Results of the von Bertalanffy model fitting exercise.

Columns 2–4 depict the orthogonal combination of parameters; one region indicates the parameter was not allowed to be different between the high and low productivity subregions, two regions indicates the parameter was allowed to vary between subregions. Ln likelihood is the negative ln likelihood of the model fit to the data. AIC = Akaike Information Criterion. D = the test statistic of the likelihood ratio test comparing alternative models (2–8) to the null model (model 1). Df = degrees of freedom. P-value refers to the likelihood ratio tests comparing alternative models to the null.