrates and plants across the globe.

Freshwater invertebrates appear to be the most threatened group of species, at risk due to pollution, for example from agricultural run-off, domestic sewage and industrial waste. Damming, and the consequent effect of this on water quality, also poses a challenge. Across all invertebrate species those which are less mobile and are localised in distribution are threatened to a greater extent than those more mobile. This reflects the levels of threat facing vertebrates: for example, fresh water molluscs are threatened to a similar extent to amphibians (a third of species threatened), whilst those invertebrate and vertebrate species that can shift their range to a greater extent (butterflies, dragonflies, birds) are threatened to a lesser degree (a tenth of species threatened).

The IUCN Species Survival Commission has called for an expansion in the number of invertebrate species assessed, in order to raise the conservation profile of these organisms. For example, only 1% of marine invertebrates (species described) are included in the IUCN Red List of Threatened Species, making an assessment of the threats facing these species (approximately 35% of species threatened) less robust than for other groups.

More from: BBC News – ‘ ‘Spineless’ animals under threat of extinction’, Ella Davies, 31 August 2012