Design considerations for estimating survival rates with standing age structures

Survival rate estimates are critical to understanding the dynamics and status of a population, and
they are often inferred from samples of the population’s age structure. A recently developed method uses time
series of standing age-structure data with information about population growth rate or fecundity to provide
explicit maximum likelihood estimators of age-specific survival rates, without assuming population stability or
stationarity. We explored properties of these estimators and determined sample size requirements for the
estimators to achieve desired levels of precision, limit bias, and limit the probability a rate will be inestimable or
its estimate inadmissible (>1).We show that estimating combined rates for adjacent age classes is an effective
method of overcoming sensitivity to sampling noise in situations where collecting a larger sample of data is not
feasible.