Seven Pelagic-neritic Fish Species from the Leiognathidae Family at the Sundarban Delta Estuarine Mouth of the Bay of Bengal in West Bengal, India: Condition Factor, Length-weight Correlations and Morphometric Features

Aims: First-hand data regarding the length-weight relationship (LWR) and condition factor of seven pony and slipmouth fishes (family: Leiognathidae) from the Sundarbans delta estuarine mouth of the Bay of Bengal in West Bengal, India, with special focus on morphometric relationship, is presented in this study. Study Design: Established the Length-Weight relationship through Log W = Log a + b Log L and condition factor (K) through K=100*W/L3. Morphometric characters percentage with total length (% of TL) of seven commercially important pelagic pony and slipmouth fishes from the Estuarine mouth of the Bay of Bengal, West Bengal. Place and Duration of Study: Between January 2024 and July 2025, fish samples were collected at 10- to 20-day intervals from various brackish water islands and fish landing centres in South 24 Parganas and the Sundarbans estuarine islands, West Bengal. Methodology: The relationship between a fish's body length and its total weight is often described using a length-weight relationship (LWR) equation, typically expressed as W = aLb, where W is weight, L is length, and 'a' and 'b' are constants specific to a species. This relationship helps in understanding fish growth, condition, and biomass estimation. The specimens were collected from several fish landing centers using scoop nets (1× 1 mm to 6 × 6 mm), gillnets (4.0–40 mm), and cast-nets (5 × 5 mm to 10 × 10 mm up to 4.5 m2 areas). Results: Based on our research, the family Leiognathidae exhibited negative allometric development (b < 3), meaning that their length increases more rapidly than their weight. The correlation coefficient (R2) value is between 0.8523 to 0.9582, and the condition factor (K) has respective values between 0.979 to 1.78. Conclusion: From this Fishery research, stock assessment, conservation, and the assessment of the fish condition of the Sundarbans estuarine islands, West Bengal, India.