Radiocarbon (14C) activity in the world's oceans roughly doubled between 1950 and 1970 a s a result of the atmospheric testing of nuclear weapons.Through comparison with the I4C time series reconstructed from nearby corals, Kalish (1993) used the I4C activity of fish otolith cores a s a means of confirming the annulus-based age estimates for those fish.Here I report the first pre-and post-bomb I4C chronology based only on young fish otoliths, thus avoiding all assumptions concerning the age and dale of uptake into the otollth, and any requirement for reference coral chronologies.On the basis of acc,clcrator mass spectrometry (AMS) assays, the I4C activity of 103 young haddock bfelanogrammus aeglcfinus otoliths collected off the eastern coast of Canada increased sharply betwccn 1958 and 1965 and remained elevated theredfter, in phase with published '"C chronologies for bivalves and corals in the North Atlantic.Assays of the '"C content of the extracted otolith core of old haddock served as a dated marker of the year of hatch, thus providing an absolute dge determination for individual fish which was accurate to w ~t h l n 1 to 2 yr.Internationally accepted criteria for annulus interpretation in haddock otoliths appear to be accurdte to an a g e of at least 10 yr, a n d to within 2 to 3 yr for haddock up to an a g e of 22 yr.
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Steven E. Campana (1997) studied this question.