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The article presents the study which shows that the estimation of the population growth rate is robust to individual detection heterogeneity (IDH). The study analyzed the wolf data in France to estimate population growth rate using capture-recapture (CR) models accounting for IDH. It is concluded that the bias in population growth rate increased with detection heterogeneity but was low whether CR model used with IDH or not.

Assessing conservation strategies requires reliable estimates of abundance. Because detecting all individuals is most often impossible in free-ranging populations, estimation procedures have to account for a <1 detection probability. Capture–recapture methods allow biologists to cope with this issue of detectability. Nevertheless, capture–recapture models for open populations are built on the assumption that all individuals share the same detection probability, although detection heterogeneity among individuals has led to underestimating abundance of closed populations. We developed multievent capture–recapture models for an open population and proposed an associated estimator of population size that both account for individual detection heterogeneity (IDH). We considered a two-class mixture model with weakly and highly detectable individuals to account for IDH. In a noninvasive capture–recapture study of wolves we based on genotypes identified in feces and hairs, we found a large underestimation of population size (27% on average) occurred when IDH was ignored. [ABSTRACT FROM AUTHOR]