Using Computer Tools to Automate Age and Growth Measurements from Fish Otoliths

Abstract

Otoliths are calcium carbonate structures found in the inner ear of fish. Otoliths have been found to create daily growth rings and can therefore be used to establish fish age. In this study over 500 fish otoliths were counted by microscope and then Julian age was determined by back calculation. The expectation of this study was that differences in the physical and biological conditions of two study streams would manifest in different patterns of growth and survival for stream rearing coho salmon.