Rapid Population Growth of a Critically Endangered Carnivore
M. B. Grenier,1,2*
D. B. McDonald,1
S. W. Buskirk1
Reintroductions of endangered species are controversial because
of high costs and frequent failures. However, the population
of black-footed ferrets descended from animals released in Shirley
Basin, Wyoming, from 1991 to 1994 has grown rapidly after a
decline to a low of five animals in 1997. Beginning around 2000,
the population grew rapidly to an estimated 223 (95% confidence
interval is 192 to 401) individuals in 2006. Matrix population
modeling shows the importance of survival and reproduction during
the first year of life, reflecting an uncommon life history
for an endangered mammalian carnivore. Recovery of the species
may benefit from more opportunistic and widespread releases.
2 Wyoming Game and Fish Department, 260 Buena Vista Drive, Lander, WY 82520, USA.
* To whom correspondence should be addressed. E-mail: martin.grenier{at}wgf.state.wy.us
