Radiometric analysis of blue grenadier, Macrunonus novaezelandiae, otolith cores

Blue grenadier, Macruronus novaezelandiae, is a major commercial fish species in the upper continental slope waters of southeastern Australia and New Zealand. An accurate knowledge ofage and growth rate of this species is required for management ofthe fishery. Several ageing studies have provided estimates of age for blue grenadier (hoki) from New Zealand waters (reviewed by Paul, 1992), with the maximum age ranging from 12 to 15 years.

In the present study measurements of ²¹⁰Pb/²²⁶Ra disequilibria have been conducted on cores of adult female blue grenadier otoliths in an attempt to provide independent age data for this species.