Title

Case Study of a Population Bottleneck: Lions of the Ngorongoro Crater

Authors

Craig Packer, University of Minnesota - Minneapolis
A. E. Pusey, University of Minnesota - Minneapolis
H. Rowley, University of Minnesota - Minneapolis
D. A. Gilbert, National Cancer Institute at Frederick
Janice S. Martenson, National Cancer Institute at Frederick
Stephen J. O'Brien, National Cancer Institute at FrederickFollow

Document Type

Article

Publication Date

6-1991

Publication Title

Conservation Biology

ISSN

0888-8892

Volume

5

Issue/No.

2

First Page

219

Last Page

230

Abstract

Lions in the Ngorongoro Crater, Tanzania, form a small and naturally isolated population In 1962, the Crater lions suffered an epizootic that reduced the population to nine females arui one male. An additional seven males apparently immigrated into the Crater in 1964-1965. but there has been no further immigration into the Crater in the past 25 years. By 1975, the population had recovered to its current level of 75—125 animals. All members of the current Crater population are descended from only 15 founders, and over the years there has been considerable variance in the reproductive success of both sexes. The Crater was probably colonized by lions from the nearby Serengeti ecosystem and the contemporary Crater lion population shows a significant lack of genetic diversity compared to the much larger Serengeti population The detailed reproductive history of the Crater population was incorporated into a series of stochastic computer simulations that generated distributions of expected allele frequencies under different sets of initial conditions. The simulations suggest that the Crater population may have passed through previous bottlenecks before 1962 but that the level of heterozygosity in the breeding population has been declining since the mid-1970s, regardless of the population's genetic composition in the 1960s. High levels of inbreeding are correlated with increased levels of sperm abnormality in lions and there is evidence that the reproductive performance of the Crater lions has decreased as a result of decreasing heterozygosity

Comments

©1991 Blackwell Publishing Ltd

Additional Comments

NSF grant #s: 8507087, 8807702

NSUWorks Citation

Packer, Craig; A. E. Pusey; H. Rowley; D. A. Gilbert; Janice S. Martenson; and Stephen J. O'Brien. 1991. "Case Study of a Population Bottleneck: Lions of the Ngorongoro Crater." Conservation Biology 5, (2): 219-230. https://nsuworks.nova.edu/cnso_bio_facarticles/328

ORCID ID

0000-0001-7353-8301

ResearcherID

N-1726-2015