Population structure growth pattern and exploitation level of Otholithes ruber in Balochistan, Pakistan

다국어 초록 (Multilingual Abstract)

Relative growth pattern, mortality rate and exploitation status of Otholithes ruber was investigated in the Balochistan, Pakistan between September 2020 and February 2021. A total of 1,308 samples of O. ruber were collected and length and weight of each individual fish was measured. The monthly length frequency data were analyzed using FiSAT II computer software package. The mean total length and body weight of the O. ruber was 30.34 (4.814±) cm and 288 (157±) gm respectively. Length-weight relationship was W = 0.0036L^3.2815 (r² = 0.9445) showing a positive allometric growth. The estimated von Bertalanffy growth parameters (L∞ and K) for O.ruber were as L∞ = 54.28 (cm) and K = 0.51 yr^-1 , t₀ = -0.271yr^-1 the longevity (t_max) was 5.88 years . The total mortality rate (Z) was calculated 2.58 year^-1. Natural mortality (M) was estimated at 1.01yr ^-1, The exploitation rate was found to be 0.61 yr. ^-1 that is 22% higher than the optimum level of exploitation (E = 0.50). It could be concluded that fishing pressure was 22% higher, which means fishermen did not stop their fishing activities during covid19 period in the investigated region.