The early life history of turbot (Psetta maxima L.) on nursery grounds along the west coast of Ireland: 2007-2009, as described by otolith microstructure

The early life history of turbot (Psetta maxima Linnaeus) was investigated over a three year period (2007-2009). 0-group turbot were collected in September of each year, from three nursery areas along the Irish west coast. The timing of hatching and settlement and the duration of the larval stage were estimated using otolith microstructure analysis. Otolith increment widths were used to derive an index of relative growth rates before and after settlement. Turbot were estimated to have hatched between May and June and settled onto nursery grounds between June and July over the 3 years of the study. No inter-annual differences in the timing of hatching or settlement were observed. Spatial variability was detected, with turbot collected from one location hatching and settling significantly earlier compared to other locations. Turbot from the same location also displayed higher post-settlement otolith growth rates suggesting that this may be a nursery of high habitat quality. Turbot captured in 2009 exhibited significantly shorter larval durations and higher larval otolith growth rates compared to turbot collected in other years. Post-settlement growth rates displayed the opposite trend, with turbot showing lower post-settlement growth in 2009. The results provide valuable baseline data on critical events in the early life history of a data-poor species.