Abstract: By using otolith-age identification technique, an every two months investigation was made on the day-age, total length, and body mass of Tanichthys albonubes in the natural waters near Luzitian village, Conghua City of Guangdong from June 2005 to April 2006. The results indicated that the T. albonubes collected in June 2005, August and October 2005, December 2005 and February 2006, and April 2006 had a day-age of 40-70, 10-130, mostly beyond 50, and mostly under 50 days, respectively. As compared with that of artificial T. albonubes population, the otolith increment of wild population was higher in definition and contrast, but not regular in width. The long diameter of wild T. albonubes otolith was linearly correlated with body length, and power-functionally correlated with body mass. The early growth of wild T. albonubes fitted exponential functions L=1.4685D^0.5824 (r=0.9081,P<0.001,n=266) and M=0.0048D^2.0122 (r=0.8844,P<0.001,n=266), where L, M and D represented body length, body mass and day-age, respectively. The age structure of wild T. albonubes was most complex in August and October, and accordingly, the breeding season of this fish was estimated from March to December.

Key words: Soil redistribution, Cesium-137 (¹³⁷Cs), Calibration models, Black soils, Northeast China