Unanimous agreement among scientists: Earth to suffer major loss in species

Jeremy Hance
mongabay.com
November 09, 2011



The thylacine, the dodo, the great auk, the passenger pigeon, the golden toad: these species have become symbols of extinction. But they are only the tip of the recent extinction crisis, and according to a survey of 583 conservation scientists, they are only the beginning. In a new survey in Conservation Biology, 99.5 percent of conservation scientists said a serious loss in biodiversity was either 'likely', 'very likely', or 'virtually certain'. The prediction of a significant loss of species is not surprising—scientists have been warning for decades that if global society continues with business as usual the world will suffer from mass extinction—what is perhaps surprising is the practically unanimous expectation that a global biodiversity decline will occur.

"Understanding the degree of consensus within the scientific community will help policy makers to interpret scientific advice, improving the likelihood of successful of conservation initiatives," said study author Murray Rudd with the University of York. "The extremely high level of consensus demonstrated by these results underlines the urgency of preventing further damage to the natural world."

In addition, nearly 80 percent of respondents agreed that it was 'virtually certain' that human activities were accelerating species loss. Deforestation, habitat loss, climate change, pollution, overexploitation for food or medicine, disease, and invasive species are among a few of the big drivers of biodiversity decline worldwide.

According to the survey, tropical coral reefs are the most likely to see extinctions. Eighty-eight percent of respondents familiar with coral reefs—the most biodiverse marine ecosystems on Earth—predicted that a serious loss was 'very likely' or 'virtually certain'. While coral reefs are suffering from pollution and overfishing, perhaps the most drastic impact is the ongoing rise of greenhouse gas emissions. Ocean acidification from rising carbon levels hurts a coral reef's ability to calcify, imperiling the ecosystem. In addition, rising sea temperatures and sea levels due to climate can cause coral bleaching, which has devastated whole reef systems.

Around half of the researcher (50.3 percent) would like to see criteria laid out for 'conservation triage'. Conservation triage is a controversial idea whereby conservation priorities—much like triage in an emergency room—would be more strictly determined given limited funds and resources. The idea, however, portends that some species would be allowed to go extinct without conservation-efforts because their situation would be perceived as too dire to 'waste' resources.

According to the IUCN Red List, over 19,000 species are currently classified as Vulnerable, Endangered, and Critically Endangered. However the Red List has only had the capacity to date to analyze around 3 percent of the world's known species. Even more alarming no one knows just how many species inhabit Earth with estimates ranging from 3 million to 100 million (currently almost 2 million have been described).



CITATION: Rudd. M. Scientists' Opinions on the Global Status and Management of Biological Diversity. Conservation Biology, Wiley-Blackwell, DOI: 10.1111/j.1523-1739.2011.01772.x



A Gallery of the Critically Endangered

The Sumatran orangutan (Pongo abelii) is considered Critically Endangered with approximately 7,000 left, representing an 80% decline in 75 years. Photo by: Rhett A. Butler.
The Sumatran orangutan (Pongo abelii) is considered Critically Endangered with approximately 7,000 left, representing an 80% decline in 75 years. Photo by: Rhett A. Butler.



A female leather-back sea turtle lays a precarious nest. The world's largest marine turtle in the world, the leather-back is listed as Critically Endangered by the IUCN Red List. Photo by: Tiffany Roufs.
A female leather-back sea turtle lays a precarious nest. The world's largest marine turtle in the world, the leather-back is listed as Critically Endangered by the IUCN Red List. Photo by: Tiffany Roufs.



A black-and-white ruffed lemur (Varecia variegata) feeds on a tamarind in Madagascar. Their population has dropped by 80% in 27 years. This species is also listed as Critically Endangered. Photo by: Rhett A. Butler.
A black-and-white ruffed lemur (Varecia variegata) feeds on a tamarind in Madagascar. Their population has dropped by 80% in 27 years. This species is also listed as Critically Endangered. Photo by: Rhett A. Butler.



Listed as Critically Endangered, the Sumatran rhino (Dicerorhinus sumatrensis) is down to around 250 individuals and is one of the world's rarest mammals. Photo by: Jeremy Hance.
Listed as Critically Endangered, the Sumatran rhino (Dicerorhinus sumatrensis) is down to around 250 individuals and is one of the world's rarest mammals. Photo by: Jeremy Hance.



Native to the Indonesian island of Sulawesi, the black-crested macaque (Macaca nigra) is classified by the IUCN Red List as Critically Endangered. Photo by: Rhett A. Butler.
Native to the Indonesian island of Sulawesi, the black-crested macaque (Macaca nigra) is classified by the IUCN Red List as Critically Endangered. Photo by: Rhett A. Butler.



The blue iguana (Cyclura lewisi) has been helped by conservation efforts going from around 24 individuals to 500, but it is still listed as Critically Endangered. Photo by: Rhett A. Butler.
The blue iguana (Cyclura lewisi) has been helped by conservation efforts going from around 24 individuals to 500, but it is still listed as Critically Endangered. Photo by: Rhett A. Butler.















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CITATION:
Jeremy Hance
mongabay.com (November 09, 2011).

Unanimous agreement among scientists: Earth to suffer major loss in species .

http://news.mongabay.com/2011/1108-hance_survey_extinction.html