Shape Analysis of Otoliths—a Tool for Indirect Ageing of Eel, Anguilla anguilla (L.)?

• Published in: Internationale Revue der gesamten Hydrobiologie und Hydrographie
• Main Authors: Doering, Peer, Ludwig, Jürgen
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 1990
• Subjects: Anguilla anguilla
• Online Access: http://dx.doi.org/10.1002/iroh.19900750607; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Firoh.19900750607; https://onlinelibrary.wiley.com/doi/pdf/10.1002/iroh.19900750607

Abstract Eel otolith shapes can be separated into distinct groups which can be assigned to certain age groups. The shape is described exactly through Fourier series using the maximum‐projection‐area. Clusters formed by the magnitudes of Fourier descriptors agreed with age groups of three year intervals by 66% (kappa = · 522, p <.001). Artificial shapes for the resulting clusters were constructed from the mean Fourier descriptors. Further studies with eels of known age are needed to validate shape analysis of otoliths as an objective measure for indirect ageing.