A preliminary assessment of age and growth of eel cod (Muraenolepis sp.) and violet cod (Antimora rostrata) in the Ross Sea, Antarctica

Samples of an eel cod (Muraenolepis sp.) and violet cod (Antimora rostrata) were obtained from the bycatch of the longline fishery for toothfish (Dissostichus mawsoni and D. eleginoides) in the Ross Sea, Antarctica. Counts of zones visible in sectioned otoliths were used to estimate growth parameters for these species. The estimates must be considered preliminary because they are unvalidated, the otoliths are quite difficult to interpret, and the sampled fish do not represent the full length or sex distributions of the populations (i.e., small fish and males were absent). The Muraenolepis samples were not identified to species. However, they were obtained from a relatively confined areal and depth range, so probably comprise a single species. They are relatively short-lived, with a maximum estimated age of 9.5 years. Von Bertalanffy parameters derived from female and unsexed fish only are: L., 42.8 cm TL; K, 0.408 y-1; t0, -0.1 years. Violet cod are relatively long-lived, with a maximum estimated age of 41.5 years. Von Bertalanffy parameters derived from female and unsexed fish only are: L., 78.4 cm TL; K, 0.053 y-1; t0, 0.1 years.