Repaired shell damage in the commercial scallop Zygochlamys patagonica (King & Broderip, 1832), Argentine Sea.

SCHEJTER L.; BREMEC C.

JOURNAL OF SEA RESEARCH

Año: 2007 vol. 58 p. 156 - 162

1385-1101

We present an overview of repaired shell damage in the scallop (Zygochlamys patagonica) in the present commercial beds in the Argentine Sea. Presence of scars was registered in 11.962 scallops, ranging from 20 to 90 mm total height, from the fishing grounds in 2003 and also in 1995 (pre-fishery condition). Values of percentage of scarring (presence) were variable in all areas. Samples collected in 1995 showed the highest percentage of scars. As the highest records of scarring were registered during the pre-fishery condition, it does not seem possible to attribute these marks as absolute indicators of anthropogenic disturbance due to trawling activities of the scallopers. Moderate and severe damage was mostly recorded in individuals of commercial size (¡Ý 55 mm). This indicates not only the fragility of smaller scallops, but also the accumulation of damage in older organisms, probably more resistant to damage due to a thicker shell. The selective removal of commercial individuals could explain in part our results that indicate a higher percentage of repaired shell damage in 1995, when the average size of the population was also higher. Future investigations are needed to assess effects of scarring at different shell sizes (ages) properly related to levels of survival in Patagonian scallops thrown back to the sea during the factory process on board.