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The methodological fix, formalized by Lebreton, Burnham, Clobert, and Anderson in their 1992 Ecological Monographs synthesis, is to stop estimating population size directly from raw recapture counts and instead build an explicit statistical model of the capture history — the string of detections and non-detections for each individual across sessions — with separate parameters for survival probability ( $\phi$ ) between sessions and capture probability ( p ) within a session [ 2 ] . Their unified framework, built on the earlier Cormack-Jolly-Seber approach, treats $\phi$ and p as estimable quantities rather than assumed constants, and — critically — provides goodness-of-fit tests to check whether the assumption that all animals of a given class share the same $\phi$ and p is actually defensible for the data in hand.