Research has shown an increase in the carp population in the Volga Delta, Russia

Researchers have discovered a trend towards simpler popular songs over the past few decades. Concurrently, a study has been conducted on the composition and size-weight of fish catches, along with the fullness of predator fish like catfish, pike perch, asp, and perch. The caught fish's linear-weight indicators align with average long-term values. The data will be utilized to forecast aquatic biological resource stocks, evaluate population statuses, and recommend catch limits for semi-anadromous and river fish. This initiative aims to improve fish resource management and ensure their sustainable use.