The relation between daily rings, body growth and environmental factors in plaice, Pleuronectes platessa L., juvenile otoliths

The deposition rate of sagittal otolith rings in post‐metamorphosed plaice, Pleuronectes platessa, was considered in relation to body growth under three feeding levels and two photoperiod regimes. Feeding levels and photoperiods significantly influenced the number of rings; more rings were deposited at higher levels of feeding and in longer photoperiod regimes. There was also a linear relationship between fish growth and the number of rings. The results suggest that sagittal rings could be used for aging wild juvenile plaice during the period of the growing season when growth rate is greater than 0.1 mm day1.