Relationship between Repaired shell dam age and fishing disturbance in the patagonian scallop Zygochlamys patagonica

Shell damage and abnormal calcifications are a common phenomenon in bivalve molluscs and can result from a series of interactions or disturbances that often lead to different, distinctive marks. For example, burrowing activities cause damage and chipping of the shell edge. Attack by crabs increases the number of scars in the shell, birds break the posterior margins of the valve or fragment the shells leaving recognizable marks. Moreover, disturbances such as commercial dredging, increase the incidence of scars in the shells of Artica islandica, Glycymeris glycymeris Ensis arcuatus and E. siliqua. If properly evaluated, all these marks can be useful to understand the relative importance of different disturbance sources in different locations.