Indian J. Fish., 57(2) : 73-76, 2010 73

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Length-weight relationship and morphometric characteristics of Schizothorax spp. in the River Lidder of Kashmir

F. A. BHAT, A. R. YOUSUF*, M. H. BALKHI, M. D. MAHDI* AND F. A. SHAH Faculty of Fisheries, Sher-e-Kashmir University of Agricultural Sciences and Technology, - 190 006 Jammu and Kashmir, India *Centre of Research for Development, University of Kashmir, Srinagar - 190 006, Jammu and Kashmir, India e-mail: [email protected]

ABSTRACT A study on the biology of fishes of River Lidder was carried out during 2003 – 2005. Seven species of fishes were collected from the river, out of which, three commercially important species of Schizothorax viz., S. plagiostomus, S. esocinus and S. labiatus, dominated the catch both by number and weight. One hundred and thirty three specimens of S. plagiostomus ranging in total length from 96 mm to 520 mm and in weight from 7 g to 948 g, 70 specimens of S. esocinus ranging in total length from 57 mm to 420 mm and in total weight from 1g to 644 g and 40 specimens of S. labiatus ranging in length from 92 mm to 255 mm and in total weight from 7 to 179 g were taken for the study. The value of “n’ fluctuated between 2.9467 to 3.0997. Length–weight relationship in S. plagiostomus was Log W = -4.9653 + 2.9467 Log L, for S. esocinus, Log W = -5.1635 + 3.0034 Log L and for S. labiatus, Log W = -5.2500 + 3.0997 Log L. S. esocinus showed maximum growth in head length, pre-dorsal length, pre-pectoral length and eye diameter, while S. plagiostomus ranked second in pre-dorsal length. The maximum caudal fin length and pre-anal length was observed in S. plagiostomus. The maximum body and peduncle depth was observed in S. labiatus. Due to low pollution load in the River Lidder, the environmental stress on these species seems to be very low order and this has probably led to the almost ideal growth pattern of the three species. Keywords: Kashmir, Length-weight relationship, Morphometry, River Lidder, Schizothorax,

Kashmir valley, situated between 330 01' – 340 08' N lat. During the last three to four decades, human and 740 47'–740 49' E long. at an average altitude of interference as well as natural disturbances like low 1550 m above msl in the midst of Himalayas, is drained by precipitation, low snow fall and low water level, have the River Jhelum and its various tributaries. The river severely impacted the water quality vis-a-vis the distribution receives a number of perennial streams on both sides. Fishes and abundance of the native fish fauna in many aquatic belonging to genus Schizothorax and other carps are habitats, including the Lidder. A detailed work was carried common in rivers and lakes of Kashmir and serve as an on the fish and fishery of River Lidder during 2003 – 2005. important food item of the human population of the region. Data on the morphometric parameters and length-weight The River Lidder, a tributary of the River Jhelum is an relationship of three species of Schizothorax inhabiting the important trout river of Kashmir Himalayas. The river is River Lidder are described here. Generally the weight of a formed by the confluence of the east and west Lidder at fish is expected to increase as a cube of the length under . The former originates from the ideals conditions (Rounsefell and Everhart, 1953; Lagler, (enroute to holly Amarnath cave) while latter originates 1956). Studies on legth-weight relationship of fishes from the Tarsar Lake and Kolhai glaciers (Fig. 1). River constitute an important tool in fishery biology and help to Lidder is famous for the exotic brown trout (Salmo trutta understand whether variations from expected weight for fario) and rainbow trout (Oncorhynchus mykiss), which the known groups are the indicators of fatness, well-being were introduced into the valley at the beginning of the and gonadal development in relation to the environment th 20 century and since then have played an important role (Le Cren, 1951; Bagenal, 1978; Yousuf et al., 2003). in the sport fishery of the valley and are attracting visitors from all over the world. Besides the exotic trouts, Fishes were procured on monthly basis from the river Schizothorax plagiostomus, Schizothorax labiatus, with the help of local fishermen. Freshly caught specimens Schizothorax esocinus, Crossocheilus diplochilus, were used for the measurement of various morphometric Glyptosternon reticulatum and Triplophysa kashmirensis parameters. Length-weight relationship of fishes was are also found in this water body. determined using the formula given by Le Cren (1951) F. A. Bhat et al. 74

(a) (b) Fig. 1. (a) Map of showing River Jhelum system, (b) location of study sites in the Lidder Stream i.e., W= CLn. Identification of the fishes was done following snout length and 6.26 ± 2.08 times the eye diameter and it Day (1887) and Kullander et al. (1999). The growth rate of was having a significant positive relationship (r < 0. 81) different body regions in comparison to total length (TL) with both the parameters. The maximum growth was and head length (HL) was studied by regression analysis, obtained by the regression analysis and value of “b” with using the formula: Y = a + bX, and correlation coefficient respect to total length in the fish was found by the standard (r) between TL, HL with rest of the body parameters was length (0.8538) followed by pre-anal length (0.6115), calculated using SPSS 13 software. pre-pelvic length (0.4290), pre-dorsal length (0.4190), head length (0.177), maximum body depth (0.1683) and Schizothorax genus in the river was represented by pre-pectoral length (0.1648) (Table 1). The length-weight three species i.e., S. plagiostomus, S. esocinus and relationship in the fish was represented by the equation; S. labiatus. S. plagiostomus was the most dominant fish in Log W = -4.9653 + 2.9467 Log L or W=0. 000010831L 2.9467 the river, followed by S. labiatus and S. esocinus. (Fig. 2). A total of 136 specimens of S. plagiostomus were Seventy specimens of S. esocinus having total length collected from the river which ranged in total length from from 57 to 420 mm and weight from 1 to 644 g were 96 to 520 mm and in total weight from 7 to 948 g. The total collected during the period. The total length was 1.20±0.05 length was 1.20±0.02 times the standard length, 7.04±4.82 times the standard length, 4.51±0.29 times the head length, times the head length, 5.92±0.24 times the body depth, 6.28±0.43 times the body depth, 2.37±0.07 times the 2.39±0.17 times the pre-dorsal length, 5.41±0.36 times the pre-dorsal length, 4.68±0.22 times the pre-pectoral length, pre-pectoral length, 2.20±0.20 times the pre-pelvic length 2.25±0.13 times the pre-pelvic length, 1.56±0.09 times the and 1.5±0.14 times the pre-anal length. All these parameters pre-anal length. AIl these parameters recorded significant recorded significant positive relationship (r < 0.87) with positive relationship (r < 0.98) with the total length. Head the total length. Head length was 3.42 ± 0.88 times the length was 3.66±0.43 times the snout length and Table. 1. Correlation coefficient (r) and regression coefficients (a and b) of various morphometric parameters with TL and HL in the three Schizothorax spp. Independent Dependent S. plagiostomus S. esocinus S. labiatus variable variable a b r a b r a b r Total length (TL) Standard length -4.2336 0.8538 0.9997 -12.766 0.908 0.9971 -4.3929 0.8601 0.9999 Head length -2.1446 0.177 0.874 -3.4109 0.2428 0.9962 4.1346 0.167 0.9892 Max. body depth 0.4584 0.1683 0.9846 -2.4396 0.173 0.985 0.7469 0.1712 0.9856 Pre-dorsal L -0.367 0.419 0.9795 -4.2299 0.4453 0.9966 -1.4136 0.4187 0.9965 Pre-pectoral L 4.9095 0.1648 0.9857 -1.151 0.2215 0.9977 4.5973 0.1586 0.9846 Pre-pelvic L 5.9559 0.429 0.9794 -3.1491 0.4594 0.995 -1.8031 0.4415 0.9969 Pre-anal L 13.8970.6115 0.9711 -7.0631 0.6798 0.9922 -3.4357 0.6396 0.9974 Head length (HL) Snout length L 2.7728 0.2402 0.8631 0.5939- 0.2936 0.9366 -2.4686 0.3626 0.8821 Eye diameter L 4.2998 0.0675 0.8189 -0.365 0.1748 0.8076 0.0605 0.2117 0.8157 Length-weight relationship and morphometric characteristics of Schizothorax species 75

the longest head region among the three species (Table 1), being 0.24% of the total length. Because of the longer head in S. esocinus, the pre-dorsal, pre-pectoral, pre-pelvic and pre-anal regions recorded the highest ratio with reference to the total length in this species. However, the ratio between snout length and the eye diameter recorded highest values in S. labiatus. The maximum body depth was observed in S. labiatus followed by S. plagiostomus and the lowest in S. esocinus. The high peduncle depth was found in S. labiatus followed by S. plagiostomus and the lowest in S. esocinus. The variations in various morphometric parameters of the three species were statistically significant and thus can be regarded as different species (Yousuf, 1996; Kullandar et al., 1999; Yousuf et al., 2001). According to Allen (1938) the value of “n” in length- weight relationship remains constant at 3 for an ideal fish living in an ideal condition. However, as a fish passes through several stages, the simple cube law does not hold well throughout its life span and equilibrium constant shows certain variations (Martin, 1949) in the growth pattern of fish. Qadri and Mir (1980) reported the value of “n” as 2.4487 for S. plagiostomus from the peripheral water bodies Fig. 2. Length-weight relationship of Schizothorax sp. in of , while as Bhagat and Sunder (1983) reported River Lidder, Kashmir it to be 2.9288 for the same fish from the Jammu water 5.98±1.57 times the eye diameter. The maximum growth bodies. In case of Lidder, the value of “n” for the fish was with respect to total length in the fish was found by the calculated as 2.9467. Bhagat and Sunder (1984) reported standard length (0.9080) and least by the maximum body the value of “n” as 3.0180 in case of S. esocinus from the depth (0.1730). The length-weight relationship in the fish Dal Lake, while Firdous (1995) reported it to be as 3.1330 was represented by the equation Log W = -5.1635+3.0034 from the ; however, Rather (2002) recorded LogL or W=0. 000006862L 3.0034. the value in the same fish as 2.9270 from the Jhelum. During the present study the value was 3.0334. In S. labiatus the S. labiatus was represented by 40 specimens which value of “n” in the present study was found as 3.0997. ranged in length from 92–255 mm and in weight from Anchar Lake, being eutrophic water body (Pandit and 7 to 179 g. Statistical analysis of the data revealed that the Yousuf, 2002 and Bhat et al., 2001), the deviation of value total length was 1.20±0.01 times the standard length, of “n” in S. esocinus in this water body as compared to 5.19±0.25 times the head length, 5.69±0.24 times the body Lidder is obvious. Among these fishes S. esocinus and depth, 2.44±0.05 times the pre-dorsal length, 5.35±0.30 S. labiatus deviated less from the value of “n” as compared times the pre-pectoral length, 2.32±0.05 times the pre-pelvic to S. plagiostomus. length, 1.62±0.03 times the pre-anal length. All the The growth of fish is very important for more specific parameters showed a significant positive relationship fishery management and is influenced by many (r < 0.98) with the total length. Head length was 3.57±0.41 environmental factors like pH, temperature, salinity, times the snout length and 4.71±0.58 times the eye diameter. dissolved oxygen, ammonia and heavy metal concentration. The maximum growth with respect to total length in the Yousuf and Firdous (1992) and Yousuf et al. (2001) fish was found by the standard length (0.8601) and least by observed that environmental factors are responsible for the pre-pectoral length (0.1586). The relationship between the deviation from the ideal state to a