A snapshot of cannibalism in 0‐group Atlantic cod (Gadus morhua) in a marine pond

Summary Cannibalism in 0-group Atlantic cod (Codas morhua) was investigated in a semi-natural marine pond using stomach content analysis . About 6000 individuals were eradicated by rotenone treatment of the pond in November 1991 . Total lengths of cod ranged from 7 .4-28.8 cm with a median of 14 .4 cm. The proportion of cannibalistic cod in the population was estimated at 1.3%. Cannibalism accounted for a daily loss of 1 .1 % of the population . The frequency of cod with >,2 cod prey per stomach was higher in the population compared with a Poisson model. Predator-prey length ratios ranged between 1 .6 and 3 .2 when estimated from otolith-length relationships . Chesson's 1983 a-index indicated that cannibalistic cod had a positive selectivity for conspecifics < 9 .0 cm in total length .