Population Structure and Fishery Perspectives of Big-Scales and Smelt Atherina boyeri in Ukrainian Waters of the Northwestern Part of the Black Sea and the Tiligul Estuary

The paper deals with the size/age and sex composition and natural mortality of the big-scale sand smelt <i>Atherina boyeri </i>(Risso, 1810) based on material collected over the years 2017-2021 in the northwestern section of the Black Sea (NWBS) and in 2024 in the Tiligul estuary. It was found that yearlings and two-year-old specimens form the stock bulk in NWBS. The maximal age in the Black Sea was 4+ and in the Tiligul estuary 3+. The specimens from the Black Sea were characterized by higher growth rates than those from the Tiligul estuary. Females prevailed in both water bodies, their portion increases from the age of two years. The decline of the big-scale sand smelt yield over the recent decades is conditioned mainly the regulatory limitations of fishing. The measures are proposed to improve the stock state and the yield increase, in particular by the fishery regulation optimization and intensification of water exchange between the sea and estuaries.