Length-weight Relationships and Relative Condition Factor of Indian Bartail Flathead (Platycephalus indicus) Along the Mangaluru Coast

Abstract

Indian bartail flathead (Platycephalus indicus) is a commercially harvested marine fish along the Mangaluru coast, for which local information on growth pattern and condition remains limited. This study assessed the length-weight relationship and relative condition factor of the species using 240 specimens comprising 86 males and 154 females. Samples were obtained from commercial catches at fish landing sites, and total length and body weight were recorded for length-weight analysis. The allometric relationship between length and weight was estimated, while the relative condition factor (Kn) was used to describe fish condition. The study reported negative allometric growth for both males and females, indicating that body weight increased at a lower proportional rate than length. Monthly relative condition factor values remained above one for both sexes and showed only limited variation during the observation period. Male Kn values ranged from 1.002237 to 1.055086, while female values ranged from 1.004919 to 1.054667. These observations indicate comparatively stable condition across the sampled months under the interpretation applied in the study. The results provide baseline biological information on the growth pattern and relative condition of P. indicus along the Mangaluru coast. Broader spatial and temporal sampling, together with assessment of environmental and reproductive variables, would strengthen future interpretation of population condition and support fisheries assessment and management.