Demersal resources change based on swept area method in the northern waters of Oman Sea (Sistan and Baluchestan Province)

For more than two decades, assessment and monitoring of Oman Sea demersal resources has been carried out using swept area method. The study area starts from western water of Iran to border of Iran and Pakistan in the east of Oman Sea and total study area were divided into 5 sub-areas A to E in different depth layers of 10-20, 20-30, 30-50 and 50 -100 meters. In general, the average amount of biomass has a downward trend in different depths of 2003 to 2021 years(P<0.05). Some species fish such as Otolitus ruber, Pomadasys kaakan, Ray and sharks in fishing composition have decreased sharply and some species fish such as Saurida tumbil, Sphyraenidae, Carangidae and Mullidae in fishing composition have increased. Considering the mentioned conditions, it seems that the amount of demersal resources caught is not in a good condition and measures should be taken to reduce the catch of these fish.