Age and Growth of Amur Barbell

Abstract

This study evaluates the age and growth of Amur barbell (Hemibarbus Labeo) in Geo-san Lake, South Korea via vertebra reading methods. The samples were collected between March and October 2011, 201 specimens ranging in total length (TL) from 125.5 to 421.0 mm, total weight (TW) from 14.6 to 599.2 gm and the maximum estimated age was 10 years. The samples were collected by gillnets and trap nets. Vertebrae of 65 (56.5%) female and 50 (43.5%) male were analyzed. Age determinations were made by vertebrae microscopic observations. The index of average percentage error (IAPE) estimated from two reading (ranged from 0.02 to 0.39 and mean 0.18. And coefficient of variation (CV) ranged from 0.04 to 0.78 and mean 0.23. The monthly marginal increment (MIR) ratio revealed a tendency toward band pair deposition between autumn and winter which indicate that ring marks form once a year, Length frequency distributions showed differences in the range of sizes between the sexes, all specimens larger than 387.3 mm in total length were female. The obtained results were compared with those of the previous studies, The relationship between total weight (W) and total length were expresses as W= 1E-05L2.974 (n=65, r2=0.9885, p < 0.05) for female and W = 9E-06L2.9991 (n=50, r2= 0.9834, p < 0.05) for male, Based on the MIR analysis, growth band pairs (including translucent and opaque bands) in vertebrae formed once a year and were counted up to 10 and 8 for females and males, respectively. Growth parameters were derived using the Von Bertalanffy Growth Function (VBGF), Parameters derived from observed lengths, K = 0.08, L∞ = 692, r2=0.92 cm and t0 = -0.127 year for female and K = 0.1, L∞ = 641, r2=0.93 cm and t0 = -0.120year for male. Parameters derived from back-calculation length, K = 0.054, L∞ = 744.39, r2=0.99 cm and t0 = -0.176 year for female and K = 0.060, L∞ = 708.11, r2=0.98 cm and t0 = -0.164 year for male, were considered to best describe growth