Estimating the spawning and growth of striped snakehead Channa striata Bloch, 1793 in Lake Rawa Pening Indonesia

The striped snakehead (Channa striata Bloch, 1793) is a commercially important fish in Lake
Rawa Pening, central Java, Indonesia. This study aims were to investigate their age, growth, and
recruitment pattern, through a sampling that was performed monthly, from November 2017 to
August 2018. The individual fish was measured for length and weight, and sex was determined. The
otoliths were collected, cleaned, and placed on molds to pour epoxy resin. The otoliths were cut to
obtain slices and observed under a microscope at 100 × magnification. Subsequently, the age was
determined by counting the number of daily rings. It was established that the snakehead spawned
every month, with a comparably higher frequency in the new moon than in other phases, and mostly
were 3–10 months old, characterized by bigger and older sizes during the rainy season. Furthermore,
the average growth rate was observed to be faster during the rainy season in contrast with the
dry season. Hence, the parameters of von Bertalanffy growth functions were estimated by backcalculated
length, and the pattern in female was Lt = 56.09 (1 − e−
0.81 (t + 0.07)), while male Lt = 59.36 (1
− e−
0.71 (t + 0.09)), and total Lt = 60.32 (1 − e−
0.71 (t + 0.14)), respectively.