Inter-Otolith Differences in Strontium Markings: A Case Study on the Juvenile Crucian Carp Carassius carassius (Linnaeus, 1758)

The release of hatchery-reared fish fry for restocking is important the enrichment fishery resources; however, effective evaluation success rate marking such challenging. We exposed juvenile crucian carp (Carassius carassius) to a single concentration SrCl2·6H2O 5 d and evaluated efficiency Sr otoliths (sagittae, asterisci, lapilli) using an electron probe micro-analyzer. signatures formed peak in all otolith types, with 100%. ratio Ca lapilli sagittae was higher than that asterisci. It took 2 from beginning immersion deposition on sagittae, time delay asterisci 1 d. For it 16 terminate fully recover pre-marking level, whereas 12 application dose had no effect survival or growth carp. This study demonstrated are most suitable type observations provides theoretical basis technical support approach.