A genetic analogue of 'mark-recapture' methods for estimating population size: an approach based on molecular parentage assessments

Molecular polymorphisms have been used in a variety of ways to estimate bot h effective and local census population sizes in nature. A related approach for estimating the current size of a breeding population, explored here fo r the first time, is the use of genetic 'marks' reconstructed for otherwise unknown parents in paternity or maternity analyses of progeny arrays. This method provides interesting similarities and contrasts to traditional mark -recapture methods based on physical tags. To illustrate, this genetic meth od is applied to a population of painted turtles on the Mississippi River t o estimate the number of successfully breeding males. Non-genetic mark-reca pture approaches were also applied to animals trapped at this location. Res ults demonstrate that such genetic data on parentage can be helpful not onl y in estimating contemporary population sizes, but also in providing additi onal information, not present in customary mark-recapture data, about possi ble extended movements of breeding individuals and the size of the pool of mates which they encounter.