AN ALTERNATIVE MARK-RECAPTURE ANALOG OF SCHNUTES GROWTH-MODEL

A model is described for estimating growth using mark-recapture data, and its derivation from Schnute's size-at-age model is given. The model is mathematically equivalent to that of Baker et al. (Fisheries Research, 11 (1991) 257-281) but has a parameterization better descriptive of size-based growth, and an error structure that allows for measurement error and also relates individual variations in growth to expected growth rather than size at recapture. Both models should be thought of as analogues to (rather than equivalents of) Schnute's model because they describe a different aspect of growth (growth as a function of size, rather than of age). This distinction is of importance in understanding the meaning of parameter estimates and comparing size-based growth (estimated from the mark-recapture model) with age-based growth (estimated from the size-at-age model).