According to the public relations office of Iranian Fisheries Science Research Institute, Dr. Mahmoud Bahmani, noting that 98% of the northern fishing basket is whitefish and mullet, said: "Unfortunately, during the last three decades, the stocks of these fishes have decreased and this downward trend will continue also in the next year. According to Dr. Bahmani, a number of factors have caused such problems as the impossibility of fish migration due to human interference in rivers tarcks, illegal and uncontrolled fishing, water pollution and conditions that disrupt the order of the ecosystem are among the most important of them. Dr. Bahmani continued: "During the last two years, Iranian Fisheries Science Research Institute, in a promotional project in cooperation with Iran Fisheries Organization, has started studies in which important measures regarding natural and semi-natural reproduction of whitefish are taken with the participation of local communities." To take. He also said: "There are 177 species in Caspian Sea and its catchments, of which 80 species are exclusive, 54 species are native and 43 species are non-native. The presence of non-native species, in most cases, is disturbing the balance of the ecosystem of the area and its natural tranquility.” Declaring that in sustainable development, various elements should be considered, including economic, social and environmental elements, Dr. Bahmani added: "Every person should be responsible for the environment, because it is the guarantor of the survival of the humankind." Researchers at Iranian Fisheries Research Institute, with a 102-year history, have put an in-depth look consistent with sustainable development at the forefront of their work, and to succeed in this way, more attention needs to be paid to research issues and scientific studies.