How many grizzlies live in the Northern Continental Divide ecoystem (that’s Glacier National Park and about 6-million adjaccent acres)?
A massive first-of-its-kind DNA study was undertaken several years ago using this new method which avoids the pitfalls of direct observation plus interpolation which has been the past method.
The Daily InterLake reports today the number is a minimum of 545 grizzlies.
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Ralph Maughan
Dr. Ralph Maughan is professor emeritus of political science at Idaho State University with specialties in natural resource politics, public opinion, interest groups, political parties, voting and elections. Aside from academic publications, he is author or co-author of three hiking/backpacking guides, and he is President of the Western Watersheds Project.
I have a question regarding grizzly numbers
A new method to estimate population size is now used in GYE. And populations rises from 31 to 52. See
http://www.jacksonholenews.com/article.php?art_id=1032
Does someone know the details of the statistical methods ? Is the method publicly available ?
read more
“But since then, Schwartz says he’s found a better way to count. The previous population estimates, he says, did not account for “background noise” that causes sharp upswings in yearly totals of females with cubs of the year. The old counting method, he says, also caused statisticians to cringe.”
“With the new method, math takes all of the numbers of females with cubs and smooths that line in a way that is acceptable to the statisticians,” he said. With updated calculation, last year’s count came it at 52, not 31. “It will be more consistent from year to year to year,” Schwartz said.
I don’t know the answer to the question you ask, but I did get this related info from a listserv today:
“It appears that the full population estimate plus its 95% confidence interval will be in the range of 650-800.”
So 545 bears must be at least 3 confidence intervals toward the tail of the estimate.