Biometric indices of eleven mangrove fish species from southwest Bangladesh

Abstract

Biometric indices, i.e. i) length-weight relationships (LWRs), ii) form factor (a3.0), iii) length-frequency distributions (LFDs), and iv) condition factors (relative KR and Fulton’s KF) are considered to be very crucial in the assessment of fishery studies as they provide information on fish population growth and coastal habitat well-being. The study of biometric indices of mangrove fish has, however, received little attention. Our research investigates the LFDs, LWRs, a3.0, KR and KF of 395 individuals from nine families (Latidae, Engraulidae, Gobiidae, Mugilidae, Synbranchidae, Schilbeidae, Scatophagidae, Plotosidae, and Terapontidae). The LFDs showed that the lowest total length (TL) was 4.57 cm for Stolephorus tri, and highest TL was 56.20 for Monopterus cuchia. The LWRs showed that the b (allometric coefficient) values ranging from 2.01 (Plotosus canius) to 3.29 (Terapon jarbua), appeared as highly significant (P < 0.001). Moreover, the KR values ranged from 0.80 to 1.36, which indicate a good state of health of the population. Our findings could be useful in updating the FishBase (online database) and tracking mangrove fish species sustainably.

Keywords

• Length-weight relationship
• Growth
• Form factor
• Condition
• FishBase