NUMBAT OER - Open Educational Resources

1. Introduction

Mark-release-recapture is a technique for estimating the size of a population of mobile animals where it is likely to be impossible to count all individuals from a given piece of habitat. A number of animals are captured within a habitat, and are marked in a way that makes them easily recognized when they are encountered again. The marked animals are released into the same habitat, and it is assumed that they will mix back into the rest of the local population. The same habitat is then resampled, and the number of marked and unmarked animals caught in the second sampling is noted. The proportion of animals marked in the first sampling that is recaptured in the second sampling can then be used to calculate an estimate of the overall population size, if certain assumptions are satisfied.