| Abstrak/Abstract |
Small pelagic fish called shortfin scad (Decapterus macrosoma Bleeker, 1851) are primarily
caught in the waters southern of the Special Region of Yogyakarta and are highly valuable economically.
In this study, the morphological characteristics of the otoliths and the relationship between
morphometrics of the otoliths and fish length and weight in the shortfin scad were examined. The
shortfin scad samples were taken randomly as much as 35 kg with a total of 119 individuals caught by
fishermen operating purse seines in October 2022. A total of 112 pairs of intact otoliths were collected,
consisting of 59 pairs of males and 53 pairs of female otoliths. Each otolith's morphometrics were
measured, including length, width, area, perimeter, and mass. The shape of the otolith was determined
by calculating the six index indicators which include roundness (RO), form factor (FF), rectangularity
(Rt), circularity (C), aspect ratio (AR), and ellipticity (E). T-tests were performed on the left and right
otoliths, also between the male and female otoliths. The otolith sagitta of shortfin scad was typically
oval-shaped, elongated, and had an irregular surface. The left and right otoliths were similar in size and
shape and frequently symmetrical. The linear regression equation y = ax + b can be used to describe the
relationship between otoliths length and total length. There is an isometric relationship between the
otolith morphometrics of sex and position. The lengthening of the otoliths may indicate a significant rise
in fish size. |
