Determining the growth and mortality parameters of longtail tuna (Thunnus tonggol Bleeker, 1851) using length frequency data in coastal waters of the northern Persian Gulf and Oman Sea, Iran

Abstract

Longtail tuna (Thunnus tonggol) is one of the most economically important tuna species in Iranian waters of Persian Gulf and Oman Sea. Some population dynamics parameters of this species were investigated in coastal waters of the northern Persian Gulf and Oman Sea from January to December 2014. The fork length (FL) of all specimens ranged from 27 to 107 cm, and total weight (TW) was between 200 and 12,000 g. Among the length frequencies examined, specimens with fork length in the range of 62-65 cm were the dominant group. The equation of length-weight relationship was estimated as TW = 0.00003 9 FL , respectively. The exploitation rate (E) was calculated as 0.63 indicating that longtail tuna was fully exploited in the study region.

REPRODUCTIVE BIOLOGY OF LONGTAIL TUNA (Thunnus tonggol) IN THE JAVA SEA

“…The length weight relationship in our study showed that the b value had no significant difference with 3, which indicates an isometric growth pattern. Several studies on length-weight relationship in this species have isometric growth pattern, such as Abdussamad et al (2012) in Indian waters, Kaymaram et al (2013) and Yasemi et al (2017) in Persian Gulf waters, and Hidayat & Noegroho (2018) in the South China Sea. However, the studies of Ahmed et al (2016) in Pakistan waters, Griffiths et al, (2017) in Australian waters, Darvishi et al (2003) and Khorshidian & Carrara (1993) in the Persian Gulf showed negative allometric growth patterns.…”

BIOLOGI REPRODUKSI IKAN TONGKOL ABU-ABU (Thunnus tonggol) DI PERAIRAN LAUT CINA SELATAN

“…Abdul Samad et al (2012), menyatakan ukuran ikan tongkol abu-abu di perairan India berkisar antara: 23-111 cm. sedangkan menurut Yasemi et al, (2017) ukuran ikan tongkol abu-abu di utara Teluk Persia dan perairan Oman 27-107 cm. Sementara Kaymaram et al, (2013) menyatakan ukuran ikan diperairan Teluk Persia dan perairan Oman berkisar 26-125 cm.…”