Age and growth of Capoeta pestai (Actinopterygii: Cypriniformes: Cyprinidae) in a small river entering lake Eğirdir, Turkey

Abstract

Background. Capoeta pestai (Pietschmann, 1933) is commercially important fish species in Turkey. The knowledge of the biology of this species is very scarce. This species has a ‘critically endangered’ status on the IUCN Red List. The objective of this study was to determine the age and growth rates of C. pestai, and to evaluate whether otolith morphometrics could be used as an age predictor. Material and methods. Fish were collected from a small river entering Lake Eğirdir between January and December 2012. Fish samples were obtained from shallow parts of the river (30-40 cm depth) seasonally in a single station by using an electrofishing devise. Results. Annual growth increments were counted on the otoliths of 154 specimens, ranging from 6.2 to 26.8 cm total lengths. Estimated ages ranged from 0+ to 7+ years old. The von Bertalanffy growth curve was fitted to the age/total length data as follows: L∞= 47.83 cm (TL), K = 0.081, t0= -1.840, for females; L∞= 41.25 cm (TL), K = 0.086, t0= -1.99 for males; L∞= 52.45 cm (TL), K = 0.067, t0= -1.84 for all specimens. No significant differences in morphometric measures (length, width, and mass) were found between left and right otoliths (paired t-test, P > 0.05). Otolith length and width showed significant linear relations with the total length while otolith mass represented by power model. Conclusion. This study provides the first information on age, growth and otolith morphometric parameters of C. pestai. In addition, otolith morphometric measurements could possibly be used in future as an age predictor for C. pestai.