Lions and leopards are endangered species but robins and raccoons are not but how do we define how many lions would there have to be? Most mammal species have been driven to extinction due to human activities.
When researchers Jeremy T. Bruskotter of Ohio State University, Adam Feltz of University of Oklahoma, and Tom Offer-Westort also of University of Oklahoma launched a survey on "What is an endangered species" -- they soon encountered a far tougher question: How much loss should a species endure before we agree that the species deserves special protection.
They surveyed 1,000 (representatively sampled) Americans after giving them the information in the previous paragraph. The results, "What is an endangered species?: judgments about acceptable risk," are published in Environmental Research Letters.
Three-quarters of those surveyed said a species deserves special protections if it had been driven to extinction from any more than 30% of its historic range. Not everyone was in perfect agreement. Some were more accepting of losses.
Survey on redefining'endangered species'
The survey results indicate that people more accepting of loss were less knowledgeable about the environment and self-identify as advocates for the rights of gun and land owners. Still, three-quarters of people from the group of people who were more accepting of loss thought special protections were warranted if a species had been lost from more than 41% of their former range.
These attitudes of the American public are aligned with the language of the US Endangered Species Act -- the law that defines an endangered species as one that is "in danger of extinction throughout all or a significant portion of its range."
Government decision-makers and scientists tend to say a species is endangered if its risk of total and complete extinction exceeds 5% over 100 years. Before human activities began elevating extinction risk, a typical vertebrate species would have experienced an extinction risk of 1% over a 10,000-year period.
Extinction risk many times greater than real?
The extinction risk that decision-makers and the experts have tended to consider acceptable (5% over 100 years) corresponds to an extinction risk many times greater that the extinction risk we currently impose on biodiversity, said the researchers who conducted the survey.
Experts on endangered species have a better handle on the facts but there is cause for concern when decision-makers do not reflect the broadly held values of their constituents. One reason for this discrepancy in values is the influence of special interests on decision-makers and experts charged with caring for biodiversity.
Getting the answer right is more important. If we do not know well enough what an endangered species is, then we cannot know well enough what it means to conserve nature, because conserving nature is largely about giving special care to endangered species until they no longer deserve that label, wrote researchers.
