Abstract

Black sea bass, Cenrropristis striata, were collected during 1991 - 1995 at randomly selected reef sites throughout the South Atlantic Bight (SAB) and were aged by two readers using whole sagittae. At the conclusion of the ageing study, perusal of the data suggested a clumped distribution of specimens marked as unreadable (i.e., aberrant). Sample sites located within +- 0° 0.4’ lat./long. or less of each other, and which were sampled in at least three of the five years, were labelled “areas of aberrancy”. Three such areas were identified, and all were off South Carolina in depths of 26 - 44 m. Total ocurrence of aberrant otoliths in the areas of aberrancy (38 of 135 specimens; 28. 1%) was significantly greater (X2: P < 0.001) than in the rest of the SAB (158 of 1,786; 8.8%). Although only 7.6% of black sea bass were collected in the areas of aberrancy, 19.4% of all aberrant otoliths encountered were from these areas. Further, occurrence in each of the three areas was significantly greater than in the rest of the SAB (X2: p < 0.001 for all). Lengths of fish from the three areas suggested that individuals of ages one through at least four had aberrant otoliths. The reason why aberrant otoliths occurred with unusually high frequency in small, isolated areas is not apparent. If the cause is an unusual combination of physical conditions in the three areas, further study may assist in our understanding of calcium metabolism and variation in fish growth. On the other hand, if otolith aberrancy is a heritable trait, the dispersion pattern of affected fish could be used to examine stock structure and recruitment.

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