Earlier this month (on July 3, 2008) —Science Daily and Nature magazine reported that extinction risks for natural populations of endangered species are "likely being underestimated" by as much as 100-fold because of a mathematical "misdiagnosis"--this based upon a University of Colorado at Boulder researcher.
A new mathematical model was used that accounted for variations in male-to-female sex ratios as well as size or behavioral variations between individuals. These factors can affect survival rates and reproductive success.
"When we apply our new mathematical model to species extinction rates, it shows that things are worse than we thought," said the study author.
For some large endangered species like mountain gorillas, biologists can collect data on specific individuals to help develop and track extinction trajectories. "but for many other species, like stocks of marine fish, the best biologists can do is to measure abundances and population fluctuations, and it's these species that seem ripe for misdiagnosis.
According to a 2007 report by the International Union for Conservation of Nature, a network of about 1,000 organizations with thousands of participating scientists, more than 16,000 species worldwide are threatened with extinction. One in four mammal species, one in eight bird species and one in three amphibian species are on the IUCN "Red List," indicating they are threatened with extinction. Red list: http://www.iucn.org/themes/ssc/red_list_2004/GSA_book/Red_List_2004_exec_summary.pdf
The National Science Foundation funded the Colorado study.