The The Morphometrics, Growth and Length-Weight Relationship of Hilsa Shad (Tenualosa Ilisha) in the Down Stream Kotri Barrage Indus River, Pakistan

Abstract

Morphological characteristics and Length-Weight relationship of Hilsa Shad (Tenualosa ilisha) from the Down Stream Kotri Barrage Indus River, Pakistan are examined. A total of 25 specimens (T. ilisha) were collected from August 2019 to September 2020 and found multiple dots in their bodies. These dots were varying to some extent; few specimens have no dots while others had 12 dots. The dots consist of black color that appeared very first time in Pakistan and has no history in the past. The merits are similar but morphometric characters, body length and weight were found to be different. The maximum and minimum weight and length were noted as 254±0.7g and 31±0.6g, 21.1±0.9cm and 15.5±0.8cm, respectively. Only three specimens were found without dots present in their body followed by four dots and nine dots, however, only two specimens categorized as two dots and twelve dots, five specimens with eight dots and seven specimens with single dot. The growth of fish was found higher in one dot specimens followed by four, eight and twelve dot specimens. Results also revealed that almost all specimens exhibited an isometric growth and the Length-weight relationship was significant with r2 ?0.910 while no statistical (P?0.05) difference was found between female (A) and male fish (B). The Hilsa (T.ilisha) is a migratory fish from sea to river for breeding and spawning purpose but, unfortunately illegal fishing, local demand, environmental change and habitat destruction cause Hilsa fish to decline continuously in the Indus river of Pakistan. Therefore, it is recommended that stock assessment with genomic studies of Hilsa Shad will be taken to distinguish the actual number of species present in the Indus River of Pakistan..