Age and growth of two populations of Pugilina cochlidium (Gastropoda: Melongenidae), from Thondi coast-Palk Bay in Tamil Nadu-South East coast of India

Abstract Age and growth of two populations of Pugilina cochlidium were studied. to address the lack of basic information on the growth rates and the size at sexual maturity of organism in a commercially harvested area, which will be important in considering the size limits to conserve this resources in future. In the present study the results showed more or less similar growth patterns in the males and females of two populations of Pugilina cochlidium. The age and growth estimation of these two populations of Pugilina cochlidium were completed using several methods and the outcome of one method will act as a check and control over the other using the FISAT 1 software. The values of asymptotic length (Lα) values obtained in the present study using various methods did not vary greatly. Lα values obtained for the first population of Pugilina cochlidium was 95.55 mm for males and 106.05 mm for females and the growth rate (K) for males (0.588 yr-1) and females (0.620 yr-1) was given by k-scan routine in ELEFAN. Similarly, the values of asymptotic length (Lα), obtained for second population of Pugilina cochlidium, was 96.15 mm for males and 106.05 mm for females and the growth rate (K) for males (0.540 yr-1) and females (0.950 yr-1) was given by k-scan routine in ELEFAN.摘要：本研究针对商业捕捞区域内拳螺（Pugilina cochlidium）的生长速率、性成熟体长等基础信息匮乏的问题，对其两个种群的年龄与生长特性展开了探究，以期为未来制定该渔业资源的保护体长限制提供科学参考。本研究结果显示，两个拳螺种群的雌雄个体均呈现出较为相近的生长模式。研究采用多种方法完成了两个种群的年龄与生长估算，并借助FISAT 1软件，以其中一种方法的结果作为对照，对另一方法的结果进行验证。本研究通过多种方法得到的渐近体长（asymptotic length, Lα）数值差异较小。首个拳螺种群的渐近体长：雄性为95.55 mm，雌性为106.05 mm；其生长速率（K）分别为雄性0.588 yr⁻¹、雌性0.620 yr⁻¹，该结果由ELEFAN模块中的k-scan程序得出。与之类似，第二个拳螺种群的渐近体长：雄性为96.15 mm，雌性为106.05 mm；其生长速率分别为雄性0.540 yr⁻¹、雌性0.950 yr⁻¹，该结果同样由ELEFAN模块中的k-scan程序得出。