Search

The length-weight relationships ( LWRs) were studied for 814 individuals covering eight families and 12 species of fish, e.g., Botia dario, Botia lohachata, Channa orientalis, Esomus danricus, Heteropneustes fossilis, Macrognathus pancalus, Nandus nandus, Ompok pabda, Pethia phutunio, Pethia ticto, Trichogaster fasciata and Trichogaster lalius captured from the Gajner beel floodplain, northwestern ( NW) Bangladesh. Samples were collected occasionally from catches of fishermen from November 2014 to October 2015 using different types of traditional fishing gear, including gill net (mesh size ranges from 1.0 to 3.0 cm), cast net (mesh size ranges from 1.0 to 2.0 cm), square lift net (mesh size ~1.0 cm) and conical and box trap. The total length ( TL) and body weight ( BW) were measured for each individual. The allometric co-efficient b values ranged between 2.64 ( B. lohachata) to 3.27 ( N. nandus) and were highly significant, with p < .001 for all species. Additionally, for the first time, the study provides LWR information for B. dario, B. lohachata, E. danricus, O. pabda, T. lalius and P. phutunio, beneficial for fishery biologists and to update the online database (FishBase). The study also recorded a maximum length for P. phutunio. The present observations are significant for the sustainable management and conservation of these fishes in the Gajner beel floodplain, NW Bangladesh and the surrounding ecosystems. [ABSTRACT FROM AUTHOR]

This study focused on the length-weight and length-length relationships of five Mystus species from Bangladesh. A sum of 398 individuals ( Mystus bleekeri = 47, Mystus cavasius = 171, Mystus gulio = 59, Mystus tengra = 65, and Mystus vittatus = 56) was collected from the Ganges and Rupsha rivers, Bangladesh. Fishes were caught by gill net (mesh sizes: 2.0-4.0 cm) and cast net (mesh sizes: 1.5-3.0 cm) from July 2014 to June 2015. Total length ( TL), fork length ( FL) and standard length ( SL) were measured to 0.1 cm, while whole body weight ( W) was taken to the nearest 0.1 g for each individual. The TL ranged from 6.0-13.5 cm for M. bleekeri, 5.0-15.0 cm for M. cavasius, 7.4-17.2 cm for M. gulio, 4.6-11.6 cm for M. tengra and 5.5-12.3 cm for M. vittatus. The W varied from 3.0-18.2 g for M. bleekeri, 1.3-30.4 g for M. cavasius, 6.1-62.2 g for M. gulio, 1.7-15.1 g for M. tengra and 2.7-19.2 g for M. vittatus. All LWRs were highly significant ( p < .001), with all r 2 values ≥.950. The LLRs were also highly significant ( p < .001), with all r 2 ≥.980. This study provides information on LWRs and LLRs for M. gulio and M. tengra for the first time. The results of this study can be very effective for stock assessment of Mystus species in the Ganges and Rupsha rivers as well as in the surrounding ecosystems. [ABSTRACT FROM AUTHOR]