|
Changes in demographic parameters based on the length of Black pomfret (Parastromateus niger, Bloch, 1795) during the past decades in the northern waters of the Oman Sea (Sistan and Baluchistan Province)
|
Mastooreh Doustdar *   , Seyed Ahmadreza Hashemi |
|
|
|
Abstract: (430 Views) |
| The purpose of this research is to investigate the fishing situation, fishing indicators and population characteristics of this species fish in the study area based on length during the past decades. Investigating of stock status can be an important tool for fisheries managers and planners for better and sustainable management of aquatic resources and should be given more attention. During the years of this study) 1992 and 2022(, 2469 fish were measured and the average length (±95% confidence limits) of black pomfret fish in 1992 and 2022 was 39±5 (34-44) cm and 36±8 (28-44) cm, respectively. The average weight (±95% confidence limits) of this species was 1560 ±570 (990-2130) grams in 1992 and 1310±750 (560-2060) grams in 2022. The relationship between fork length and body weight for the year 1992, W=0.13*L^2.56 (R2=0.86, N=731) and the year 2022, W=0.6*L^2.74 (R2=0.95, N=691) was obtained and the amount b of the relationship between length and weight was an indication of allometric growth. Vonbertalanffy equation for this species in the northern waters of the Oman Sea (Sistan and Baluchistan Province) was calculated in 1992 and 2022 respectively as: Lt =74 (1-exp (-0.41 (t +0.31)) and Lt =66 (1-exp (-0.59 (t +0.22))). The maximum sustainable yield (MSY) and the ratio of current biomass to initial biomass (B/BV or B/B0) in 1992 and 2022 were estimated as 313 tons, 0.34 and 3361 tons, 0.43, respectively. The ratio of spawning potential based on length in 2022 and 1992 were 0.28 (0.24-0.31) and 0.17 (0.13-0.21), respectively. Decrease of the average length, average weight, exploitation rate, the fishing mortality to the fishing mortality of the maximum sustainable yield (F/FMSY >1) and the ratio of current biomass to initial biomass (B/BV or B/B0), can be a reason for overfishing |
|
| Keywords: Parastromateus niger, Spawning potential ratio, Vonbertalanffy equation. |
|
|
Full-Text [PDF 986 kb]
(139 Downloads)
|
Type of Study: Research |
Subject:
Special
Received: 2023/01/15 | Accepted: 2023/08/15 | Published: 2024/10/21
|
|
|
|
|
|
|
| Send email to the article author |
|
|
|
| Add your comments about this article |
|
|
|
