Length-weight relationships and growth patterns of Lutjanus malabaricus and Lutjanus johnii from the northwest coast of India Veraval, Gujarat

Abstract

The present study investigates the length-weight relationship (LWR) of two commercially important lutjanid species, Lutjanus malabaricus and Lutjanus johnii, landed at the Veraval fishing harbour along the Saurashtra coast of Gujarat, India. Sampling was conducted over a six-month period from December 2024 to May 2025, during which a total of 602 specimens were analyzed (302 L. malabaricus and 300 L. johnii). Total length and body weight were measured, and LWR parameters were estimated using the allometric equation W = aLᵇ. For L. malabaricus, the pooled LWR was W = 0.0043L²·⁹⁸ (r² = 0.95), indicating near-isometric growth, with males showing positive allometric growth and females exhibiting slightly negative allometry. In L. johnii, the pooled relationship was W = 0.0052L³·⁰³ (r² = 0.989), suggesting near-isometric to weak positive allometric growth, with distinct sex-specific growth patterns. High coefficients of determination in both species confirm a strong correlation between length and weight. Comparisons with earlier studies revealed regional variability in growth coefficients, likely influenced by environmental conditions, population structure, and sampling differences. The findings provide valuable baseline information for stock assessment, fisheries management, and sustainable exploitation of lutjanid resources along the Gujarat coast.