Additional files [RJEE Vol. 10 (4). 2025 – 5]

• Fig. 1. Map-diagram of the research area
• Fig. 2. Dynamics of fertility of females of different ages
• Fig. 3. Variability of absolute fertility of females in different water bodies
• Fig. 4. Dynamics of relative fertility of females of different ages
• Fig. 5. Diameter of fish eggs depending on geographical distribution
• Fig. 6. Ovaries of sunfish of the IV stage of maturity: 1 – the senior generation of oocytes filled with yolk (1st portion); 2 – the second generation, the beginning of vacuolization; 3 – third generation; 4 – empty follicles