Estimation of growth parameters and mortality rate of Upeneus sulphureus (Cuvier, 1829) in the Persian Gulf ecosystem

Abstract

Population parameters were estimated for goatfish (Upeneus sulphureus, Cuvier, 1829) as a small size and abundant species in the Persian Gulf ecosystem. A method of Tropfish R package based on length frequencies analysis was used. A total of 520 fish samples were taken monthly from landing stations in the coastal area of Iranian Waters in the Persian Gulf (Bushehr coasts) from January 2017 to December 2018. The length (FL) of the captured fishes varied from 8.5 to 17 cm with an average (±SD) of 11.20 (±2.24) cm.
The values of the von Bertalanffy growth function fit length frequency data for U. sulphureus (combined sex) were estimated, as k = 1.2 per year, L∞ =19.43 cm (LF). Total, natural and fishing mortality calculated, as Z=3.74 per year, M=2.21 per year and F=1.53 per year, respectively. The exploitation ratio (E) was estimated at 0.4.
The length-weight relationships of both sexes was estimated as, Log   = -1.707+3.00 log   (r = 0.92) which exhibited positive isometric growth. According to results, it could be concluded that goatfish (Upeneus sulphreus) is a relatively fast-growing and short-lived species. Although this species is not a direct target of fishermen, its ecological role in the Persian Gulf's food web due to their high abundance and high growth rate is undeniable.