Flawed Methods Seriously Underestimate Projected Extinction Rates... A Hundred-Fold
The more than 16,000 species currently listed by the IUCN as seriously endangered may be gone much sooner than we think. In a new study published in Nature, the University of Colorado's Brett Melbourne and UC Davis' Alan Hastings estimate that endangered species may become extinct 100 times faster than originally expected, blaming earlier predictions on erroneous, outdated models, reports The Guardian's Ian Sample.
It wouldn't be the first time that a previously well-established model has fallen by the wayside in light of stark new evidence (think melting Arctic ice cap). Yet the consequences here could be especially dire: According to Melbourne, certain species "could have months instead of years left" (emphasis mine).Image from JennyHuang
Conservation organizations like the IUCN, whose annual Red List exhaustively catalogues the world's most endangered species, would do well to update their models, the ecologists advise. Species once considered "only" endangered may already be critically endangered -- if not extinct, they warn.
Melbourne and Hastings found that many models simply overlooked factors that could contribute to a species' chances for survival. For instance, random environmental disasters, such as intense heatwaves or storms, are not currently factored into conservationists' calculations. In light of recent history, that looks to be a serious mistake.
The "100 times" number can primarily be attributed to past models' failure to include two key factors: the proportion of males to females in a population and the difference in reproductive success between individuals. The different types of random events these factors could precipitate -- a large swing in the size of a population could cause it to crash, for example -- quickly ratchet up the likelihood that any given species could go extinct.
The only silver lining here is that these findings could help ecologists devise more accurate models, which, in turn, would lead to a much-needed recalibration of conservation groups' objectives.
Image of orangutan from axinar
Via ::Guardian Unlimited: Wildlife extinction rates 'seriously underestimated' (news website)
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