Evaluating an icon of population persistence: the Devil's Hole pupfish

Area of Science:

• Ecology
• Evolutionary Biology
• Conservation Genetics

Background:

• The Devil's Hole pupfish (Cyprinodon diabolis) is a critically endangered species, often cited as an exception to theories on population persistence.
• It is widely believed to have survived in isolation for 10,000–20,000 years, but this has not been scientifically validated.

Purpose of the Study:

• To evaluate the long-term persistence hypothesis for the Devil's Hole pupfish population.
• To estimate the species' time to extinction and coalescence using empirical data.

Main Methods:

• Analysis of historical population count data for Cyprinodon diabolis.
• Estimation of time to coalescence using microsatellite genetic data.

Main Results:

• The estimated mean time to extinction is 360–2900 years (median 410–1800 years).
• There is a less than 2.1% probability that the species will persist for 10,000 years.
• Median times to coalescence ranged from 217 to 2530 years, with broad credible intervals.

Conclusions:

• The Devil's Hole pupfish population likely colonized its habitat much later than previously assumed, possibly within the last few hundred to few thousand years.
• The species' persistence may be shorter than the widely accepted 10,000–20,000 year timeframe.
• Human intervention is a potential factor in the species' introduction to its current habitat.