Patagonian toothfish (Dissostichus eleginoides) or "Chilean sea bass" support a valuable and
controversial fishery, yet their life history is not well understood and longevity estimates
range from approximately 20 to more than 50 years. In this study, lead-radium dating
provided valid ages for juvenile to older adult groups, which were consistent with the
counting of otolith growth zones in transverse otolith sections, and longevity estimates
exceeding 30 years. Lead-radium dating revealed minor biases between the radiometric age
and interpretation of growth zone counting for regional fishing areas monitored by two
facilities, Center for Quantitative Fisheries Ecology (CQFE) and the Central Ageing Facility
(CAF), using different age estimation techniques. For CQFE, under-ageing of ca. 3.3 years
was observed across estimated ages younger than 20 years. For the CAF, ages were
overestimated for young fish and underestimated for the oldest fish. Lead-radium dating
detected underlying problems in coordinating age estimation between geographically
separated fish stocks, and provided a framework to objectively assess otolith interpretation
and growth modeling between laboratories based on age-validated data.
Lead-radium dating provides a framework for coordinating age estimation of Patagonian toothfish (Dissostichus eleginoides) between fishing areas
Document Number:
WG-FSA-11/P01
Agenda Item(s)
Publication:
(Marine and Freshwater Research, 62(2011): 781–789)
Abstract