2016 Volume 64 Issue 2 Pages 183-191
We investigated the breeding period, otolith annulus formation and growth of the striped snakehead Channa striata population in Nasaythong District, Central Laos. The estimated minimum sizes at maturation for females and males were ca. 19 cm SL and ca. 17 cm SL, respectively, based on the gonad somatic index. The monthly change in the gonad somatic indices of sexually mature-sized specimens indicated that the species began breeding in April when the water temperature was rising and was less active thereafter. Based on the monthly changes in the marginal width of translucent zones in the sagittal otoliths, rings in the otoliths were considered to be formed by development of opaque zones at the rate of one per year between March and July during which the water temperature was seasonally elevated. This finding indicated that the otolith rings were the annuli. Growth patterns for females, males and both sexes were estimated using the age data and regressed by von Bertalanffy growth equations. The estimated sizes were ca. 10 cm SL at 1 year-old and reached ca. 30 cm in 6 year-old fish for both sexes; the growth did not differ significantly between sexes.
