Mark–recapture population estimation
Repeated samples can estimate a population under explicit sampling assumptions.
Key knowledge
A simple two-sample mark–recapture estimator uses the fraction of marked individuals in a later sample to estimate total population size. Its interpretation depends on mixing, capture probabilities and persistence of marks, rather than only arithmetic on capture counts.
Values and equations
N̂ ≈ MC/R
- N̂
- simple estimated population size individuals
- M
- individuals marked and released after the first sample individuals
- C
- total individuals in the second sample individuals
- R
- marked individuals recaptured in the second sample; must be nonzero individuals
Conditions and scope
- Assume a closed population between samples, retained recognizable marks, adequate mixing and comparable capture probabilities.
- Capture or marking must not change survival or recapture probability; few recaptures produce high uncertainty and bias.
Sources · 1
References
Sources retain their recorded scope. A source link alone does not establish verification of every statement.
Evidence and review
Source capture-ratio example and behavioural/marking limitations.
2026-10-10 · Checked estimate versus census and required sampling assumptions; no new animal study.
Entry details
Permanent link to this entry ↗- Record identity
- bio-mark-recapture
- Revision
- university-reference.1
- Structured reference record
- University reference