Back-Calculated Fish Lengths and Hg and Zn Levels from Recent and 100-Yr-Old Cleithrum Bones from Atlantic Cod (Gadus morhua)

Abstract

Dimensions of cleithrum bones from recently caught Atlantic cod (Gadus morhua) were measured and plotted against observed fish lengths to back-calculate cod lengths from cleithra from a ship wrecked in 1865. Mercury levels in the historical bones were approximately the same as those in recent material and showed no increase with fish length, but zinc levels appearto have increased since 1865 and increased with fish length.