Comparative account on the length-weight and length-length relationships and condition factor of six cyprinid fishes from Dal Lake, Kashmir

Abstract

Fish landings are routinely measured for length and weight to study fish bioecology, which provide important information about biomass, population dynamics and condition of fish. The current study describes the length-weight relationships (LWRs) and length-length relationships (LLRs) of six fish species (Cyprinus carpio, Carassius carassius, Schizothorax niger, S. curvifrons, Crossocheilus diplochilus and Pethia conchonius) based on seasonal fish sampling from the Dal Lake during September 2019 to August 2020. The estimated LWRs and LLRs were highly significant (p < 0.05) with high coefficient of determination r2 and the estimated b values ranged from 2.50 to 3.55. The estimated b values revealed negative allometric growth of fish species except P. conchonius which possesses positive allometric growth. The mean value of condition factor for C. carpio, C. carassius, S. niger, S. curvifrons, C. diplochilus and P. conchonius were 1.43±0.25, 1.55±0.24, 0.86±0.14, 0.80±0.13, 1.21±0.17 and 1.64±0.34 respectively and it varied significantly among these fish species (ANOVA: p < 0.05). The study shows LWRs, LLRs and current condition of some forage fish species viz., C. carassius, C. diplochilus and P. conchonius as well as invasive C. carpio and local Schizothorax species from the Dal Lake, all possessing economic and conservation significance.

Length-Weight, Length-Length Relationships and Condition Factor of <i>Crossocheilus diplochilus</i> (Heckel) from Dal Lake of Kashmir Himalayas

“…A vital bioecological tool, Length-Weight Relationships (LWRs) provide crucial insights about biomass estimation, fish becoming slimmer as its length increases 4,22 . Similar reports of negative allometric growth have been reported by Sidiq et al, 23 Bhat et al, 11 Qazi et al, 21 and Yousuf et al, 24 in C. diplochilus. The association between LLRs was reported to be highly significant, with r 2 value of 0.98 for TL, SL and FL, which conforms with the findings of Qazi et al, 21 and Malhotra and Chauhan 25 .…”

“…As per the criterion set by Fulton 28 , the condition factor of C. diplochilus is reflective of the poor condition of fish within the lake. The condition factor reported during the current study was found to be lesser than the one reported by Bhat et al, 11 and Yousuf et al, 24 while working in Dal and Manasbal Lake respectively. The probable reasons for the same could be the use of a net with a bigger mesh size during both the studies and better habitat conditions of Manasbal Lake.…”

“…The past work on LWRs and condition factor of C. diplochilus from various aquatic habitats is presented in Table 3. The length and weight range reported during the current investigation is not in conformity with the ones reported earlier by Sharma et al 19 , Mushtaq et al, 20 Bhat et al, 11 and Qazi et al, 21 with the former two reporting higher biometrics and the latter two reporting lower biometrics in comparison to current investigation. Such variations in the biometrics are primarily due to the use of different mesh-sized nets, better conditions of a water body and smaller sample size.…”

“…The current study was conducted in the world-famous Dal Lake, located in the capital city of Srinagar in the Union Territory of Jammu and Kashmir. The lake is located within the coordinates of 34º 04' -34º11' N, 74º 48' -74º 53' E and harbours multiple fish species viz., Schizothorax niger, S. curvifrons, Cyprinus carpio, C. diplochilus, Pethia conchonius, Gambusia holbrooki, Carassius carassius, etc 10,11 . The length-weight data of C. diplochilus was recorded for a period of two years, i.e., from October 2021 to September 2023 from five different sampling sites within the lake (Figure 2).…”

Length-weight relationships and condition factors of mono- and mixed-sex Nile tilapia (Oreochromis niloticus) in open water cage culture system

“…In the cage culture system, length-weight relation-ship (LWR) and condition factor analysis are essential in knowing the growth pattern, age structure, recruitment, mortality and overall well-being of cultured fish species (Das et al 2018;Bhat et al 2022). It is essential to study the LWR to compare the intensification of mono-sex and mixed-sex tilapia culture and production in the open water cage aquaculture system.…”