Summary
The smallest population size with a high chance of long-term persistence.
In depth
Often cited rules of thumb: 50 for short-term inbreeding avoidance and 500 for long-term evolutionary potential (50/500 rule), later revised upward to 100/1000. Depends on species.
MVP depends on goals and risks. Genetic needs (Ne) are lower than census size. Revised estimates are thousands for long-term persistence.
Remember: effective population size is usually smaller than census size.
The minimum viable population (MVP) is the smallest isolated population with an acceptable probability (often 90 to 99 percent) of surviving for a set period (often 100 to 1,000 years), allowing for chance events and genetic problems. Mark Shaffer introduced the concept in 1981.
Estimates vary hugely by species and depend on life history and environment. A rule of thumb is the 50/500 rule: an effective population (Ne) of at least 50 avoids short-term inbreeding depression, and 500 maintains long-term evolutionary potential, though more recent work suggests 100 and 1,000 or more. Effective size is usually much smaller than the census count because of unequal sex ratios and variance in reproductive success.
Example: northern white rhinos, with only two females left, are functionally extinct.
Key idea: very small populations are at high risk.
Frequently asked questions
What is Minimum Viable Population?
The smallest population size with a high chance of long-term persistence.
Which area of biology covers Minimum Viable Population, and how advanced is it?
Minimum Viable Population is one of the 52 topics in Taxonomy & Biodiversity. It is rated Advanced, so it suits learners who want specialist depth. Related topics in this area include Population Viability Analysis, Extinction Rate Estimation, Genetic Rescue.
Can you give an example of Minimum Viable Population?
Grizzly bears in Yellowstone have been modelled with this idea.
What should I learn before Minimum Viable Population?
Work through the Beginner topics in Taxonomy & Biodiversity first, such as Taxonomy, Binomial Nomenclature, Taxonomic Hierarchy, then return to Minimum Viable Population. Advanced topics assume the Intermediate vocabulary.
What topics are related to Minimum Viable Population?
The closest topics to Minimum Viable Population are Population Viability Analysis, Extinction Rate Estimation, Genetic Rescue, Genetic Diversity. Comparing them side by side is a good way to see how the ideas connect.
How can I check that I understand Minimum Viable Population?
Read the summary and the in-depth section, then use the quick check on the interactive lesson for Minimum Viable Population. To practise the whole of Taxonomy & Biodiversity, use the Taxonomy & Biodiversity quiz.
How is Minimum Viable Population different from Population Viability Analysis?
Minimum Viable Population: The smallest population size with a high chance of long-term persistence. Population Viability Analysis: Models estimate the probability a population persists given demographic and environmental risks. Read both side by side and note what each one explains.
How should I study Minimum Viable Population step by step?
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with Population Viability Analysis and explain the difference aloud. Finally, take the Taxonomy & Biodiversity quiz and come back to this page for any question you miss.