Age estimation methods in the marine gastropod Buccinanops globulosus comparing shell marks and opercula growth rings

ABSTRACT

Age determination in gastropods is an essential tool for understanding the main aspects of population dynamics that allow for the formation of fisheries policies. Small-scale fisheries of the nassariid gastropod Buccinanops globulosus from northern Patagonia are not yet regulated, although it is locally consumed while an incipient commercialization is taking place. The aim of this study was to show the suitability of opercula readings for age estimation in B. globulosus, compared with shell marks, previously validated by the analysis of the stable isotope of oxygen. The individual age estimated by the opercula rings reading method did not match the estimation made by the shell marks reading method. Stable isotope analyses confirmed that shell marks were deposited annually. Proper age estimation for B. globulosus, based on recognizable external shell marks, reached up to 9 years.

RESPONSIBLE EDITOR:

• Francesc Maynou

KEYWORDS:

• Edible gastropod
• fisheries
• individual growth
• Nassariidae
• stable oxygen isotopes

Acknowledgements

The authors are members of CONICET. All research work, including sampling and laboratory investigations, complies with current Argentine laws. Drs Miguel Pascual, Martin Garcia-Azorey and Juan Pablo Livore provided helpful suggestions that greatly improved the manuscript.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by FONCyT (Fondo para la Investigación Científica y Tecnológica), including projects PICT 1232, PICT 2929, PICT 1491, PICT 1476, and CONICET (Consejo Nacional de Investigaciones Científicas y Técnicas), including project PIP 067.