Under current assumptions we are slowly entering a period of major biodiversity loss with threats to the planet that are severe but difficult to perceive. The effects of human actions on the Earth’s ecosystem are well documented, but what if the scale and pace of species extinction and its consequences have been grossly underestimated? Almost daily reports of severely threatened or extinct species should serve as a wake-up call. But focusing exclusively on species extinction inaccurately reflects the magnitude of…
The list of other disappearing groups is growing. In the last 500 years 187 species have become extinct, 90 per cent of which were insular species, says the study. The new approach confirms 80 per cent of the current IUCN Red List and reclassifies nine species. Eight of them, including three birds, the poo-uli, the Pernambuco pygmy-owl and the cryptic treehunter, are added to the growing list of confirmed or near extinctions. But not only birds are in danger of dying out. The list of other disappearing animals is also rapidly growing. At least 1,000 vertebrate species have become extinct in the last 5 centuries. And the latest Red List assessment indicates that more than 26,000 of the world’s species are now endangered. According to scientists our actions are a key factor in this so-called sixth mass extinction.
Falling Walls: Gerardo, most extinctions have occurred on islands until recently. The Spix’s macow now seems to be extinct in Brazil and the extinction crisis is also unfolding in large countries – why?
Gerardo Ceballos: Until recently most extinctions have occurred on islands, because they are small and species with small populations are more prone to extinctions. Now, extinctions are occurring on continents too, and my study on population extinctions indicates that this extinction crisis is unfolding on continents due to human activities: Habitat loss and fragmentation, illegal trade an overexploitation, pollution, invasive species and climate change are some of the main factors. Ecosystems are being destroyed to plant crops such as soy and oil palms, and to cattle grazing.
Falling Walls: How many of the world species are threatened?
Gerardo Ceballos: The most recent evaluation indicates that some 30% of all species are endangered. IUCN has analysed population trends of 91.000 species and found out that 26,000 are threatened (27%). We found out that 32% of 27,600 vertebrates have declining populations. So, both population and species extinction are accelerating.