Age reading by use of otoliths is one of the basic but
also most essential elements in practical fish population
dynamics. Unfortunately, many factors can influence the
readings of a single reader. Erronous readings, however,
have a consequential effect on the evaluation and
prediction of the development of the fish stock under
consideration. In order to master this problem and to
reduce out the effect of those factors, it seems neccessary
to standardize the whole process of age reading
between collaborating readers. From a statistical point
of view calibration techniques can be used to identify
those factors and to correct the readings with respect to
them. The current article presents an overview over the
basic idea behind this, over how to balance out the existing
deviations and how to correct the age readings
