Citation
Elephant Seal Genetic Variation and the Use of Simulation Models to Investigate Historical Population Bottlenecks
TL;DR
Northern elephant seals bottlenecked to ~20 individuals in 1890s
Documents the severe genetic bottleneck in northern elephant seals, hunted to approximately 20 individuals by 1892. Despite recovery to over 200,000 individuals, the population retains extremely low genetic diversity - lower than expected even from the bottleneck size due to polygynous mating structure.
Demonstrates how unequal contribution to reproduction reduces effective population size below census size, directly applicable to organizations where a few key decision-makers have outsized influence despite large headcounts.
Key Findings from Hoelzel & al. (1993)
- Northern elephant seals bottlenecked to ~20 individuals in 1890s
- Despite recovery to 200,000+, genetic diversity remains extremely low
- Polygynous mating structure further reduced effective population size