Age-distribution models for fish in catches

Resumo

Models that describe the age distributions of fish in catches are discussed. On the logarithmic scale of the Y-axis, the right (descending) part of these curves can be straight or can have an upward or downward concavity, as well as a sharp bend in the middle. These properties of the curves can be explained by variations in the intensity of mortality between different age groups or by demographic variations in the super-population systems. Illustrations of a catch using age curves are provided.