| The bay of Somme is the first French field of cockles (Cerastoderma edule) with a production amounting to 3000 tons per year on average. In order to improve the stock management, it is necessary to increase our knowledge of this species. This study is looking at the growth of the common cockle. First, was carried out a morphometric analysis of the two left and right valves, which has revealed a perfect symmetry of the shell and has allowed us to establish strong correlations among the morphometric parameters. Then, a chemical marking study has been realized with calcein and manganese in order to obtain the exact growth. Calcein marking has showed a fluorescent stria only for an half hour immersion time at 150 mg.L-1. Likewise, the manganese marking has... |
