Program CAPQUOTA - Two Age Model (Pollock 1981; Biometrics 37: 521-529)

Program CAPQUOTA is intended to aid in the design of capture-recapture and capture-resighting experiments. For specified capture probability, sighting probability, survival rate, population size and sampling design, the program outputs the coefficients of variation (c.v. = standard error of parameter estimate) expected for population size (adults only) and survival rate (young and adults) estimates based on the models of jolly (1965; Biometrika 52:225-247) and pollock (1981; Biometrics 37: 521-529). The biologist can then select the desired c.v. and obtain a good idea of the sampling effort (reflected in the magnitudes of capture probability and/or sighting probability) needed to produce this level of precision.

The following input data are needed:

Number of sampling periods
Number of periods between capture periods
Adult survival rate
Adult resighting probability
Proportion of young/adult population size
Young survival rate
Proportion of young/adult capture probability
Population sizes (start,fin,inc) , ,
Capture probabilities (start,fin,inc) , ,

Arithmetic Mean Geometric Mean