|
Analysis of Overfishing Trends and Sustainability Assessment of demersal species in the Persian Gulf and Sea of Oman Using the CMSY Model
|
Seyedhmdreza Hashemi    , Mastooreh Doustdar , Paria Akbary |
| Offshore Fisheries Research Center, Iranian Fisheries Science Research Institute, Agricultural Research,Education and Extension Organization (AREEO), Chabahar, Iran. , seyedahmad91@gmail.com |
|
|
Abstract: (59 Views) |
Background and Objectives: Given the global importance of conserving aquatic resources as a fundamental axis for resource sustainability, fisheries management focuses on providing sufficient and safe food through responsible and permitted exploitation. This study investigates the trend of overfishing of demersal (bottom-dwelling) aquatic species in the southern waters of Iran from 1997 to 2024 using the surplus-production model (CMSY) implemented in R software, along with a Bayesian approach incorporating prior information and Monte Carlo simulations.
Methods: Landing data (catch discharged to shore) of Benthic aquatic animals (32 species or families)from four major catch landing areas in four southern provinces of Iran (Khuzestan, Bushehr, Hormozgan, Sistan and Baluchestan) were collected for the past 27 years (based on tons) from the Iranian Fisheries Organization (from 1997 to 2024). The extent of overfishing in the southern waters of the country was modeled using the Catch-MSY (CMSY) method, R software, a Bayesian status approach, and Monte Carlo simulation with 10,000 iterations of modeling based on probability distributions. The values of computational parameters and their confidence intervals were measured at various percentages. To compare the index values of different tuna and tuna-like species in two time periods, a t-test was used at a 5% significance level.
Findings: The mean total catch of demersal species (Yᵢ) in the southern waters over the study period (1997–2024), based on official statistics from the Iranian Fisheries Organization, was 164,333 tons, with a 95% confidence interval of 188,201–140,464 tons. The results showed that the catch increased significantly over the past two decades (p < 0.05).Fishing status was assessed using the ratio of available biomass to maximum sustainable biomass (B/BMSY). In 1997, the values indicated that overfishing (O) of demersal species in the southern waters was 10%, while the proportions of maximally sustainably fished (M) and underfished (U) stocks were 53% and 37%, respectively. By 2024, the proportions were 35% for overfishing (O), and 31% and 34% for maximally sustainable fishing (M) and underfishing (U), respectively. The mean catch of demersal species for the study period (1997–2024) increased significantly over the past two decades (p < 0.05) and was close to the global average overfishing rate for demersal species (35%). Additionally, the mean values of B/BMSY, F/FMSY, the exploitation (saturation) index (S), and depletion (d) for demersal species in 1997 and 2024 did not differ significantly (p > 0.05)
Conclusion: Overall, based on the indicators and conditions evaluated, the level of overexploitation of demersal species in the southern waters of Iran appears to be in the low to moderate range |
|
| Keywords: Demersal species, CMSY model (CMSY), Overfishing value, Exploitation rate |
|
|
|
Type of Study: Research/ Original/ Regular Article |
Subject:
Fisheries and Aquaculture
Received: 2026/04/18 | Revised: 2026/07/8 | Accepted: 2026/06/5
|
|
|
|
|
|
.jpg)
.jpg)
